[libfmt] Add an internal copy of libfmt-11.1.2.

Currently used as a header-only build. Will eventually be changed to
build a DLL for Windows and Mac OS X.

Other changes needed to get the Windows version to build with libfmt:

Add #include <fmt/xchar.h> to some files for full wchar_t support
in libfmt. Otherwise, errors like this appear:

src\amiibo-data\amiiboc.cpp(175,8): error C2665: 'fmt::v11::print': no overloaded function could convert all the argument types
extlib\libfmt\include\fmt\base.h(2925,17): message : could be 'void fmt::v11::print<TCHAR*&>(FILE *,fmt::v11::fstring<TCHAR *&>,TCHAR *&)'
src\amiibo-data\amiiboc.cpp(175,8): message : 'void fmt::v11::print<TCHAR*&>(FILE *,fmt::v11::fstring<TCHAR *&>,TCHAR *&)': cannot convert argument 2 from 'wmain::<lambda_1>::()::FMT_COMPILE_STRING' to 'fmt::v11::fstring<TCHAR *&>'
src\amiibo-data\amiiboc.cpp(175,22): message : No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called
extlib\libfmt\include\fmt\base.h(2908,17): message : or       'void fmt::v11::print<wmain::<lambda_1>::()::FMT_COMPILE_STRING,TCHAR*&>(fmt::v11::fstring<wmain::<lambda_1>::()::FMT_COMPILE_STRING,TCHAR *&>,wmain::<lambda_1>::()::FMT_COMPILE_STRING &&,TCHAR *&)'
src\amiibo-data\amiiboc.cpp(175,8): message : 'void fmt::v11::print<wmain::<lambda_1>::()::FMT_COMPILE_STRING,TCHAR*&>(fmt::v11::fstring<wmain::<lambda_1>::()::FMT_COMPILE_STRING,TCHAR *&>,wmain::<lambda_1>::()::FMT_COMPILE_STRING &&,TCHAR *&)': cannot convert argument 1 from 'FILE *' to 'fmt::v11::fstring<wmain::<lambda_1>::()::FMT_COMPILE_STRING,TCHAR *&>'
src\amiibo-data\amiiboc.cpp(175,14): message : No constructor could take the source type, or constructor overload resolution was ambiguous
src\amiibo-data\amiiboc.cpp(175,8): message : while trying to match the argument list '(FILE *, wmain::<lambda_1>::()::FMT_COMPILE_STRING, TCHAR *)' [build.vc17_64\src\amiibo-data\amiiboc.vcxproj]

Files modified for xchar.h:
- amiibo-data/amiiboc.cpp
- libromdata/stdafx.h (needed by WiiUPackage)
- libromdata/tests/RomHeaderTest.cpp

NOTE: Only included on Windows. xchar.h was added in libfmt-8.0.0,
which was first added (in Ubuntu LTS releases) in Ubuntu 20.04.
It's not needed on Linux, anyway.

New option USE_INTERNAL_FMT to force the use of the internal copy of
libfmt on Linux, for testing purposes. (...and also for Ubuntu 16.04)
- TODO: Maybe use it on 18.04, etc. for improved performance?

CMakeLists.txt

@@ -338,6 +338,9 @@ ENDIF(USE_INTERNAL_XML)
 IF(BUILD_TESTING)
 	SET(EXTLIB_BUILD "${EXTLIB_BUILD}- Google Test\n")
 ENDIF(BUILD_TESTING)
+IF(USE_INTERNAL_FMT)
+	SET(EXTLIB_BUILD "${EXTLIB_BUILD}- libfmt\n")
+ENDIF(USE_INTERNAL_FMT)
 
 IF(BUILD_TRACKER_EXTRACTOR)
 	SET(TRACKER_API_DISPLAY "${TRACKER_INSTALL_API_VERSION}")

cmake/libs/CheckLibfmt.cmake

@@ -1,11 +1,6 @@
 # Check for libfmt.
 # If libfmt isn't found, extlib/libfmt/ will be used instead.
 
-# TODO: Add internal libfmt.
-FIND_PACKAGE(Fmt REQUIRED)
-SET(Fmt_LIBRARY "fmt::fmt")
-
-IF(0)
 IF(NOT USE_INTERNAL_FMT)
 	IF(Fmt_LIBRARY MATCHES "^fmt$" OR Fmt_LIBRARY MATCHES "^fmt")
 		# Internal libfmt was previously in use.
@@ -20,6 +15,7 @@ IF(NOT USE_INTERNAL_FMT)
 	IF(Fmt_FOUND)
 		# Found system libfmt.
 		SET(HAVE_Fmt 1)
+		SET(Fmt_LIBRARY "fmt::fmt")
 	ELSE()
 		# System libfmt was not found.
 		MESSAGE(STATUS "Using the internal copy of libfmt since a system version was not found.")
@@ -33,16 +29,16 @@ IF(USE_INTERNAL_FMT)
 	# Using the internal libfmt library.
 	SET(Fmt_FOUND 1)
 	SET(HAVE_Fmt 1)
-	SET(Fmt_VERSION 11.1.1 CACHE INTERNAL "libfmt version" FORCE)
+	SET(Fmt_VERSION 11.1.2 CACHE INTERNAL "libfmt version" FORCE)
 	# FIXME: When was it changed from LIBRARY to LIBRARIES?
-	IF(WIN32 OR APPLE)
+	IF(0 AND (WIN32 OR APPLE)) # TODO: Use DLLs on Windows and Mac OS X.
 		# Using DLLs on Windows and Mac OS X.
 		SET(USE_INTERNAL_FMT_DLL ON)
-		SET(Fmt_LIBRARY fmt CACHE INTERNAL "libfmt library" FORCE)
+		SET(Fmt_LIBRARY fmt::fmt CACHE INTERNAL "libfmt library" FORCE)
 	ELSE()
 		# Using static linking on other systems.
 		SET(USE_INTERNAL_FMT_DLL OFF)
-		SET(Fmt_LIBRARY fmt CACHE INTERNAL "libfmt library" FORCE)
+		SET(Fmt_LIBRARY fmt::fmt-header-only CACHE INTERNAL "libfmt library" FORCE)
 	ENDIF()
 	SET(Fmt_LIBRARIES ${Fmt_LIBRARY} CACHE INTERNAL "libfmt libraries" FORCE)
 	# FIXME: When was it changed from DIR to DIRS?
@@ -51,4 +47,4 @@ IF(USE_INTERNAL_FMT)
 ELSE(USE_INTERNAL_FMT)
 	SET(USE_INTERNAL_FMT_DLL OFF)
 ENDIF(USE_INTERNAL_FMT)
-ENDIF(0)
+

cmake/options.cmake

@@ -38,7 +38,7 @@ ENDIF()
 
 OPTION(BUILD_CLI "Build the `rpcli` command line program." ON)
 
-# ZLIB, libpng, XML, zstd
+# ZLIB, libpng, XML, zstd, libfmt
 # Internal versions are always used on Windows.
 OPTION(ENABLE_XML "Enable XML parsing for e.g. Windows manifests." ON)
 OPTION(ENABLE_ZSTD "Enable ZSTD decompression. (Required for some unit tests.)" ON)
@@ -52,6 +52,7 @@ IF(WIN32)
 	SET(USE_INTERNAL_ZSTD ${ENABLE_ZSTD})
 	SET(USE_INTERNAL_LZ4 ${ENABLE_LZ4})
 	SET(USE_INTERNAL_LZO ${ENABLE_LZO})
+	SET(USE_INTERNAL_FMT ON)
 ELSE(WIN32)
 	OPTION(USE_INTERNAL_ZLIB "Use the internal copy of zlib." OFF)
 	OPTION(USE_INTERNAL_PNG "Use the internal copy of libpng." OFF)
@@ -59,6 +60,7 @@ ELSE(WIN32)
 	OPTION(USE_INTERNAL_ZSTD "Use the internal copy of zstd." OFF)
 	OPTION(USE_INTERNAL_LZ4 "Use the internal copy of LZ4." OFF)
 	OPTION(USE_INTERNAL_LZO "Use the internal copy of LZO." OFF)
+	OPTION(USE_INTERNAL_FMT "Use the internal copy of libfmt." OFF)
 ENDIF()
 
 # TODO: If APNG export is added, verify that system libpng

extlib/CMakeLists.txt

@@ -413,3 +413,29 @@ ENDIF(NOT HAVE_WCWIDTH)
 # MicroTAR (for libromdata tests)
 ADD_SUBDIRECTORY(microtar)
 SET_EXTLIB_PROPERTIES(microtar)
+
+IF(USE_INTERNAL_FMT)
+	# Use the internal copy of libfmt.
+	# TODO: Build DLLs on Windows and Mac OS X.
+	# For now, a header-only build will be used.
+	SET(SKIP_INSTALL_LIBRARIES ON)
+	SET(SKIP_INSTALL_ALL ON)
+	SET(BUILD_SHARED_LIBS OFF)
+	SET(BUILD_STATIC_LIBS ON)
+
+	SET(FMT_PEDANTIC OFF)
+	SET(FMT_WERROR OFF)
+
+	SET(FMT_DOC OFF)
+	SET(FMT_INSTALL OFF)	# TODO: Enable for DLL builds?
+	SET(FMT_TEST OFF)
+	SET(FMT_CUDA_TEST OFF)
+	SET(FMT_OS ON)
+	SET(FMT_MODULE OFF)
+	SET(FMT_SYSTEM_HEADERS OFF)
+	SET(FMT_UNICODE ON)
+
+	ADD_SUBDIRECTORY(libfmt)
+	SET_EXTLIB_PROPERTIES(fmt)
+	SET_EXTLIB_PROPERTIES(fmt-header-only)
+ENDIF(USE_INTERNAL_FMT)

extlib/libfmt/.clang-format

@@ -0,0 +1,14 @@
+# Run manually to reformat a file:
+# clang-format -i --style=file <file>
+Language: Cpp
+BasedOnStyle: Google
+IndentPPDirectives: AfterHash
+IndentCaseLabels: false
+AlwaysBreakTemplateDeclarations: false
+DerivePointerAlignment: false
+AllowShortCaseLabelsOnASingleLine: true
+AlignConsecutiveShortCaseStatements:
+  Enabled: true
+  AcrossEmptyLines: true
+  AcrossComments: true
+  AlignCaseColons: false

extlib/libfmt/CMakeLists.txt

@@ -0,0 +1,531 @@
+cmake_minimum_required(VERSION 3.8...3.28)
+
+# Fallback for using newer policies on CMake <3.12.
+if (${CMAKE_VERSION} VERSION_LESS 3.12)
+  cmake_policy(VERSION ${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION})
+endif ()
+
+# Determine if fmt is built as a subproject (using add_subdirectory)
+# or if it is the master project.
+if (NOT DEFINED FMT_MASTER_PROJECT)
+  set(FMT_MASTER_PROJECT OFF)
+  if (CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
+    set(FMT_MASTER_PROJECT ON)
+    message(STATUS "CMake version: ${CMAKE_VERSION}")
+  endif ()
+endif ()
+
+# Joins arguments and places the results in ${result_var}.
+function(join result_var)
+  set(result "")
+  foreach (arg ${ARGN})
+    set(result "${result}${arg}")
+  endforeach ()
+  set(${result_var} "${result}" PARENT_SCOPE)
+endfunction()
+
+# DEPRECATED! Should be merged into add_module_library.
+function(enable_module target)
+  if (MSVC)
+    set(BMI ${CMAKE_CURRENT_BINARY_DIR}/${target}.ifc)
+    target_compile_options(${target}
+      PRIVATE /interface /ifcOutput ${BMI}
+      INTERFACE /reference fmt=${BMI})
+    set_target_properties(${target} PROPERTIES ADDITIONAL_CLEAN_FILES ${BMI})
+    set_source_files_properties(${BMI} PROPERTIES GENERATED ON)
+  endif ()
+endfunction()
+
+set(FMT_USE_CMAKE_MODULES FALSE)
+if (CMAKE_VERSION VERSION_GREATER_EQUAL 3.28 AND
+    CMAKE_GENERATOR STREQUAL "Ninja")
+  set(FMT_USE_CMAKE_MODULES TRUE)
+endif ()
+
+# Adds a library compiled with C++20 module support.
+# `enabled` is a CMake variables that specifies if modules are enabled.
+# If modules are disabled `add_module_library` falls back to creating a
+# non-modular library.
+#
+# Usage:
+#   add_module_library(<name> [sources...] FALLBACK [sources...] [IF enabled])
+function(add_module_library name)
+  cmake_parse_arguments(AML "" "IF" "FALLBACK" ${ARGN})
+  set(sources ${AML_UNPARSED_ARGUMENTS})
+
+  add_library(${name})
+  set_target_properties(${name} PROPERTIES LINKER_LANGUAGE CXX)
+
+  if (NOT ${${AML_IF}})
+    # Create a non-modular library.
+    target_sources(${name} PRIVATE ${AML_FALLBACK})
+    set_target_properties(${name} PROPERTIES CXX_SCAN_FOR_MODULES OFF)
+    return()
+  endif ()
+
+  # Modules require C++20.
+  target_compile_features(${name} PUBLIC cxx_std_20)
+  if (CMAKE_COMPILER_IS_GNUCXX)
+    target_compile_options(${name} PUBLIC -fmodules-ts)
+  endif ()
+
+  target_compile_definitions(${name} PRIVATE FMT_MODULE)
+
+  if (FMT_USE_CMAKE_MODULES)
+    target_sources(${name} PUBLIC FILE_SET fmt TYPE CXX_MODULES
+                   FILES ${sources})
+  else()
+    # `std` is affected by CMake options and may be higher than C++20.
+    get_target_property(std ${name} CXX_STANDARD)
+
+    if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+      set(pcms)
+      foreach (src ${sources})
+        get_filename_component(pcm ${src} NAME_WE)
+        set(pcm ${pcm}.pcm)
+
+        # Propagate -fmodule-file=*.pcm to targets that link with this library.
+        target_compile_options(
+          ${name} PUBLIC -fmodule-file=${CMAKE_CURRENT_BINARY_DIR}/${pcm})
+
+        # Use an absolute path to prevent target_link_libraries prepending -l
+        # to it.
+        set(pcms ${pcms} ${CMAKE_CURRENT_BINARY_DIR}/${pcm})
+        add_custom_command(
+          OUTPUT ${pcm}
+          COMMAND ${CMAKE_CXX_COMPILER}
+                  -std=c++${std} -x c++-module --precompile -c
+                  -o ${pcm} ${CMAKE_CURRENT_SOURCE_DIR}/${src}
+                  "-I$<JOIN:$<TARGET_PROPERTY:${name},INCLUDE_DIRECTORIES>,;-I>"
+          # Required by the -I generator expression above.
+          COMMAND_EXPAND_LISTS
+          DEPENDS ${src})
+      endforeach ()
+
+      # Add .pcm files as sources to make sure they are built before the library.
+      set(sources)
+      foreach (pcm ${pcms})
+        get_filename_component(pcm_we ${pcm} NAME_WE)
+        set(obj ${pcm_we}.o)
+        # Use an absolute path to prevent target_link_libraries prepending -l.
+        set(sources ${sources} ${pcm} ${CMAKE_CURRENT_BINARY_DIR}/${obj})
+        add_custom_command(
+          OUTPUT ${obj}
+          COMMAND ${CMAKE_CXX_COMPILER} $<TARGET_PROPERTY:${name},COMPILE_OPTIONS>
+                  -c -o ${obj} ${pcm}
+          DEPENDS ${pcm})
+      endforeach ()
+    endif ()
+    target_sources(${name} PRIVATE ${sources})
+  endif()
+endfunction()
+
+include(CMakeParseArguments)
+
+# Sets a cache variable with a docstring joined from multiple arguments:
+#   set(<variable> <value>... CACHE <type> <docstring>...)
+# This allows splitting a long docstring for readability.
+function(set_verbose)
+  # cmake_parse_arguments is broken in CMake 3.4 (cannot parse CACHE) so use
+  # list instead.
+  list(GET ARGN 0 var)
+  list(REMOVE_AT ARGN 0)
+  list(GET ARGN 0 val)
+  list(REMOVE_AT ARGN 0)
+  list(REMOVE_AT ARGN 0)
+  list(GET ARGN 0 type)
+  list(REMOVE_AT ARGN 0)
+  join(doc ${ARGN})
+  set(${var} ${val} CACHE ${type} ${doc})
+endfunction()
+
+# Set the default CMAKE_BUILD_TYPE to Release.
+# This should be done before the project command since the latter can set
+# CMAKE_BUILD_TYPE itself (it does so for nmake).
+if (FMT_MASTER_PROJECT AND NOT CMAKE_BUILD_TYPE)
+  set_verbose(CMAKE_BUILD_TYPE Release CACHE STRING
+              "Choose the type of build, options are: None(CMAKE_CXX_FLAGS or "
+              "CMAKE_C_FLAGS used) Debug Release RelWithDebInfo MinSizeRel.")
+endif ()
+
+project(FMT CXX)
+include(GNUInstallDirs)
+set_verbose(FMT_INC_DIR ${CMAKE_INSTALL_INCLUDEDIR} CACHE STRING
+            "Installation directory for include files, a relative path that "
+            "will be joined with ${CMAKE_INSTALL_PREFIX} or an absolute path.")
+
+option(FMT_PEDANTIC "Enable extra warnings and expensive tests." OFF)
+option(FMT_WERROR "Halt the compilation with an error on compiler warnings."
+       OFF)
+
+# Options that control generation of various targets.
+option(FMT_DOC "Generate the doc target." ${FMT_MASTER_PROJECT})
+option(FMT_INSTALL "Generate the install target." ON)
+option(FMT_TEST "Generate the test target." ${FMT_MASTER_PROJECT})
+option(FMT_FUZZ "Generate the fuzz target." OFF)
+option(FMT_CUDA_TEST "Generate the cuda-test target." OFF)
+option(FMT_OS "Include OS-specific APIs." ON)
+option(FMT_MODULE "Build a module instead of a traditional library." OFF)
+option(FMT_SYSTEM_HEADERS "Expose headers with marking them as system." OFF)
+option(FMT_UNICODE "Enable Unicode support." ON)
+
+if (FMT_TEST AND FMT_MODULE)
+  # The tests require {fmt} to be compiled as traditional library
+  message(STATUS "Testing is incompatible with build mode 'module'.")
+endif ()
+set(FMT_SYSTEM_HEADERS_ATTRIBUTE "")
+if (FMT_SYSTEM_HEADERS)
+  set(FMT_SYSTEM_HEADERS_ATTRIBUTE SYSTEM)
+endif ()
+if (CMAKE_SYSTEM_NAME STREQUAL "MSDOS")
+  set(FMT_TEST OFF)
+  message(STATUS "MSDOS is incompatible with gtest")
+endif ()
+
+# Get version from base.h
+file(READ include/fmt/base.h base_h)
+if (NOT base_h MATCHES "FMT_VERSION ([0-9]+)([0-9][0-9])([0-9][0-9])")
+  message(FATAL_ERROR "Cannot get FMT_VERSION from base.h.")
+endif ()
+# Use math to skip leading zeros if any.
+math(EXPR CPACK_PACKAGE_VERSION_MAJOR ${CMAKE_MATCH_1})
+math(EXPR CPACK_PACKAGE_VERSION_MINOR ${CMAKE_MATCH_2})
+math(EXPR CPACK_PACKAGE_VERSION_PATCH ${CMAKE_MATCH_3})
+join(FMT_VERSION ${CPACK_PACKAGE_VERSION_MAJOR}.${CPACK_PACKAGE_VERSION_MINOR}.
+                 ${CPACK_PACKAGE_VERSION_PATCH})
+message(STATUS "{fmt} version: ${FMT_VERSION}")
+
+message(STATUS "Build type: ${CMAKE_BUILD_TYPE}")
+
+if (NOT CMAKE_RUNTIME_OUTPUT_DIRECTORY)
+  set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/bin)
+endif ()
+
+set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH}
+  "${CMAKE_CURRENT_SOURCE_DIR}/support/cmake")
+
+include(CheckCXXCompilerFlag)
+include(JoinPaths)
+
+if (FMT_MASTER_PROJECT AND NOT DEFINED CMAKE_CXX_VISIBILITY_PRESET)
+  set_verbose(CMAKE_CXX_VISIBILITY_PRESET hidden CACHE STRING
+              "Preset for the export of private symbols")
+  set_property(CACHE CMAKE_CXX_VISIBILITY_PRESET PROPERTY STRINGS
+               hidden default)
+endif ()
+
+if (FMT_MASTER_PROJECT AND NOT DEFINED CMAKE_VISIBILITY_INLINES_HIDDEN)
+  set_verbose(CMAKE_VISIBILITY_INLINES_HIDDEN ON CACHE BOOL
+              "Whether to add a compile flag to hide symbols of inline functions")
+endif ()
+
+if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
+  set(PEDANTIC_COMPILE_FLAGS -pedantic-errors -Wall -Wextra -pedantic
+      -Wold-style-cast -Wundef
+      -Wredundant-decls -Wwrite-strings -Wpointer-arith
+      -Wcast-qual -Wformat=2 -Wmissing-include-dirs
+      -Wcast-align
+      -Wctor-dtor-privacy -Wdisabled-optimization
+      -Winvalid-pch -Woverloaded-virtual
+      -Wconversion -Wundef
+      -Wno-ctor-dtor-privacy -Wno-format-nonliteral)
+  if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.6)
+      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS}
+         -Wno-dangling-else -Wno-unused-local-typedefs)
+  endif ()
+  if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5.0)
+      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wdouble-promotion
+          -Wtrampolines -Wzero-as-null-pointer-constant -Wuseless-cast
+          -Wvector-operation-performance -Wsized-deallocation -Wshadow)
+  endif ()
+  if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 6.0)
+      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wshift-overflow=2
+          -Wduplicated-cond)
+      # Workaround for GCC regression
+      # [12/13/14/15 regression] New (since gcc 12) false positive null-dereference in vector.resize
+      # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108860
+      if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 12.0)
+        set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wnull-dereference)
+      endif ()
+  endif ()
+  set(WERROR_FLAG -Werror)
+endif ()
+
+if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+  set(PEDANTIC_COMPILE_FLAGS -Wall -Wextra -pedantic -Wconversion -Wundef
+      -Wdeprecated -Wweak-vtables -Wshadow
+      -Wno-gnu-zero-variadic-macro-arguments)
+  check_cxx_compiler_flag(-Wzero-as-null-pointer-constant HAS_NULLPTR_WARNING)
+  if (HAS_NULLPTR_WARNING)
+    set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS}
+        -Wzero-as-null-pointer-constant)
+  endif ()
+  set(WERROR_FLAG -Werror)
+endif ()
+
+if (MSVC)
+  set(PEDANTIC_COMPILE_FLAGS /W3)
+  set(WERROR_FLAG /WX)
+endif ()
+
+if (FMT_MASTER_PROJECT AND CMAKE_GENERATOR MATCHES "Visual Studio")
+  # If Microsoft SDK is installed create script run-msbuild.bat that
+  # calls SetEnv.cmd to set up build environment and runs msbuild.
+  # It is useful when building Visual Studio projects with the SDK
+  # toolchain rather than Visual Studio.
+  include(FindSetEnv)
+  if (WINSDK_SETENV)
+    set(MSBUILD_SETUP "call \"${WINSDK_SETENV}\"")
+  endif ()
+  # Set FrameworkPathOverride to get rid of MSB3644 warnings.
+  join(netfxpath
+       "C:\\Program Files\\Reference Assemblies\\Microsoft\\Framework\\"
+       ".NETFramework\\v4.0")
+  file(WRITE run-msbuild.bat "
+    ${MSBUILD_SETUP}
+    ${CMAKE_MAKE_PROGRAM} -p:FrameworkPathOverride=\"${netfxpath}\" %*")
+endif ()
+
+function(add_headers VAR)
+  set(headers ${${VAR}})
+  foreach (header ${ARGN})
+    set(headers ${headers} include/fmt/${header})
+  endforeach()
+  set(${VAR} ${headers} PARENT_SCOPE)
+endfunction()
+
+# Define the fmt library, its includes and the needed defines.
+add_headers(FMT_HEADERS args.h base.h chrono.h color.h compile.h core.h format.h
+                        format-inl.h os.h ostream.h printf.h ranges.h std.h
+                        xchar.h)
+set(FMT_SOURCES src/format.cc)
+
+add_module_library(fmt src/fmt.cc FALLBACK
+                   ${FMT_SOURCES} ${FMT_HEADERS} README.md ChangeLog.md
+                   IF FMT_MODULE)
+add_library(fmt::fmt ALIAS fmt)
+if (FMT_MODULE)
+  enable_module(fmt)
+elseif (FMT_OS)
+  target_sources(fmt PRIVATE src/os.cc)
+else()
+  target_compile_definitions(fmt PRIVATE FMT_OS=0)
+endif ()
+
+if (FMT_WERROR)
+  target_compile_options(fmt PRIVATE ${WERROR_FLAG})
+endif ()
+if (FMT_PEDANTIC)
+  target_compile_options(fmt PRIVATE ${PEDANTIC_COMPILE_FLAGS})
+endif ()
+
+if (cxx_std_11 IN_LIST CMAKE_CXX_COMPILE_FEATURES)
+  target_compile_features(fmt PUBLIC cxx_std_11)
+else ()
+  message(WARNING "Feature cxx_std_11 is unknown for the CXX compiler")
+endif ()
+
+target_include_directories(fmt ${FMT_SYSTEM_HEADERS_ATTRIBUTE} BEFORE PUBLIC
+  $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
+  $<INSTALL_INTERFACE:${FMT_INC_DIR}>)
+
+set(FMT_DEBUG_POSTFIX d CACHE STRING "Debug library postfix.")
+
+set_target_properties(fmt PROPERTIES
+  VERSION ${FMT_VERSION} SOVERSION ${CPACK_PACKAGE_VERSION_MAJOR}
+  PUBLIC_HEADER "${FMT_HEADERS}"
+  DEBUG_POSTFIX "${FMT_DEBUG_POSTFIX}"
+
+  # Workaround for Visual Studio 2017:
+  # Ensure the .pdb is created with the same name and in the same directory
+  # as the .lib. Newer VS versions already do this by default, but there is no
+  # harm in setting it for those too. Ignored by other generators.
+  COMPILE_PDB_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}"
+  COMPILE_PDB_NAME "fmt"
+  COMPILE_PDB_NAME_DEBUG "fmt${FMT_DEBUG_POSTFIX}")
+
+# Set FMT_LIB_NAME for pkg-config fmt.pc. We cannot use the OUTPUT_NAME target
+# property because it's not set by default.
+set(FMT_LIB_NAME fmt)
+if (CMAKE_BUILD_TYPE STREQUAL "Debug")
+  set(FMT_LIB_NAME ${FMT_LIB_NAME}${FMT_DEBUG_POSTFIX})
+endif ()
+
+if (BUILD_SHARED_LIBS)
+  target_compile_definitions(fmt PRIVATE FMT_LIB_EXPORT INTERFACE FMT_SHARED)
+endif ()
+if (FMT_SAFE_DURATION_CAST)
+  target_compile_definitions(fmt PUBLIC FMT_SAFE_DURATION_CAST)
+endif ()
+
+add_library(fmt-header-only INTERFACE)
+add_library(fmt::fmt-header-only ALIAS fmt-header-only)
+
+if (NOT MSVC)
+  # Unicode is always supported on compilers other than MSVC.
+elseif (FMT_UNICODE)
+  # Unicode support requires compiling with /utf-8.
+  target_compile_options(fmt PUBLIC $<$<AND:$<COMPILE_LANGUAGE:CXX>,$<CXX_COMPILER_ID:MSVC>>:/utf-8>)
+  target_compile_options(fmt-header-only INTERFACE $<$<AND:$<COMPILE_LANGUAGE:CXX>,$<CXX_COMPILER_ID:MSVC>>:/utf-8>)
+else ()
+  target_compile_definitions(fmt PUBLIC FMT_UNICODE=0)
+endif ()
+
+target_compile_definitions(fmt-header-only INTERFACE FMT_HEADER_ONLY=1)
+target_compile_features(fmt-header-only INTERFACE cxx_std_11)
+
+target_include_directories(fmt-header-only
+  ${FMT_SYSTEM_HEADERS_ATTRIBUTE} BEFORE INTERFACE
+  $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
+  $<INSTALL_INTERFACE:${FMT_INC_DIR}>)
+
+# Install targets.
+if (FMT_INSTALL)
+  include(CMakePackageConfigHelpers)
+  set_verbose(FMT_CMAKE_DIR ${CMAKE_INSTALL_LIBDIR}/cmake/fmt CACHE STRING
+              "Installation directory for cmake files, a relative path that "
+              "will be joined with ${CMAKE_INSTALL_PREFIX} or an absolute "
+              "path.")
+  set(version_config ${PROJECT_BINARY_DIR}/fmt-config-version.cmake)
+  set(project_config ${PROJECT_BINARY_DIR}/fmt-config.cmake)
+  set(pkgconfig ${PROJECT_BINARY_DIR}/fmt.pc)
+  set(targets_export_name fmt-targets)
+
+  set_verbose(FMT_LIB_DIR ${CMAKE_INSTALL_LIBDIR} CACHE STRING
+              "Installation directory for libraries, a relative path that "
+              "will be joined to ${CMAKE_INSTALL_PREFIX} or an absolute path.")
+
+  set_verbose(FMT_PKGCONFIG_DIR ${CMAKE_INSTALL_LIBDIR}/pkgconfig CACHE STRING
+              "Installation directory for pkgconfig (.pc) files, a relative "
+              "path that will be joined with ${CMAKE_INSTALL_PREFIX} or an "
+              "absolute path.")
+
+  # Generate the version, config and target files into the build directory.
+  write_basic_package_version_file(
+    ${version_config}
+    VERSION ${FMT_VERSION}
+    COMPATIBILITY AnyNewerVersion)
+
+  join_paths(libdir_for_pc_file "\${exec_prefix}" "${FMT_LIB_DIR}")
+  join_paths(includedir_for_pc_file "\${prefix}" "${FMT_INC_DIR}")
+
+  configure_file(
+    "${PROJECT_SOURCE_DIR}/support/cmake/fmt.pc.in"
+    "${pkgconfig}"
+    @ONLY)
+  configure_package_config_file(
+    ${PROJECT_SOURCE_DIR}/support/cmake/fmt-config.cmake.in
+    ${project_config}
+    INSTALL_DESTINATION ${FMT_CMAKE_DIR})
+
+  set(INSTALL_TARGETS fmt fmt-header-only)
+
+  set(INSTALL_FILE_SET)
+  if (FMT_USE_CMAKE_MODULES)
+    set(INSTALL_FILE_SET FILE_SET fmt DESTINATION "${FMT_INC_DIR}/fmt")
+  endif()
+
+  # Install the library and headers.
+  install(TARGETS ${INSTALL_TARGETS}
+          COMPONENT fmt-core
+          EXPORT ${targets_export_name}
+          LIBRARY DESTINATION ${FMT_LIB_DIR}
+          ARCHIVE DESTINATION ${FMT_LIB_DIR}
+          PUBLIC_HEADER DESTINATION "${FMT_INC_DIR}/fmt"
+          RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
+          ${INSTALL_FILE_SET})
+
+  # Use a namespace because CMake provides better diagnostics for namespaced
+  # imported targets.
+  export(TARGETS ${INSTALL_TARGETS} NAMESPACE fmt::
+         FILE ${PROJECT_BINARY_DIR}/${targets_export_name}.cmake)
+
+  # Install version, config and target files.
+  install(FILES ${project_config} ${version_config}
+          DESTINATION ${FMT_CMAKE_DIR}
+          COMPONENT fmt-core)
+  install(EXPORT ${targets_export_name} DESTINATION ${FMT_CMAKE_DIR}
+          NAMESPACE fmt::
+          COMPONENT fmt-core)
+
+  install(FILES "${pkgconfig}" DESTINATION "${FMT_PKGCONFIG_DIR}"
+          COMPONENT fmt-core)
+endif ()
+
+function(add_doc_target)
+  find_program(DOXYGEN doxygen
+    PATHS "$ENV{ProgramFiles}/doxygen/bin"
+          "$ENV{ProgramFiles\(x86\)}/doxygen/bin")
+  if (NOT DOXYGEN)
+    message(STATUS "Target 'doc' disabled because doxygen not found")
+    return ()
+  endif ()
+
+  find_program(MKDOCS mkdocs)
+  if (NOT MKDOCS)
+    message(STATUS "Target 'doc' disabled because mkdocs not found")
+    return ()
+  endif ()
+
+  set(sources )
+  foreach (source api.md index.md syntax.md get-started.md fmt.css fmt.js)
+    set(sources ${sources} doc/${source})
+  endforeach()
+
+  add_custom_target(
+    doc
+    COMMAND
+      ${CMAKE_COMMAND}
+        -E env PYTHONPATH=${CMAKE_CURRENT_SOURCE_DIR}/support/python
+        ${MKDOCS} build -f ${CMAKE_CURRENT_SOURCE_DIR}/support/mkdocs.yml
+        # MkDocs requires the site dir to be outside of the doc dir.
+                        --site-dir ${CMAKE_CURRENT_BINARY_DIR}/doc-html
+                        --no-directory-urls
+    SOURCES ${sources})
+
+  include(GNUInstallDirs)
+  install(DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/doc-html/
+          DESTINATION ${CMAKE_INSTALL_DATAROOTDIR}/doc/fmt
+          COMPONENT fmt-doc OPTIONAL)
+endfunction()
+
+if (FMT_DOC)
+  add_doc_target()
+endif ()
+
+if (FMT_TEST)
+  enable_testing()
+  add_subdirectory(test)
+endif ()
+
+# Control fuzzing independent of the unit tests.
+if (FMT_FUZZ)
+  add_subdirectory(test/fuzzing)
+
+  # The FMT_FUZZ macro is used to prevent resource exhaustion in fuzzing
+  # mode and make fuzzing practically possible. It is similar to
+  # FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION but uses a different name to
+  # avoid interfering with fuzzing of projects that use {fmt}.
+  # See also https://llvm.org/docs/LibFuzzer.html#fuzzer-friendly-build-mode.
+  target_compile_definitions(fmt PUBLIC FMT_FUZZ)
+endif ()
+
+set(gitignore ${PROJECT_SOURCE_DIR}/.gitignore)
+if (FMT_MASTER_PROJECT AND EXISTS ${gitignore})
+  # Get the list of ignored files from .gitignore.
+  file (STRINGS ${gitignore} lines)
+  list(REMOVE_ITEM lines /doc/html)
+  foreach (line ${lines})
+    string(REPLACE "." "[.]" line "${line}")
+    string(REPLACE "*" ".*" line "${line}")
+    set(ignored_files ${ignored_files} "${line}$" "${line}/")
+  endforeach ()
+  set(ignored_files ${ignored_files} /.git /build/doxyxml .vagrant)
+
+  set(CPACK_SOURCE_GENERATOR ZIP)
+  set(CPACK_SOURCE_IGNORE_FILES ${ignored_files})
+  set(CPACK_SOURCE_PACKAGE_FILE_NAME fmt-${FMT_VERSION})
+  set(CPACK_PACKAGE_NAME fmt)
+  set(CPACK_RESOURCE_FILE_README ${PROJECT_SOURCE_DIR}/README.md)
+  include(CPack)
+endif ()

extlib/libfmt/CONTRIBUTING.md

@@ -0,0 +1,20 @@
+Contributing to {fmt}
+=====================
+
+By submitting a pull request or a patch, you represent that you have the right
+to license your contribution to the {fmt} project owners and the community,
+agree that your contributions are licensed under the {fmt} license, and agree
+to future changes to the licensing.
+
+All C++ code must adhere to [Google C++ Style Guide](
+https://google.github.io/styleguide/cppguide.html) with the following
+exceptions:
+
+* Exceptions are permitted
+* snake_case should be used instead of UpperCamelCase for function and type
+  names
+
+All documentation must adhere to the [Google Developer Documentation Style
+Guide](https://developers.google.com/style).
+
+Thanks for contributing!

extlib/libfmt/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2012 - present, Victor Zverovich and {fmt} contributors
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+--- Optional exception to the license ---
+
+As an exception, if, as a result of your compiling your source code, portions
+of this Software are embedded into a machine-executable object form of such
+source code, you may redistribute such embedded portions in such object form
+without including the above copyright and permission notices.

extlib/libfmt/README.md

@@ -0,0 +1,485 @@
+<img src="https://user-images.githubusercontent.com/576385/156254208-f5b743a9-88cf-439d-b0c0-923d53e8d551.png" alt="{fmt}" width="25%"/>
+
+[![image](https://github.com/fmtlib/fmt/workflows/linux/badge.svg)](https://github.com/fmtlib/fmt/actions?query=workflow%3Alinux)
+[![image](https://github.com/fmtlib/fmt/workflows/macos/badge.svg)](https://github.com/fmtlib/fmt/actions?query=workflow%3Amacos)
+[![image](https://github.com/fmtlib/fmt/workflows/windows/badge.svg)](https://github.com/fmtlib/fmt/actions?query=workflow%3Awindows)
+[![fmt is continuously fuzzed at oss-fuzz](https://oss-fuzz-build-logs.storage.googleapis.com/badges/fmt.svg)](https://bugs.chromium.org/p/oss-fuzz/issues/list?\%0Acolspec=ID%20Type%20Component%20Status%20Proj%20Reported%20Owner%20\%0ASummary&q=proj%3Dfmt&can=1)
+[![Ask questions at StackOverflow with the tag fmt](https://img.shields.io/badge/stackoverflow-fmt-blue.svg)](https://stackoverflow.com/questions/tagged/fmt)
+[![image](https://api.securityscorecards.dev/projects/github.com/fmtlib/fmt/badge)](https://securityscorecards.dev/viewer/?uri=github.com/fmtlib/fmt)
+
+**{fmt}** is an open-source formatting library providing a fast and safe
+alternative to C stdio and C++ iostreams.
+
+If you like this project, please consider donating to one of the funds
+that help victims of the war in Ukraine: <https://www.stopputin.net/>.
+
+[Documentation](https://fmt.dev)
+
+[Cheat Sheets](https://hackingcpp.com/cpp/libs/fmt.html)
+
+Q&A: ask questions on [StackOverflow with the tag
+fmt](https://stackoverflow.com/questions/tagged/fmt).
+
+Try {fmt} in [Compiler Explorer](https://godbolt.org/z/8Mx1EW73v).
+
+# Features
+
+- Simple [format API](https://fmt.dev/latest/api/) with positional
+  arguments for localization
+- Implementation of [C++20
+  std::format](https://en.cppreference.com/w/cpp/utility/format) and
+  [C++23 std::print](https://en.cppreference.com/w/cpp/io/print)
+- [Format string syntax](https://fmt.dev/latest/syntax/) similar
+  to Python\'s
+  [format](https://docs.python.org/3/library/stdtypes.html#str.format)
+- Fast IEEE 754 floating-point formatter with correct rounding,
+  shortness and round-trip guarantees using the
+  [Dragonbox](https://github.com/jk-jeon/dragonbox) algorithm
+- Portable Unicode support
+- Safe [printf
+  implementation](https://fmt.dev/latest/api/#printf-formatting)
+  including the POSIX extension for positional arguments
+- Extensibility: [support for user-defined
+  types](https://fmt.dev/latest/api/#formatting-user-defined-types)
+- High performance: faster than common standard library
+  implementations of `(s)printf`, iostreams, `to_string` and
+  `to_chars`, see [Speed tests](#speed-tests) and [Converting a
+  hundred million integers to strings per
+  second](http://www.zverovich.net/2020/06/13/fast-int-to-string-revisited.html)
+- Small code size both in terms of source code with the minimum
+  configuration consisting of just three files, `core.h`, `format.h`
+  and `format-inl.h`, and compiled code; see [Compile time and code
+  bloat](#compile-time-and-code-bloat)
+- Reliability: the library has an extensive set of
+  [tests](https://github.com/fmtlib/fmt/tree/master/test) and is
+  [continuously fuzzed](https://bugs.chromium.org/p/oss-fuzz/issues/list?colspec=ID%20Type%20Component%20Status%20Proj%20Reported%20Owner%20Summary&q=proj%3Dfmt&can=1)
+- Safety: the library is fully type-safe, errors in format strings can
+  be reported at compile time, automatic memory management prevents
+  buffer overflow errors
+- Ease of use: small self-contained code base, no external
+  dependencies, permissive MIT
+  [license](https://github.com/fmtlib/fmt/blob/master/LICENSE)
+- [Portability](https://fmt.dev/latest/#portability) with
+  consistent output across platforms and support for older compilers
+- Clean warning-free codebase even on high warning levels such as
+  `-Wall -Wextra -pedantic`
+- Locale independence by default
+- Optional header-only configuration enabled with the
+  `FMT_HEADER_ONLY` macro
+
+See the [documentation](https://fmt.dev) for more details.
+
+# Examples
+
+**Print to stdout** ([run](https://godbolt.org/z/Tevcjh))
+
+``` c++
+#include <fmt/core.h>
+
+int main() {
+  fmt::print("Hello, world!\n");
+}
+```
+
+**Format a string** ([run](https://godbolt.org/z/oK8h33))
+
+``` c++
+std::string s = fmt::format("The answer is {}.", 42);
+// s == "The answer is 42."
+```
+
+**Format a string using positional arguments**
+([run](https://godbolt.org/z/Yn7Txe))
+
+``` c++
+std::string s = fmt::format("I'd rather be {1} than {0}.", "right", "happy");
+// s == "I'd rather be happy than right."
+```
+
+**Print dates and times** ([run](https://godbolt.org/z/c31ExdY3W))
+
+``` c++
+#include <fmt/chrono.h>
+
+int main() {
+  auto now = std::chrono::system_clock::now();
+  fmt::print("Date and time: {}\n", now);
+  fmt::print("Time: {:%H:%M}\n", now);
+}
+```
+
+Output:
+
+    Date and time: 2023-12-26 19:10:31.557195597
+    Time: 19:10
+
+**Print a container** ([run](https://godbolt.org/z/MxM1YqjE7))
+
+``` c++
+#include <vector>
+#include <fmt/ranges.h>
+
+int main() {
+  std::vector<int> v = {1, 2, 3};
+  fmt::print("{}\n", v);
+}
+```
+
+Output:
+
+    [1, 2, 3]
+
+**Check a format string at compile time**
+
+``` c++
+std::string s = fmt::format("{:d}", "I am not a number");
+```
+
+This gives a compile-time error in C++20 because `d` is an invalid
+format specifier for a string.
+
+**Write a file from a single thread**
+
+``` c++
+#include <fmt/os.h>
+
+int main() {
+  auto out = fmt::output_file("guide.txt");
+  out.print("Don't {}", "Panic");
+}
+```
+
+This can be [5 to 9 times faster than
+fprintf](http://www.zverovich.net/2020/08/04/optimal-file-buffer-size.html).
+
+**Print with colors and text styles**
+
+``` c++
+#include <fmt/color.h>
+
+int main() {
+  fmt::print(fg(fmt::color::crimson) | fmt::emphasis::bold,
+             "Hello, {}!\n", "world");
+  fmt::print(fg(fmt::color::floral_white) | bg(fmt::color::slate_gray) |
+             fmt::emphasis::underline, "Olá, {}!\n", "Mundo");
+  fmt::print(fg(fmt::color::steel_blue) | fmt::emphasis::italic,
+             "你好{}！\n", "世界");
+}
+```
+
+Output on a modern terminal with Unicode support:
+
+![image](https://github.com/fmtlib/fmt/assets/%0A576385/2a93c904-d6fa-4aa6-b453-2618e1c327d7)
+
+# Benchmarks
+
+## Speed tests
+
+| Library           | Method        | Run Time, s |
+|-------------------|---------------|-------------|
+| libc              | printf        |   0.91      |
+| libc++            | std::ostream  |   2.49      |
+| {fmt} 9.1         | fmt::print    |   0.74      |
+| Boost Format 1.80 | boost::format |   6.26      |
+| Folly Format      | folly::format |   1.87      |
+
+{fmt} is the fastest of the benchmarked methods, \~20% faster than
+`printf`.
+
+The above results were generated by building `tinyformat_test.cpp` on
+macOS 12.6.1 with `clang++ -O3 -DNDEBUG -DSPEED_TEST -DHAVE_FORMAT`, and
+taking the best of three runs. In the test, the format string
+`"%0.10f:%04d:%+g:%s:%p:%c:%%\n"` or equivalent is filled 2,000,000
+times with output sent to `/dev/null`; for further details refer to the
+[source](https://github.com/fmtlib/format-benchmark/blob/master/src/tinyformat-test.cc).
+
+{fmt} is up to 20-30x faster than `std::ostringstream` and `sprintf` on
+IEEE754 `float` and `double` formatting
+([dtoa-benchmark](https://github.com/fmtlib/dtoa-benchmark)) and faster
+than [double-conversion](https://github.com/google/double-conversion)
+and [ryu](https://github.com/ulfjack/ryu):
+
+[![image](https://user-images.githubusercontent.com/576385/95684665-11719600-0ba8-11eb-8e5b-972ff4e49428.png)](https://fmt.dev/unknown_mac64_clang12.0.html)
+
+## Compile time and code bloat
+
+The script [bloat-test.py][test] from [format-benchmark][bench] tests compile
+time and code bloat for nontrivial projects. It generates 100 translation units
+and uses `printf()` or its alternative five times in each to simulate a
+medium-sized project. The resulting executable size and compile time (Apple
+clang version 15.0.0 (clang-1500.1.0.2.5), macOS Sonoma, best of three) is shown
+in the following tables.
+
+[test]: https://github.com/fmtlib/format-benchmark/blob/master/bloat-test.py
+[bench]: https://github.com/fmtlib/format-benchmark
+
+**Optimized build (-O3)**
+
+| Method        | Compile Time, s | Executable size, KiB | Stripped size, KiB |
+|---------------|-----------------|----------------------|--------------------|
+| printf        |             1.6 |                   54 |                 50 |
+| IOStreams     |            25.9 |                   98 |                 84 |
+| fmt 83652df   |             4.8 |                   54 |                 50 |
+| tinyformat    |            29.1 |                  161 |                136 |
+| Boost Format  |            55.0 |                  530 |                317 |
+
+{fmt} is fast to compile and is comparable to `printf` in terms of per-call
+binary size (within a rounding error on this system).
+
+**Non-optimized build**
+
+| Method        | Compile Time, s | Executable size, KiB | Stripped size, KiB |
+|---------------|-----------------|----------------------|--------------------|
+| printf        |             1.4 |                   54 |                 50 |
+| IOStreams     |            23.4 |                   92 |                 68 |
+| {fmt} 83652df |             4.4 |                   89 |                 85 |
+| tinyformat    |            24.5 |                  204 |                161 |
+| Boost Format  |            36.4 |                  831 |                462 |
+
+`libc`, `lib(std)c++`, and `libfmt` are all linked as shared libraries
+to compare formatting function overhead only. Boost Format is a
+header-only library so it doesn\'t provide any linkage options.
+
+## Running the tests
+
+Please refer to [Building the
+library](https://fmt.dev/latest/get-started/#building-from-source) for
+instructions on how to build the library and run the unit tests.
+
+Benchmarks reside in a separate repository,
+[format-benchmarks](https://github.com/fmtlib/format-benchmark), so to
+run the benchmarks you first need to clone this repository and generate
+Makefiles with CMake:
+
+    $ git clone --recursive https://github.com/fmtlib/format-benchmark.git
+    $ cd format-benchmark
+    $ cmake .
+
+Then you can run the speed test:
+
+    $ make speed-test
+
+or the bloat test:
+
+    $ make bloat-test
+
+# Migrating code
+
+[clang-tidy](https://clang.llvm.org/extra/clang-tidy/) v18 provides the
+[modernize-use-std-print](https://clang.llvm.org/extra/clang-tidy/checks/modernize/use-std-print.html)
+check that is capable of converting occurrences of `printf` and
+`fprintf` to `fmt::print` if configured to do so. (By default it
+converts to `std::print`.)
+
+# Notable projects using this library
+
+- [0 A.D.](https://play0ad.com/): a free, open-source, cross-platform
+  real-time strategy game
+- [AMPL/MP](https://github.com/ampl/mp): an open-source library for
+  mathematical programming
+- [Apple's FoundationDB](https://github.com/apple/foundationdb): an open-source,
+  distributed, transactional key-value store
+- [Aseprite](https://github.com/aseprite/aseprite): animated sprite
+  editor & pixel art tool
+- [AvioBook](https://www.aviobook.aero/en): a comprehensive aircraft
+  operations suite
+- [Blizzard Battle.net](https://battle.net/): an online gaming
+  platform
+- [Celestia](https://celestia.space/): real-time 3D visualization of
+  space
+- [Ceph](https://ceph.com/): a scalable distributed storage system
+- [ccache](https://ccache.dev/): a compiler cache
+- [ClickHouse](https://github.com/ClickHouse/ClickHouse): an
+  analytical database management system
+- [ContextVision](https://www.contextvision.com/): medical imaging software
+- [Contour](https://github.com/contour-terminal/contour/): a modern
+  terminal emulator
+- [CUAUV](https://cuauv.org/): Cornell University\'s autonomous
+  underwater vehicle
+- [Drake](https://drake.mit.edu/): a planning, control, and analysis
+  toolbox for nonlinear dynamical systems (MIT)
+- [Envoy](https://github.com/envoyproxy/envoy): C++ L7 proxy and
+  communication bus (Lyft)
+- [FiveM](https://fivem.net/): a modification framework for GTA V
+- [fmtlog](https://github.com/MengRao/fmtlog): a performant
+  fmtlib-style logging library with latency in nanoseconds
+- [Folly](https://github.com/facebook/folly): Facebook open-source
+  library
+- [GemRB](https://gemrb.org/): a portable open-source implementation
+  of Bioware's Infinity Engine
+- [Grand Mountain
+  Adventure](https://store.steampowered.com/app/1247360/Grand_Mountain_Adventure/):
+  a beautiful open-world ski & snowboarding game
+- [HarpyWar/pvpgn](https://github.com/pvpgn/pvpgn-server): Player vs
+  Player Gaming Network with tweaks
+- [KBEngine](https://github.com/kbengine/kbengine): an open-source
+  MMOG server engine
+- [Keypirinha](https://keypirinha.com/): a semantic launcher for
+  Windows
+- [Kodi](https://kodi.tv/) (formerly xbmc): home theater software
+- [Knuth](https://kth.cash/): high-performance Bitcoin full-node
+- [libunicode](https://github.com/contour-terminal/libunicode/): a
+  modern C++17 Unicode library
+- [MariaDB](https://mariadb.org/): relational database management
+  system
+- [Microsoft Verona](https://github.com/microsoft/verona): research
+  programming language for concurrent ownership
+- [MongoDB](https://mongodb.com/): distributed document database
+- [MongoDB Smasher](https://github.com/duckie/mongo_smasher): a small
+  tool to generate randomized datasets
+- [OpenSpace](https://openspaceproject.com/): an open-source
+  astrovisualization framework
+- [PenUltima Online (POL)](https://www.polserver.com/): an MMO server,
+  compatible with most Ultima Online clients
+- [PyTorch](https://github.com/pytorch/pytorch): an open-source
+  machine learning library
+- [quasardb](https://www.quasardb.net/): a distributed,
+  high-performance, associative database
+- [Quill](https://github.com/odygrd/quill): asynchronous low-latency
+  logging library
+- [QKW](https://github.com/ravijanjam/qkw): generalizing aliasing to
+  simplify navigation, and execute complex multi-line terminal
+  command sequences
+- [redis-cerberus](https://github.com/HunanTV/redis-cerberus): a Redis
+  cluster proxy
+- [redpanda](https://vectorized.io/redpanda): a 10x faster Kafka®
+  replacement for mission-critical systems written in C++
+- [rpclib](http://rpclib.net/): a modern C++ msgpack-RPC server and
+  client library
+- [Salesforce Analytics
+  Cloud](https://www.salesforce.com/analytics-cloud/overview/):
+  business intelligence software
+- [Scylla](https://www.scylladb.com/): a Cassandra-compatible NoSQL
+  data store that can handle 1 million transactions per second on a
+  single server
+- [Seastar](http://www.seastar-project.org/): an advanced, open-source
+  C++ framework for high-performance server applications on modern
+  hardware
+- [spdlog](https://github.com/gabime/spdlog): super fast C++ logging
+  library
+- [Stellar](https://www.stellar.org/): financial platform
+- [Touch Surgery](https://www.touchsurgery.com/): surgery simulator
+- [TrinityCore](https://github.com/TrinityCore/TrinityCore):
+  open-source MMORPG framework
+- [🐙 userver framework](https://userver.tech/): open-source
+  asynchronous framework with a rich set of abstractions and database
+  drivers
+- [Windows Terminal](https://github.com/microsoft/terminal): the new
+  Windows terminal
+
+[More\...](https://github.com/search?q=fmtlib&type=Code)
+
+If you are aware of other projects using this library, please let me
+know by [email](mailto:victor.zverovich@gmail.com) or by submitting an
+[issue](https://github.com/fmtlib/fmt/issues).
+
+# Motivation
+
+So why yet another formatting library?
+
+There are plenty of methods for doing this task, from standard ones like
+the printf family of function and iostreams to Boost Format and
+FastFormat libraries. The reason for creating a new library is that
+every existing solution that I found either had serious issues or
+didn\'t provide all the features I needed.
+
+## printf
+
+The good thing about `printf` is that it is pretty fast and readily
+available being a part of the C standard library. The main drawback is
+that it doesn\'t support user-defined types. `printf` also has safety
+issues although they are somewhat mitigated with [\_\_attribute\_\_
+((format (printf,
+\...))](https://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html) in
+GCC. There is a POSIX extension that adds positional arguments required
+for
+[i18n](https://en.wikipedia.org/wiki/Internationalization_and_localization)
+to `printf` but it is not a part of C99 and may not be available on some
+platforms.
+
+## iostreams
+
+The main issue with iostreams is best illustrated with an example:
+
+``` c++
+std::cout << std::setprecision(2) << std::fixed << 1.23456 << "\n";
+```
+
+which is a lot of typing compared to printf:
+
+``` c++
+printf("%.2f\n", 1.23456);
+```
+
+Matthew Wilson, the author of FastFormat, called this \"chevron hell\".
+iostreams don\'t support positional arguments by design.
+
+The good part is that iostreams support user-defined types and are safe
+although error handling is awkward.
+
+## Boost Format
+
+This is a very powerful library that supports both `printf`-like format
+strings and positional arguments. Its main drawback is performance.
+According to various benchmarks, it is much slower than other methods
+considered here. Boost Format also has excessive build times and severe
+code bloat issues (see [Benchmarks](#benchmarks)).
+
+## FastFormat
+
+This is an interesting library that is fast, safe and has positional
+arguments. However, it has significant limitations, citing its author:
+
+> Three features that have no hope of being accommodated within the
+> current design are:
+>
+> - Leading zeros (or any other non-space padding)
+> - Octal/hexadecimal encoding
+> - Runtime width/alignment specification
+
+It is also quite big and has a heavy dependency, on STLSoft, which might be
+too restrictive for use in some projects.
+
+## Boost Spirit.Karma
+
+This is not a formatting library but I decided to include it here for
+completeness. As iostreams, it suffers from the problem of mixing
+verbatim text with arguments. The library is pretty fast, but slower on
+integer formatting than `fmt::format_to` with format string compilation
+on Karma\'s own benchmark, see [Converting a hundred million integers to
+strings per
+second](http://www.zverovich.net/2020/06/13/fast-int-to-string-revisited.html).
+
+# License
+
+{fmt} is distributed under the MIT
+[license](https://github.com/fmtlib/fmt/blob/master/LICENSE).
+
+# Documentation License
+
+The [Format String Syntax](https://fmt.dev/latest/syntax/) section
+in the documentation is based on the one from Python [string module
+documentation](https://docs.python.org/3/library/string.html#module-string).
+For this reason, the documentation is distributed under the Python
+Software Foundation license available in
+[doc/python-license.txt](https://raw.github.com/fmtlib/fmt/master/doc/python-license.txt).
+It only applies if you distribute the documentation of {fmt}.
+
+# Maintainers
+
+The {fmt} library is maintained by Victor Zverovich
+([vitaut](https://github.com/vitaut)) with contributions from many other
+people. See
+[Contributors](https://github.com/fmtlib/fmt/graphs/contributors) and
+[Releases](https://github.com/fmtlib/fmt/releases) for some of the
+names. Let us know if your contribution is not listed or mentioned
+incorrectly and we\'ll make it right.
+
+# Security Policy
+
+To report a security issue, please disclose it at [security
+advisory](https://github.com/fmtlib/fmt/security/advisories/new).
+
+This project is maintained by a team of volunteers on a
+reasonable-effort basis. As such, please give us at least *90* days to
+work on a fix before public exposure.

extlib/libfmt/_MODIFIED_LIBFMT.txt

@@ -0,0 +1,13 @@
+This copy of libfmt 11.1.2 is a modified version of the original.
+
+commit 8303d140a1a11f19b982a9f664bbe59a1ccda3f4
+Update version
+    
+Tag: 11.1.2
+
+The following changes have been made to the original:
+
+- Removed documentation and test suites.
+
+To obtain the original libfmt-11.1.2, visit:
+https://github.com/fmtlib/fmt

extlib/libfmt/doc/api.md

@@ -0,0 +1,673 @@
+# API Reference
+
+The {fmt} library API consists of the following components:
+
+- [`fmt/base.h`](#base-api): the base API providing main formatting functions
+  for `char`/UTF-8 with C++20 compile-time checks and minimal dependencies
+- [`fmt/format.h`](#format-api): `fmt::format` and other formatting functions
+  as well as locale support
+- [`fmt/ranges.h`](#ranges-api): formatting of ranges and tuples
+- [`fmt/chrono.h`](#chrono-api): date and time formatting
+- [`fmt/std.h`](#std-api): formatters for standard library types
+- [`fmt/compile.h`](#compile-api): format string compilation
+- [`fmt/color.h`](#color-api): terminal colors and text styles
+- [`fmt/os.h`](#os-api): system APIs
+- [`fmt/ostream.h`](#ostream-api): `std::ostream` support
+- [`fmt/args.h`](#args-api): dynamic argument lists
+- [`fmt/printf.h`](#printf-api): safe `printf`
+- [`fmt/xchar.h`](#xchar-api): optional `wchar_t` support
+
+All functions and types provided by the library reside in namespace `fmt`
+and macros have prefix `FMT_`.
+
+## Base API
+
+`fmt/base.h` defines the base API which provides main formatting functions
+for `char`/UTF-8 with C++20 compile-time checks. It has minimal include
+dependencies for better compile times. This header is only beneficial when
+using {fmt} as a library (the default) and not in the header-only mode.
+It also provides `formatter` specializations for the following types:
+
+- `int`, `long long`,
+- `unsigned`, `unsigned long long`
+- `float`, `double`, `long double`
+- `bool`
+- `char`
+- `const char*`, [`fmt::string_view`](#basic_string_view)
+- `const void*`
+
+The following functions use [format string syntax](syntax.md) similar to that
+of [str.format](https://docs.python.org/3/library/stdtypes.html#str.format)
+in Python. They take *fmt* and *args* as arguments.
+
+*fmt* is a format string that contains literal text and replacement fields
+surrounded by braces `{}`. The fields are replaced with formatted arguments
+in the resulting string. [`fmt::format_string`](#format_string) is a format
+string which can be implicitly constructed from a string literal or a
+`constexpr` string and is checked at compile time in C++20. To pass a runtime
+format string wrap it in [`fmt::runtime`](#runtime).
+
+*args* is an argument list representing objects to be formatted.
+
+I/O errors are reported as [`std::system_error`](
+https://en.cppreference.com/w/cpp/error/system_error) exceptions unless
+specified otherwise.
+
+::: print(format_string<T...>, T&&...)
+
+::: print(FILE*, format_string<T...>, T&&...)
+
+::: println(format_string<T...>, T&&...)
+
+::: println(FILE*, format_string<T...>, T&&...)
+
+::: format_to(OutputIt&&, format_string<T...>, T&&...)
+
+::: format_to_n(OutputIt, size_t, format_string<T...>, T&&...)
+
+::: format_to_n_result
+
+::: formatted_size(format_string<T...>, T&&...)
+
+<a id="udt"></a>
+### Formatting User-Defined Types
+
+The {fmt} library provides formatters for many standard C++ types.
+See [`fmt/ranges.h`](#ranges-api) for ranges and tuples including standard
+containers such as `std::vector`, [`fmt/chrono.h`](#chrono-api) for date and
+time formatting and [`fmt/std.h`](#std-api) for other standard library types.
+
+There are two ways to make a user-defined type formattable: providing a
+`format_as` function or specializing the `formatter` struct template.
+
+Use `format_as` if you want to make your type formattable as some other
+type with the same format specifiers. The `format_as` function should
+take an object of your type and return an object of a formattable type.
+It should be defined in the same namespace as your type.
+
+Example ([run](https://godbolt.org/z/nvME4arz8)):
+
+    #include <fmt/format.h>
+
+    namespace kevin_namespacy {
+
+    enum class film {
+      house_of_cards, american_beauty, se7en = 7
+    };
+
+    auto format_as(film f) { return fmt::underlying(f); }
+
+    }
+
+    int main() {
+      fmt::print("{}\n", kevin_namespacy::film::se7en); // Output: 7
+    }
+
+Using specialization is more complex but gives you full control over
+parsing and formatting. To use this method specialize the `formatter`
+struct template for your type and implement `parse` and `format`
+methods.
+
+The recommended way of defining a formatter is by reusing an existing
+one via inheritance or composition. This way you can support standard
+format specifiers without implementing them yourself. For example:
+
+```c++
+// color.h:
+#include <fmt/base.h>
+
+enum class color {red, green, blue};
+
+template <> struct fmt::formatter<color>: formatter<string_view> {
+  // parse is inherited from formatter<string_view>.
+
+  auto format(color c, format_context& ctx) const
+    -> format_context::iterator;
+};
+```
+
+```c++
+// color.cc:
+#include "color.h"
+#include <fmt/format.h>
+
+auto fmt::formatter<color>::format(color c, format_context& ctx) const
+    -> format_context::iterator {
+  string_view name = "unknown";
+  switch (c) {
+  case color::red:   name = "red"; break;
+  case color::green: name = "green"; break;
+  case color::blue:  name = "blue"; break;
+  }
+  return formatter<string_view>::format(name, ctx);
+}
+```
+
+Note that `formatter<string_view>::format` is defined in `fmt/format.h`
+so it has to be included in the source file. Since `parse` is inherited
+from `formatter<string_view>` it will recognize all string format
+specifications, for example
+
+```c++
+fmt::format("{:>10}", color::blue)
+```
+
+will return `"      blue"`.
+
+<!-- The experimental `nested_formatter` provides an easy way of applying a
+formatter to one or more subobjects.
+
+For example:
+
+    #include <fmt/format.h>
+
+    struct point {
+      double x, y;
+    };
+
+    template <>
+    struct fmt::formatter<point> : nested_formatter<double> {
+      auto format(point p, format_context& ctx) const {
+        return write_padded(ctx, [=](auto out) {
+          return format_to(out, "({}, {})", this->nested(p.x),
+                           this->nested(p.y));
+        });
+      }
+    };
+
+    int main() {
+      fmt::print("[{:>20.2f}]", point{1, 2});
+    }
+
+prints:
+
+    [          (1.00, 2.00)]
+
+Notice that fill, align and width are applied to the whole object which
+is the recommended behavior while the remaining specifiers apply to
+elements. -->
+
+In general the formatter has the following form:
+
+    template <> struct fmt::formatter<T> {
+      // Parses format specifiers and stores them in the formatter.
+      //
+      // [ctx.begin(), ctx.end()) is a, possibly empty, character range that
+      // contains a part of the format string starting from the format
+      // specifications to be parsed, e.g. in
+      //
+      //   fmt::format("{:f} continued", ...);
+      //
+      // the range will contain "f} continued". The formatter should parse
+      // specifiers until '}' or the end of the range. In this example the
+      // formatter should parse the 'f' specifier and return an iterator
+      // pointing to '}'.
+      constexpr auto parse(format_parse_context& ctx)
+        -> format_parse_context::iterator;
+
+      // Formats value using the parsed format specification stored in this
+      // formatter and writes the output to ctx.out().
+      auto format(const T& value, format_context& ctx) const
+        -> format_context::iterator;
+    };
+
+It is recommended to at least support fill, align and width that apply
+to the whole object and have the same semantics as in standard
+formatters.
+
+You can also write a formatter for a hierarchy of classes:
+
+```c++
+// demo.h:
+#include <type_traits>
+#include <fmt/core.h>
+
+struct A {
+  virtual ~A() {}
+  virtual std::string name() const { return "A"; }
+};
+
+struct B : A {
+  virtual std::string name() const { return "B"; }
+};
+
+template <typename T>
+struct fmt::formatter<T, std::enable_if_t<std::is_base_of_v<A, T>, char>> :
+    fmt::formatter<std::string> {
+  auto format(const A& a, format_context& ctx) const {
+    return formatter<std::string>::format(a.name(), ctx);
+  }
+};
+```
+
+```c++
+// demo.cc:
+#include "demo.h"
+#include <fmt/format.h>
+
+int main() {
+  B b;
+  A& a = b;
+  fmt::print("{}", a); // Output: B
+}
+```
+
+Providing both a `formatter` specialization and a `format_as` overload is
+disallowed.
+
+::: basic_format_parse_context
+
+::: context
+
+::: format_context
+
+### Compile-Time Checks
+
+Compile-time format string checks are enabled by default on compilers
+that support C++20 `consteval`. On older compilers you can use the
+[FMT_STRING](#legacy-checks) macro defined in `fmt/format.h` instead.
+
+Unused arguments are allowed as in Python's `str.format` and ordinary functions.
+
+See [Type Erasure](#type-erasure) for an example of how to enable compile-time
+checks in your own functions with `fmt::format_string` while avoiding template
+bloat.
+
+::: fstring
+
+::: format_string
+
+::: runtime(string_view)
+
+### Type Erasure
+
+You can create your own formatting function with compile-time checks and
+small binary footprint, for example ([run](https://godbolt.org/z/b9Pbasvzc)):
+
+```c++
+#include <fmt/format.h>
+
+void vlog(const char* file, int line,
+          fmt::string_view fmt, fmt::format_args args) {
+  fmt::print("{}: {}: {}", file, line, fmt::vformat(fmt, args));
+}
+
+template <typename... T>
+void log(const char* file, int line,
+         fmt::format_string<T...> fmt, T&&... args) {
+  vlog(file, line, fmt, fmt::make_format_args(args...));
+}
+
+#define MY_LOG(fmt, ...) log(__FILE__, __LINE__, fmt, __VA_ARGS__)
+
+MY_LOG("invalid squishiness: {}", 42);
+```
+
+Note that `vlog` is not parameterized on argument types which improves
+compile times and reduces binary code size compared to a fully
+parameterized version.
+
+::: make_format_args(T&...)
+
+::: basic_format_args
+
+::: format_args
+
+::: basic_format_arg
+
+### Named Arguments
+
+::: arg(const Char*, const T&)
+
+Named arguments are not supported in compile-time checks at the moment.
+
+### Compatibility
+
+::: basic_string_view
+
+::: string_view
+
+## Format API
+
+`fmt/format.h` defines the full format API providing additional
+formatting functions and locale support.
+
+<a id="format"></a>
+::: format(format_string<T...>, T&&...)
+
+::: vformat(string_view, format_args)
+
+::: operator""_a()
+
+### Utilities
+
+::: ptr(T)
+
+::: underlying(Enum)
+
+::: to_string(const T&)
+
+::: group_digits(T)
+
+::: detail::buffer
+
+::: basic_memory_buffer
+
+### System Errors
+
+{fmt} does not use `errno` to communicate errors to the user, but it may
+call system functions which set `errno`. Users should not make any
+assumptions about the value of `errno` being preserved by library
+functions.
+
+::: system_error
+
+::: format_system_error
+
+### Custom Allocators
+
+The {fmt} library supports custom dynamic memory allocators. A custom
+allocator class can be specified as a template argument to
+[`fmt::basic_memory_buffer`](#basic_memory_buffer):
+
+    using custom_memory_buffer = 
+      fmt::basic_memory_buffer<char, fmt::inline_buffer_size, custom_allocator>;
+
+It is also possible to write a formatting function that uses a custom
+allocator:
+
+    using custom_string =
+      std::basic_string<char, std::char_traits<char>, custom_allocator>;
+
+    auto vformat(custom_allocator alloc, fmt::string_view fmt,
+                 fmt::format_args args) -> custom_string {
+      auto buf = custom_memory_buffer(alloc);
+      fmt::vformat_to(std::back_inserter(buf), fmt, args);
+      return custom_string(buf.data(), buf.size(), alloc);
+    }
+
+    template <typename ...Args>
+    auto format(custom_allocator alloc, fmt::string_view fmt,
+                const Args& ... args) -> custom_string {
+      return vformat(alloc, fmt, fmt::make_format_args(args...));
+    }
+
+The allocator will be used for the output container only. Formatting
+functions normally don't do any allocations for built-in and string
+types except for non-default floating-point formatting that occasionally
+falls back on `sprintf`.
+
+### Locale
+
+All formatting is locale-independent by default. Use the `'L'` format
+specifier to insert the appropriate number separator characters from the
+locale:
+
+    #include <fmt/core.h>
+    #include <locale>
+
+    std::locale::global(std::locale("en_US.UTF-8"));
+    auto s = fmt::format("{:L}", 1000000);  // s == "1,000,000"
+
+`fmt/format.h` provides the following overloads of formatting functions
+that take `std::locale` as a parameter. The locale type is a template
+parameter to avoid the expensive `<locale>` include.
+
+::: format(const Locale&, format_string<T...>, T&&...)
+
+::: format_to(OutputIt, const Locale&, format_string<T...>, T&&...)
+
+::: formatted_size(const Locale&, format_string<T...>, T&&...)
+
+<a id="legacy-checks"></a>
+### Legacy Compile-Time Checks
+
+`FMT_STRING` enables compile-time checks on older compilers. It requires
+C++14 or later and is a no-op in C++11.
+
+::: FMT_STRING
+
+To force the use of legacy compile-time checks, define the preprocessor
+variable `FMT_ENFORCE_COMPILE_STRING`. When set, functions accepting
+`FMT_STRING` will fail to compile with regular strings.
+
+<a id="ranges-api"></a>
+## Range and Tuple Formatting
+
+`fmt/ranges.h` provides formatting support for ranges and tuples:
+
+    #include <fmt/ranges.h>
+
+    fmt::print("{}", std::tuple<char, int>{'a', 42});
+    // Output: ('a', 42)
+
+Using `fmt::join`, you can separate tuple elements with a custom separator:
+
+    #include <fmt/ranges.h>
+
+    auto t = std::tuple<int, char>{1, 'a'};
+    fmt::print("{}", fmt::join(t, ", "));
+    // Output: 1, a
+
+::: join(Range&&, string_view)
+
+::: join(It, Sentinel, string_view)
+
+::: join(std::initializer_list<T>, string_view)
+
+<a id="chrono-api"></a>
+## Date and Time Formatting
+
+`fmt/chrono.h` provides formatters for
+
+- [`std::chrono::duration`](https://en.cppreference.com/w/cpp/chrono/duration)
+- [`std::chrono::time_point`](
+  https://en.cppreference.com/w/cpp/chrono/time_point)
+- [`std::tm`](https://en.cppreference.com/w/cpp/chrono/c/tm)
+
+The format syntax is described in [Chrono Format Specifications](syntax.md#
+chrono-format-specifications).
+
+**Example**:
+
+    #include <fmt/chrono.h>
+
+    int main() {
+      std::time_t t = std::time(nullptr);
+
+      fmt::print("The date is {:%Y-%m-%d}.", fmt::localtime(t));
+      // Output: The date is 2020-11-07.
+      // (with 2020-11-07 replaced by the current date)
+
+      using namespace std::literals::chrono_literals;
+
+      fmt::print("Default format: {} {}\n", 42s, 100ms);
+      // Output: Default format: 42s 100ms
+
+      fmt::print("strftime-like format: {:%H:%M:%S}\n", 3h + 15min + 30s);
+      // Output: strftime-like format: 03:15:30
+    }
+
+::: localtime(std::time_t)
+
+::: gmtime(std::time_t)
+
+<a id="std-api"></a>
+## Standard Library Types Formatting
+
+`fmt/std.h` provides formatters for:
+
+- [`std::atomic`](https://en.cppreference.com/w/cpp/atomic/atomic)
+- [`std::atomic_flag`](https://en.cppreference.com/w/cpp/atomic/atomic_flag)
+- [`std::bitset`](https://en.cppreference.com/w/cpp/utility/bitset)
+- [`std::error_code`](https://en.cppreference.com/w/cpp/error/error_code)
+- [`std::exception`](https://en.cppreference.com/w/cpp/error/exception)
+- [`std::filesystem::path`](https://en.cppreference.com/w/cpp/filesystem/path)
+- [`std::monostate`](
+  https://en.cppreference.com/w/cpp/utility/variant/monostate)
+- [`std::optional`](https://en.cppreference.com/w/cpp/utility/optional)
+- [`std::source_location`](
+  https://en.cppreference.com/w/cpp/utility/source_location)
+- [`std::thread::id`](https://en.cppreference.com/w/cpp/thread/thread/id)
+- [`std::variant`](https://en.cppreference.com/w/cpp/utility/variant/variant)
+
+::: ptr(const std::unique_ptr<T, Deleter>&)
+
+::: ptr(const std::shared_ptr<T>&)
+
+### Variants
+
+A `std::variant` is only formattable if every variant alternative is
+formattable, and requires the `__cpp_lib_variant` [library
+feature](https://en.cppreference.com/w/cpp/feature_test).
+
+**Example**:
+
+    #include <fmt/std.h>
+
+    fmt::print("{}", std::variant<char, float>('x'));
+    // Output: variant('x')
+
+    fmt::print("{}", std::variant<std::monostate, char>());
+    // Output: variant(monostate)
+
+## Bit-Fields and Packed Structs
+
+To format a bit-field or a field of a struct with `__attribute__((packed))`
+applied to it, you need to convert it to the underlying or compatible type via
+a cast or a unary `+` ([godbolt](https://www.godbolt.org/z/3qKKs6T5Y)):
+
+```c++
+struct smol {
+  int bit : 1;
+};
+
+auto s = smol();
+fmt::print("{}", +s.bit);
+```
+
+This is a known limitation of "perfect" forwarding in C++.
+
+<a id="compile-api"></a>
+## Format String Compilation
+
+`fmt/compile.h` provides format string compilation and compile-time
+(`constexpr`) formatting enabled via the `FMT_COMPILE` macro or the `_cf`
+user-defined literal defined in namespace `fmt::literals`. Format strings
+marked with `FMT_COMPILE` or `_cf` are parsed, checked and converted into
+efficient formatting code at compile-time. This supports arguments of built-in
+and string types as well as user-defined types with `format` functions taking
+the format context type as a template parameter in their `formatter`
+specializations. For example:
+
+    template <> struct fmt::formatter<point> {
+      constexpr auto parse(format_parse_context& ctx);
+
+      template <typename FormatContext>
+      auto format(const point& p, FormatContext& ctx) const;
+    };
+
+Format string compilation can generate more binary code compared to the
+default API and is only recommended in places where formatting is a
+performance bottleneck.
+
+::: FMT_COMPILE
+
+::: operator""_cf
+
+<a id="color-api"></a>
+## Terminal Colors and Text Styles
+
+`fmt/color.h` provides support for terminal color and text style output.
+
+::: print(const text_style&, format_string<T...>, T&&...)
+
+::: fg(detail::color_type)
+
+::: bg(detail::color_type)
+
+::: styled(const T&, text_style)
+
+<a id="os-api"></a>
+## System APIs
+
+::: ostream
+
+::: windows_error
+
+<a id="ostream-api"></a>
+## `std::ostream` Support
+
+`fmt/ostream.h` provides `std::ostream` support including formatting of
+user-defined types that have an overloaded insertion operator
+(`operator<<`). In order to make a type formattable via `std::ostream`
+you should provide a `formatter` specialization inherited from
+`ostream_formatter`:
+
+    #include <fmt/ostream.h>
+
+    struct date {
+      int year, month, day;
+
+      friend std::ostream& operator<<(std::ostream& os, const date& d) {
+        return os << d.year << '-' << d.month << '-' << d.day;
+      }
+    };
+
+    template <> struct fmt::formatter<date> : ostream_formatter {};
+
+    std::string s = fmt::format("The date is {}", date{2012, 12, 9});
+    // s == "The date is 2012-12-9"
+
+::: streamed(const T&)
+
+::: print(std::ostream&, format_string<T...>, T&&...)
+
+<a id="args-api"></a>
+## Dynamic Argument Lists
+
+The header `fmt/args.h` provides `dynamic_format_arg_store`, a builder-like API
+that can be used to construct format argument lists dynamically.
+
+::: dynamic_format_arg_store
+
+<a id="printf-api"></a>
+## Safe `printf`
+
+The header `fmt/printf.h` provides `printf`-like formatting
+functionality. The following functions use [printf format string
+syntax](https://pubs.opengroup.org/onlinepubs/009695399/functions/fprintf.html)
+with the POSIX extension for positional arguments. Unlike their standard
+counterparts, the `fmt` functions are type-safe and throw an exception
+if an argument type doesn't match its format specification.
+
+::: printf(string_view, const T&...)
+
+::: fprintf(std::FILE*, const S&, const T&...)
+
+::: sprintf(const S&, const T&...)
+
+<a id="xchar-api"></a>
+## Wide Strings
+
+The optional header `fmt/xchar.h` provides support for `wchar_t` and
+exotic character types.
+
+::: is_char
+
+::: wstring_view
+
+::: wformat_context
+
+::: to_wstring(const T&)
+
+## Compatibility with C++20 `std::format`
+
+{fmt} implements nearly all of the [C++20 formatting
+library](https://en.cppreference.com/w/cpp/utility/format) with the
+following differences:
+
+- Names are defined in the `fmt` namespace instead of `std` to avoid
+  collisions with standard library implementations.
+- Width calculation doesn't use grapheme clusterization. The latter has
+  been implemented in a separate branch but hasn't been integrated yet.

extlib/libfmt/doc/fmt.css

@@ -0,0 +1,61 @@
+:root {
+  --md-primary-fg-color: #0050D0;
+}
+
+.md-grid {
+  max-width: 960px;
+}
+
+@media (min-width: 400px) {
+  .md-tabs {
+    display: block;
+  }
+}
+
+.docblock {
+  border-left: .05rem solid var(--md-primary-fg-color);
+}
+
+.docblock-desc {
+  margin-left: 1em;
+}
+
+pre > code.decl {
+  white-space: pre-wrap;
+}
+
+
+code.decl > div {
+  text-indent: -2ch; /* Negative indent to counteract the indent on the first line */
+  padding-left: 2ch; /* Add padding to the left to create an indent */
+}
+
+.features-container {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 20px;
+  justify-content: center; /* Center the items horizontally */
+}
+
+.feature {
+  flex: 1 1 calc(50% - 20px); /* Two columns with space between */
+  max-width: 600px; /* Set the maximum width for the feature boxes */
+  box-sizing: border-box;
+  padding: 10px;
+  overflow: hidden; /* Hide overflow content */
+  text-overflow: ellipsis; /* Handle text overflow */
+  white-space: normal; /* Allow text wrapping */
+}
+
+.feature h2 {
+  margin-top: 0px;
+  font-weight: bold;
+}
+
+@media (max-width: 768px) {
+  .feature {
+      flex: 1 1 100%; /* Stack columns on smaller screens */
+      max-width: 100%; /* Allow full width on smaller screens */
+      white-space: normal; /* Allow text wrapping on smaller screens */
+  }
+}

extlib/libfmt/doc/fmt.js

@@ -0,0 +1,4 @@
+document$.subscribe(() => {
+  hljs.highlightAll(),
+  { language: 'c++' }
+})

extlib/libfmt/doc/get-started.md

@@ -0,0 +1,222 @@
+# Get Started
+
+Compile and run {fmt} examples online with [Compiler Explorer](
+https://godbolt.org/z/P7h6cd6o3).
+
+{fmt} is compatible with any build system. The next section describes its usage
+with CMake, while the [Build Systems](#build-systems) section covers the rest.
+
+## CMake
+
+{fmt} provides two CMake targets: `fmt::fmt` for the compiled library and
+`fmt::fmt-header-only` for the header-only library. It is recommended to use
+the compiled library for improved build times.
+
+There are three primary ways to use {fmt} with CMake:
+
+* **FetchContent**: Starting from CMake 3.11, you can use [`FetchContent`](
+  https://cmake.org/cmake/help/v3.30/module/FetchContent.html) to automatically
+  download {fmt} as a dependency at configure time:
+
+        include(FetchContent)
+
+        FetchContent_Declare(
+          fmt
+          GIT_REPOSITORY https://github.com/fmtlib/fmt
+          GIT_TAG        e69e5f977d458f2650bb346dadf2ad30c5320281) # 10.2.1
+        FetchContent_MakeAvailable(fmt)
+
+        target_link_libraries(<your-target> fmt::fmt)
+
+* **Installed**: You can find and use an [installed](#installation) version of
+  {fmt} in your `CMakeLists.txt` file as follows:
+
+        find_package(fmt)
+        target_link_libraries(<your-target> fmt::fmt)
+
+* **Embedded**: You can add the {fmt} source tree to your project and include it
+  in your `CMakeLists.txt` file:
+
+        add_subdirectory(fmt)
+        target_link_libraries(<your-target> fmt::fmt)
+
+## Installation
+
+### Debian/Ubuntu
+
+To install {fmt} on Debian, Ubuntu, or any other Debian-based Linux
+distribution, use the following command:
+
+    apt install libfmt-dev
+
+### Homebrew
+
+Install {fmt} on macOS using [Homebrew](https://brew.sh/):
+
+    brew install fmt
+
+### Conda
+
+Install {fmt} on Linux, macOS, and Windows with [Conda](
+https://docs.conda.io/en/latest/), using its [conda-forge package](
+https://github.com/conda-forge/fmt-feedstock):
+
+    conda install -c conda-forge fmt
+
+### vcpkg
+
+Download and install {fmt} using the vcpkg package manager:
+
+    git clone https://github.com/Microsoft/vcpkg.git
+    cd vcpkg
+    ./bootstrap-vcpkg.sh
+    ./vcpkg integrate install
+    ./vcpkg install fmt
+
+<!-- The fmt package in vcpkg is kept up to date by Microsoft team members and
+community contributors. If the version is out of date, please [create an
+issue or pull request](https://github.com/Microsoft/vcpkg) on the vcpkg
+repository. -->
+
+## Building from Source
+
+CMake works by generating native makefiles or project files that can be
+used in the compiler environment of your choice. The typical workflow
+starts with:
+
+    mkdir build  # Create a directory to hold the build output.
+    cd build
+    cmake ..     # Generate native build scripts.
+
+run in the `fmt` repository.
+
+If you are on a Unix-like system, you should now see a Makefile in the
+current directory. Now you can build the library by running `make`.
+
+Once the library has been built you can invoke `make test` to run the tests.
+
+You can control generation of the make `test` target with the `FMT_TEST`
+CMake option. This can be useful if you include fmt as a subdirectory in
+your project but don't want to add fmt's tests to your `test` target.
+
+To build a shared library set the `BUILD_SHARED_LIBS` CMake variable to `TRUE`:
+
+    cmake -DBUILD_SHARED_LIBS=TRUE ..
+
+To build a static library with position-independent code (e.g. for
+linking it into another shared library such as a Python extension), set the
+`CMAKE_POSITION_INDEPENDENT_CODE` CMake variable to `TRUE`:
+
+    cmake -DCMAKE_POSITION_INDEPENDENT_CODE=TRUE ..
+
+After building the library you can install it on a Unix-like system by
+running `sudo make install`.
+
+### Building the Docs
+
+To build the documentation you need the following software installed on
+your system:
+
+- [Python](https://www.python.org/)
+- [Doxygen](http://www.stack.nl/~dimitri/doxygen/)
+- [MkDocs](https://www.mkdocs.org/) with `mkdocs-material`, `mkdocstrings`,
+  `pymdown-extensions` and `mike`
+
+First generate makefiles or project files using CMake as described in
+the previous section. Then compile the `doc` target/project, for example:
+
+    make doc
+
+This will generate the HTML documentation in `doc/html`.
+
+## Build Systems
+
+### build2
+
+You can use [build2](https://build2.org), a dependency manager and a build
+system, to use {fmt}.
+
+Currently this package is available in these package repositories:
+
+- <https://cppget.org/fmt/> for released and published versions.
+- <https://github.com/build2-packaging/fmt> for unreleased or custom versions.
+
+**Usage:**
+
+- `build2` package name: `fmt`
+- Library target name: `lib{fmt}`
+
+To make your `build2` project depend on `fmt`:
+
+- Add one of the repositories to your configurations, or in your
+  `repositories.manifest`, if not already there:
+
+        :
+        role: prerequisite
+        location: https://pkg.cppget.org/1/stable
+
+- Add this package as a dependency to your `manifest` file (example
+  for version 10):
+
+        depends: fmt ~10.0.0
+
+- Import the target and use it as a prerequisite to your own target
+  using `fmt` in the appropriate `buildfile`:
+
+        import fmt = fmt%lib{fmt}
+        lib{mylib} : cxx{**} ... $fmt
+
+Then build your project as usual with `b` or `bdep update`.
+
+### Meson
+
+[Meson WrapDB](https://mesonbuild.com/Wrapdb-projects.html) includes an `fmt`
+package.
+
+**Usage:**
+
+- Install the `fmt` subproject from the WrapDB by running:
+
+        meson wrap install fmt
+
+  from the root of your project.
+
+- In your project's `meson.build` file, add an entry for the new subproject:
+
+        fmt = subproject('fmt')
+        fmt_dep = fmt.get_variable('fmt_dep')
+
+- Include the new dependency object to link with fmt:
+
+        my_build_target = executable(
+          'name', 'src/main.cc', dependencies: [fmt_dep])
+
+**Options:**
+
+If desired, {fmt} can be built as a static library, or as a header-only library.
+
+For a static build, use the following subproject definition:
+
+    fmt = subproject('fmt', default_options: 'default_library=static')
+    fmt_dep = fmt.get_variable('fmt_dep')
+
+For the header-only version, use:
+
+    fmt = subproject('fmt', default_options: ['header-only=true'])
+    fmt_dep = fmt.get_variable('fmt_header_only_dep')
+
+### Android NDK
+
+{fmt} provides [Android.mk file](
+https://github.com/fmtlib/fmt/blob/master/support/Android.mk) that can be used
+to build the library with [Android NDK](
+https://developer.android.com/tools/sdk/ndk/index.html).
+
+### Other
+
+To use the {fmt} library with any other build system, add
+`include/fmt/base.h`, `include/fmt/format.h`, `include/fmt/format-inl.h`,
+`src/format.cc` and optionally other headers from a [release archive](
+https://github.com/fmtlib/fmt/releases) or the [git repository](
+https://github.com/fmtlib/fmt) to your project, add `include` to include
+directories and make sure `src/format.cc` is compiled and linked with your code.

extlib/libfmt/doc/index.md

@@ -0,0 +1,151 @@
+---
+hide:
+  - navigation
+  - toc
+---
+
+# A modern formatting library
+
+<div class="features-container">
+
+<div class="feature">
+<h2>Safety</h2>
+<p>
+  Inspired by Python's formatting facility, {fmt} provides a safe replacement
+  for the <code>printf</code> family of functions. Errors in format strings,
+  which are a common source of vulnerabilities in C, are <b>reported at
+  compile time</b>. For example:
+
+  <pre><code class="language-cpp"
+  >fmt::format("{:d}", "I am not a number");</code></pre>
+
+  will give a compile-time error because <code>d</code> is not a valid
+  format specifier for strings. APIs like <a href="api/#format">
+  <code>fmt::format</code></a> <b>prevent buffer overflow errors</b> via
+  automatic memory management.
+</p>
+<a href="api#compile-time-checks">→ Learn more</a>
+</div>
+
+<div class="feature">
+<h2>Extensibility</h2>
+<p>
+  Formatting of most <b>standard types</b>, including all containers, dates,
+  and times is <b>supported out-of-the-box</b>. For example:
+  
+  <pre><code class="language-cpp"
+  >fmt::print("{}", std::vector{1, 2, 3});</code></pre>
+
+  prints the vector in a JSON-like format:
+
+  <pre><code>[1, 2, 3]</code></pre>
+
+  You can <b>make your own types formattable</b> and even make compile-time
+  checks work for them.
+</p>
+<a href="api#udt">→ Learn more</a>
+</div>
+
+<div class="feature">
+<h2>Performance</h2>
+<p>
+  {fmt} can be anywhere from <b>tens of percent to 20-30 times faster</b> than
+  iostreams and <code>sprintf</code>, especially for numeric formatting.
+
+<a href="https://github.com/fmtlib/fmt?tab=readme-ov-file#benchmarks">
+<img src="perf.svg">
+</a>
+
+  The library <b>minimizes dynamic memory allocations</b> and can optionally
+  <a href="api#compile-api">compile format strings</a> to optimal code.
+</p>
+</div>
+
+<div class="feature">
+<h2>Unicode support</h2>
+<p>
+  {fmt} provides <b>portable Unicode support</b> on major operating systems
+  with UTF-8 and <code>char</code> strings. For example:
+
+  <pre><code class="language-cpp"
+  >fmt::print("Слава Україні!");</code></pre>
+
+  will be printed correctly on Linux, macOS, and even Windows console,
+  irrespective of the codepages.
+</p>
+<p>
+  The default is <b>locale-independent</b>, but you can opt into localized
+  formatting and {fmt} makes it work with Unicode, addressing issues in the
+  standard libary.
+</p>
+</div>
+
+<div class="feature">
+<h2>Fast compilation</h2>
+<p>
+  The library makes extensive use of <b>type erasure</b> to achieve fast
+  compilation. <code>fmt/base.h</code> provides a subset of the API with
+  <b>minimal include dependencies</b> and enough functionality to replace
+  all uses of <code>*printf</code>.
+</p>
+<p>
+  Code using {fmt} is usually several times faster to compile than the
+  equivalent iostreams code, and while <code>printf</code> compiles faster
+  still, the gap is narrowing.
+</p>
+<a href=
+"https://github.com/fmtlib/fmt?tab=readme-ov-file#compile-time-and-code-bloat">
+→ Learn more</a>
+</div>
+
+<div class="feature">
+<h2>Small binary footprint</h2>
+<p>
+  Type erasure is also used to prevent template bloat, resulting in <b>compact
+  per-call binary code</b>. For example, a call to <code>fmt::print</code> with
+  a single argument is just <a href="https://godbolt.org/g/TZU4KF">a few
+  instructions</a>, comparable to <code>printf</code> despite adding
+  runtime safety, and much smaller than the equivalent iostreams code.
+</p>
+<p>
+  The library itself has small binary footprint and some components such as
+  floating-point formatting can be disabled to make it even smaller for
+  resource-constrained devices.
+</p>
+</div>
+
+<div class="feature">
+<h2>Portability</h2>
+<p>
+  {fmt} has a <b>small self-contained codebase</b> with the core consisting of
+  just three headers and no external dependencies.
+</p>
+<p>
+  The library is highly portable and requires only a minimal <b>subset of
+  C++11</b> features which are available in GCC 4.9, Clang 3.4, MSVC 19.10
+  (2017) and later. Newer compiler and standard library features are used
+  if available, and enable additional functionality.
+</p>
+<p>
+  Where possible, the output of formatting functions is <b>consistent across
+  platforms</b>.
+</p>
+</p>
+</div>
+
+<div class="feature">
+<h2>Open source</h2>
+<p>
+  {fmt} is in the top hundred open-source C++ libraries on GitHub and has
+  <a href="https://github.com/fmtlib/fmt/graphs/contributors">hundreds of
+  all-time contributors</a>.
+</p>
+<p>
+  The library is distributed under a permissive MIT
+  <a href="https://github.com/fmtlib/fmt#license">license</a> and is
+  <b>relied upon by many open-source projects</b>, including Blender, PyTorch,
+  Apple's FoundationDB, Windows Terminal, MongoDB, and others.
+</p>
+</div>
+
+</div>

extlib/libfmt/doc/perf.svg

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extlib/libfmt/doc/python-license.txt

@@ -0,0 +1,290 @@
+A. HISTORY OF THE SOFTWARE
+==========================
+
+Python was created in the early 1990s by Guido van Rossum at Stichting
+Mathematisch Centrum (CWI, see http://www.cwi.nl) in the Netherlands
+as a successor of a language called ABC.  Guido remains Python's
+principal author, although it includes many contributions from others.
+
+In 1995, Guido continued his work on Python at the Corporation for
+National Research Initiatives (CNRI, see http://www.cnri.reston.va.us)
+in Reston, Virginia where he released several versions of the
+software.
+
+In May 2000, Guido and the Python core development team moved to
+BeOpen.com to form the BeOpen PythonLabs team.  In October of the same
+year, the PythonLabs team moved to Digital Creations (now Zope
+Corporation, see http://www.zope.com).  In 2001, the Python Software
+Foundation (PSF, see http://www.python.org/psf/) was formed, a
+non-profit organization created specifically to own Python-related
+Intellectual Property.  Zope Corporation is a sponsoring member of
+the PSF.
+
+All Python releases are Open Source (see http://www.opensource.org for
+the Open Source Definition).  Historically, most, but not all, Python
+releases have also been GPL-compatible; the table below summarizes
+the various releases.
+
+    Release         Derived     Year        Owner       GPL-
+                    from                                compatible? (1)
+
+    0.9.0 thru 1.2              1991-1995   CWI         yes
+    1.3 thru 1.5.2  1.2         1995-1999   CNRI        yes
+    1.6             1.5.2       2000        CNRI        no
+    2.0             1.6         2000        BeOpen.com  no
+    1.6.1           1.6         2001        CNRI        yes (2)
+    2.1             2.0+1.6.1   2001        PSF         no
+    2.0.1           2.0+1.6.1   2001        PSF         yes
+    2.1.1           2.1+2.0.1   2001        PSF         yes
+    2.2             2.1.1       2001        PSF         yes
+    2.1.2           2.1.1       2002        PSF         yes
+    2.1.3           2.1.2       2002        PSF         yes
+    2.2.1           2.2         2002        PSF         yes
+    2.2.2           2.2.1       2002        PSF         yes
+    2.2.3           2.2.2       2003        PSF         yes
+    2.3             2.2.2       2002-2003   PSF         yes
+    2.3.1           2.3         2002-2003   PSF         yes
+    2.3.2           2.3.1       2002-2003   PSF         yes
+    2.3.3           2.3.2       2002-2003   PSF         yes
+    2.3.4           2.3.3       2004        PSF         yes
+    2.3.5           2.3.4       2005        PSF         yes
+    2.4             2.3         2004        PSF         yes
+    2.4.1           2.4         2005        PSF         yes
+    2.4.2           2.4.1       2005        PSF         yes
+    2.4.3           2.4.2       2006        PSF         yes
+    2.4.4           2.4.3       2006        PSF         yes
+    2.5             2.4         2006        PSF         yes
+    2.5.1           2.5         2007        PSF         yes
+    2.5.2           2.5.1       2008        PSF         yes
+    2.5.3           2.5.2       2008        PSF         yes
+    2.6             2.5         2008        PSF         yes
+    2.6.1           2.6         2008        PSF         yes
+    2.6.2           2.6.1       2009        PSF         yes
+    2.6.3           2.6.2       2009        PSF         yes
+    2.6.4           2.6.3       2009        PSF         yes
+    2.6.5           2.6.4       2010        PSF         yes
+    3.0             2.6         2008        PSF         yes
+    3.0.1           3.0         2009        PSF         yes
+    3.1             3.0.1       2009        PSF         yes
+    3.1.1           3.1         2009        PSF         yes
+    3.1.2           3.1.1       2010        PSF         yes
+    3.1.3           3.1.2       2010        PSF         yes
+    3.1.4           3.1.3       2011        PSF         yes
+    3.2             3.1         2011        PSF         yes
+    3.2.1           3.2         2011        PSF         yes
+    3.2.2           3.2.1       2011        PSF         yes
+    3.2.3           3.2.2       2012        PSF         yes
+    3.3.0           3.2         2012        PSF         yes
+
+Footnotes:
+
+(1) GPL-compatible doesn't mean that we're distributing Python under
+    the GPL.  All Python licenses, unlike the GPL, let you distribute
+    a modified version without making your changes open source.  The
+    GPL-compatible licenses make it possible to combine Python with
+    other software that is released under the GPL; the others don't.
+
+(2) According to Richard Stallman, 1.6.1 is not GPL-compatible,
+    because its license has a choice of law clause.  According to
+    CNRI, however, Stallman's lawyer has told CNRI's lawyer that 1.6.1
+    is "not incompatible" with the GPL.
+
+Thanks to the many outside volunteers who have worked under Guido's
+direction to make these releases possible.
+
+
+B. TERMS AND CONDITIONS FOR ACCESSING OR OTHERWISE USING PYTHON
+===============================================================
+
+PYTHON SOFTWARE FOUNDATION LICENSE VERSION 2
+--------------------------------------------
+
+1. This LICENSE AGREEMENT is between the Python Software Foundation
+("PSF"), and the Individual or Organization ("Licensee") accessing and
+otherwise using this software ("Python") in source or binary form and
+its associated documentation.
+
+2. Subject to the terms and conditions of this License Agreement, PSF hereby
+grants Licensee a nonexclusive, royalty-free, world-wide license to reproduce,
+analyze, test, perform and/or display publicly, prepare derivative works,
+distribute, and otherwise use Python alone or in any derivative version,
+provided, however, that PSF's License Agreement and PSF's notice of copyright,
+i.e., "Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
+2011, 2012 Python Software Foundation; All Rights Reserved" are retained in Python
+alone or in any derivative version prepared by Licensee.
+
+3. In the event Licensee prepares a derivative work that is based on
+or incorporates Python or any part thereof, and wants to make
+the derivative work available to others as provided herein, then
+Licensee hereby agrees to include in any such work a brief summary of
+the changes made to Python.
+
+4. PSF is making Python available to Licensee on an "AS IS"
+basis.  PSF MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
+IMPLIED.  BY WAY OF EXAMPLE, BUT NOT LIMITATION, PSF MAKES NO AND
+DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
+FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF PYTHON WILL NOT
+INFRINGE ANY THIRD PARTY RIGHTS.
+
+5. PSF SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON
+FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS
+A RESULT OF MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON,
+OR ANY DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+6. This License Agreement will automatically terminate upon a material
+breach of its terms and conditions.
+
+7. Nothing in this License Agreement shall be deemed to create any
+relationship of agency, partnership, or joint venture between PSF and
+Licensee.  This License Agreement does not grant permission to use PSF
+trademarks or trade name in a trademark sense to endorse or promote
+products or services of Licensee, or any third party.
+
+8. By copying, installing or otherwise using Python, Licensee
+agrees to be bound by the terms and conditions of this License
+Agreement.
+
+
+BEOPEN.COM LICENSE AGREEMENT FOR PYTHON 2.0
+-------------------------------------------
+
+BEOPEN PYTHON OPEN SOURCE LICENSE AGREEMENT VERSION 1
+
+1. This LICENSE AGREEMENT is between BeOpen.com ("BeOpen"), having an
+office at 160 Saratoga Avenue, Santa Clara, CA 95051, and the
+Individual or Organization ("Licensee") accessing and otherwise using
+this software in source or binary form and its associated
+documentation ("the Software").
+
+2. Subject to the terms and conditions of this BeOpen Python License
+Agreement, BeOpen hereby grants Licensee a non-exclusive,
+royalty-free, world-wide license to reproduce, analyze, test, perform
+and/or display publicly, prepare derivative works, distribute, and
+otherwise use the Software alone or in any derivative version,
+provided, however, that the BeOpen Python License is retained in the
+Software, alone or in any derivative version prepared by Licensee.
+
+3. BeOpen is making the Software available to Licensee on an "AS IS"
+basis.  BEOPEN MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
+IMPLIED.  BY WAY OF EXAMPLE, BUT NOT LIMITATION, BEOPEN MAKES NO AND
+DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
+FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF THE SOFTWARE WILL NOT
+INFRINGE ANY THIRD PARTY RIGHTS.
+
+4. BEOPEN SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF THE
+SOFTWARE FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS
+AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THE SOFTWARE, OR ANY
+DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+5. This License Agreement will automatically terminate upon a material
+breach of its terms and conditions.
+
+6. This License Agreement shall be governed by and interpreted in all
+respects by the law of the State of California, excluding conflict of
+law provisions.  Nothing in this License Agreement shall be deemed to
+create any relationship of agency, partnership, or joint venture
+between BeOpen and Licensee.  This License Agreement does not grant
+permission to use BeOpen trademarks or trade names in a trademark
+sense to endorse or promote products or services of Licensee, or any
+third party.  As an exception, the "BeOpen Python" logos available at
+http://www.pythonlabs.com/logos.html may be used according to the
+permissions granted on that web page.
+
+7. By copying, installing or otherwise using the software, Licensee
+agrees to be bound by the terms and conditions of this License
+Agreement.
+
+
+CNRI LICENSE AGREEMENT FOR PYTHON 1.6.1
+---------------------------------------
+
+1. This LICENSE AGREEMENT is between the Corporation for National
+Research Initiatives, having an office at 1895 Preston White Drive,
+Reston, VA 20191 ("CNRI"), and the Individual or Organization
+("Licensee") accessing and otherwise using Python 1.6.1 software in
+source or binary form and its associated documentation.
+
+2. Subject to the terms and conditions of this License Agreement, CNRI
+hereby grants Licensee a nonexclusive, royalty-free, world-wide
+license to reproduce, analyze, test, perform and/or display publicly,
+prepare derivative works, distribute, and otherwise use Python 1.6.1
+alone or in any derivative version, provided, however, that CNRI's
+License Agreement and CNRI's notice of copyright, i.e., "Copyright (c)
+1995-2001 Corporation for National Research Initiatives; All Rights
+Reserved" are retained in Python 1.6.1 alone or in any derivative
+version prepared by Licensee.  Alternately, in lieu of CNRI's License
+Agreement, Licensee may substitute the following text (omitting the
+quotes): "Python 1.6.1 is made available subject to the terms and
+conditions in CNRI's License Agreement.  This Agreement together with
+Python 1.6.1 may be located on the Internet using the following
+unique, persistent identifier (known as a handle): 1895.22/1013.  This
+Agreement may also be obtained from a proxy server on the Internet
+using the following URL: http://hdl.handle.net/1895.22/1013".
+
+3. In the event Licensee prepares a derivative work that is based on
+or incorporates Python 1.6.1 or any part thereof, and wants to make
+the derivative work available to others as provided herein, then
+Licensee hereby agrees to include in any such work a brief summary of
+the changes made to Python 1.6.1.
+
+4. CNRI is making Python 1.6.1 available to Licensee on an "AS IS"
+basis.  CNRI MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
+IMPLIED.  BY WAY OF EXAMPLE, BUT NOT LIMITATION, CNRI MAKES NO AND
+DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
+FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF PYTHON 1.6.1 WILL NOT
+INFRINGE ANY THIRD PARTY RIGHTS.
+
+5. CNRI SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON
+1.6.1 FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS
+A RESULT OF MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON 1.6.1,
+OR ANY DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+6. This License Agreement will automatically terminate upon a material
+breach of its terms and conditions.
+
+7. This License Agreement shall be governed by the federal
+intellectual property law of the United States, including without
+limitation the federal copyright law, and, to the extent such
+U.S. federal law does not apply, by the law of the Commonwealth of
+Virginia, excluding Virginia's conflict of law provisions.
+Notwithstanding the foregoing, with regard to derivative works based
+on Python 1.6.1 that incorporate non-separable material that was
+previously distributed under the GNU General Public License (GPL), the
+law of the Commonwealth of Virginia shall govern this License
+Agreement only as to issues arising under or with respect to
+Paragraphs 4, 5, and 7 of this License Agreement.  Nothing in this
+License Agreement shall be deemed to create any relationship of
+agency, partnership, or joint venture between CNRI and Licensee.  This
+License Agreement does not grant permission to use CNRI trademarks or
+trade name in a trademark sense to endorse or promote products or
+services of Licensee, or any third party.
+
+8. By clicking on the "ACCEPT" button where indicated, or by copying,
+installing or otherwise using Python 1.6.1, Licensee agrees to be
+bound by the terms and conditions of this License Agreement.
+
+        ACCEPT
+
+
+CWI LICENSE AGREEMENT FOR PYTHON 0.9.0 THROUGH 1.2
+--------------------------------------------------
+
+Copyright (c) 1991 - 1995, Stichting Mathematisch Centrum Amsterdam,
+The Netherlands.  All rights reserved.
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in
+supporting documentation, and that the name of Stichting Mathematisch
+Centrum or CWI not be used in advertising or publicity pertaining to
+distribution of the software without specific, written prior
+permission.
+
+STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
+THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
+FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

extlib/libfmt/doc/syntax.md

@@ -0,0 +1,886 @@
+# Format String Syntax
+
+Formatting functions such as [`fmt::format`](api.md#format) and [`fmt::print`](
+api.md#print) use the same format string syntax described in this section.
+
+Format strings contain "replacement fields" surrounded by curly braces `{}`.
+Anything that is not contained in braces is considered literal text, which is
+copied unchanged to the output. If you need to include a brace character in
+the literal text, it can be escaped by doubling: `{{` and `}}`.
+
+The grammar for a replacement field is as follows:
+
+<a id="replacement-field"></a>
+<pre><code class="language-json"
+>replacement_field ::= "{" [arg_id] [":" (<a href="#format-spec"
+  >format_spec</a> | <a href="#chrono-format-spec">chrono_format_spec</a>)] "}"
+arg_id            ::= integer | identifier
+integer           ::= digit+
+digit             ::= "0"..."9"
+identifier        ::= id_start id_continue*
+id_start          ::= "a"..."z" | "A"..."Z" | "_"
+id_continue       ::= id_start | digit</code>
+</pre>
+
+In less formal terms, the replacement field can start with an *arg_id* that
+specifies the argument whose value is to be formatted and inserted into the
+output instead of the replacement field. The *arg_id* is optionally followed
+by a *format_spec*, which is preceded by a colon `':'`. These specify a
+non-default format for the replacement value.
+
+See also the [Format Specification
+Mini-Language](#format-specification-mini-language) section.
+
+If the numerical arg_ids in a format string are 0, 1, 2, ... in sequence,
+they can all be omitted (not just some) and the numbers 0, 1, 2, ... will be
+automatically inserted in that order.
+
+Named arguments can be referred to by their names or indices.
+
+Some simple format string examples:
+
+```c++
+"First, thou shalt count to {0}" // References the first argument
+"Bring me a {}"                  // Implicitly references the first argument
+"From {} to {}"                  // Same as "From {0} to {1}"
+```
+
+The *format_spec* field contains a specification of how the value should
+be presented, including such details as field width, alignment, padding,
+decimal precision and so on. Each value type can define its own
+"formatting mini-language" or interpretation of the *format_spec*.
+
+Most built-in types support a common formatting mini-language, which is
+described in the next section.
+
+A *format_spec* field can also include nested replacement fields in
+certain positions within it. These nested replacement fields can contain
+only an argument id; format specifications are not allowed. This allows
+the formatting of a value to be dynamically specified.
+
+See the [Format Examples](#format-examples) section for some examples.
+
+## Format Specification Mini-Language
+
+"Format specifications" are used within replacement fields contained within a
+format string to define how individual values are presented. Each formattable
+type may define how the format specification is to be interpreted.
+
+Most built-in types implement the following options for format
+specifications, although some of the formatting options are only
+supported by the numeric types.
+
+The general form of a *standard format specifier* is:
+
+<a id="format-spec"></a>
+<pre><code class="language-json"
+>format_spec ::= [[fill]align][sign]["#"]["0"][width]["." precision]["L"][type]
+fill        ::= &lt;a character other than '{' or '}'>
+align       ::= "<" | ">" | "^"
+sign        ::= "+" | "-" | " "
+width       ::= <a href="#replacement-field">integer</a> | "{" [<a
+  href="#replacement-field">arg_id</a>] "}"
+precision   ::= <a href="#replacement-field">integer</a> | "{" [<a
+  href="#replacement-field">arg_id</a>] "}"
+type        ::= "a" | "A" | "b" | "B" | "c" | "d" | "e" | "E" | "f" | "F" |
+                "g" | "G" | "o" | "p" | "s" | "x" | "X" | "?"</code>
+</pre>
+
+The *fill* character can be any Unicode code point other than `'{'` or `'}'`.
+The presence of a fill character is signaled by the character following it,
+which must be one of the alignment options. If the second character of
+*format_spec* is not a valid alignment option, then it is assumed that both
+the fill character and the alignment option are absent.
+
+The meaning of the various alignment options is as follows:
+
+<table>
+<tr>
+  <th>Option</th>
+  <th>Meaning</th>
+</tr>
+<tr>
+  <td><code>'<'</code></td>
+  <td>
+    Forces the field to be left-aligned within the available space (this is the
+    default for most objects).
+  </td>
+</tr>
+<tr>
+  <td><code>'>'</code></td>
+  <td>
+    Forces the field to be right-aligned within the available space (this is
+    the default for numbers).
+  </td>
+</tr>
+<tr>
+  <td><code>'^'</code></td>
+  <td>Forces the field to be centered within the available space.</td>
+</tr>
+</table>
+
+Note that unless a minimum field width is defined, the field width will
+always be the same size as the data to fill it, so that the alignment
+option has no meaning in this case.
+
+The *sign* option is only valid for floating point and signed integer types,
+and can be one of the following:
+
+<table>
+<tr>
+  <th>Option</th>
+  <th>Meaning</th>
+</tr>
+<tr>
+  <td><code>'+'</code></td>
+  <td>
+    Indicates that a sign should be used for both nonnegative as well as
+    negative numbers.
+  </td>
+</tr>
+<tr>
+  <td><code>'-'</code></td>
+  <td>
+    Indicates that a sign should be used only for negative numbers (this is the
+    default behavior).
+  </td>
+</tr>
+<tr>
+  <td>space</td>
+  <td>
+    Indicates that a leading space should be used on nonnegative numbers, and a
+    minus sign on negative numbers.
+  </td>
+</tr>
+</table>
+
+The `'#'` option causes the "alternate form" to be used for the
+conversion. The alternate form is defined differently for different
+types. This option is only valid for integer and floating-point types.
+For integers, when binary, octal, or hexadecimal output is used, this
+option adds the prefix respective `"0b"` (`"0B"`), `"0"`, or `"0x"`
+(`"0X"`) to the output value. Whether the prefix is lower-case or
+upper-case is determined by the case of the type specifier, for example,
+the prefix `"0x"` is used for the type `'x'` and `"0X"` is used for
+`'X'`. For floating-point numbers the alternate form causes the result
+of the conversion to always contain a decimal-point character, even if
+no digits follow it. Normally, a decimal-point character appears in the
+result of these conversions only if a digit follows it. In addition, for
+`'g'` and `'G'` conversions, trailing zeros are not removed from the
+result.
+
+*width* is a decimal integer defining the minimum field width. If not
+specified, then the field width will be determined by the content.
+
+Preceding the *width* field by a zero (`'0'`) character enables
+sign-aware zero-padding for numeric types. It forces the padding to be
+placed after the sign or base (if any) but before the digits. This is
+used for printing fields in the form "+000000120". This option is only
+valid for numeric types and it has no effect on formatting of infinity
+and NaN. This option is ignored when any alignment specifier is present.
+
+The *precision* is a decimal number indicating how many digits should be
+displayed after the decimal point for a floating-point value formatted
+with `'f'` and `'F'`, or before and after the decimal point for a
+floating-point value formatted with `'g'` or `'G'`. For non-number types
+the field indicates the maximum field size - in other words, how many
+characters will be used from the field content. The *precision* is not
+allowed for integer, character, Boolean, and pointer values. Note that a
+C string must be null-terminated even if precision is specified.
+
+The `'L'` option uses the current locale setting to insert the appropriate
+number separator characters. This option is only valid for numeric types.
+
+Finally, the *type* determines how the data should be presented.
+
+The available string presentation types are:
+
+<table>
+<tr>
+  <th>Type</th>
+  <th>Meaning</th>
+</tr>
+<tr>
+  <td><code>'s'</code></td>
+  <td>
+    String format. This is the default type for strings and may be omitted.
+  </td>
+</tr>
+<tr>
+  <td><code>'?'</code></td>
+  <td>Debug format. The string is quoted and special characters escaped.</td>
+</tr>
+<tr>
+  <td>none</td>
+  <td>The same as <code>'s'</code>.</td>
+</tr>
+</table>
+
+The available character presentation types are:
+
+<table>
+<tr>
+  <th>Type</th>
+  <th>Meaning</th>
+</tr>
+<tr>
+  <td><code>'c'</code></td>
+  <td>
+    Character format. This is the default type for characters and may be
+    omitted.
+  </td>
+</tr>
+<tr>
+  <td><code>'?'</code></td>
+  <td>Debug format. The character is quoted and special characters escaped.</td>
+</tr>
+<tr>
+  <td>none</td>
+  <td>The same as <code>'c'</code>.</td>
+</tr>
+</table>
+
+The available integer presentation types are:
+
+<table>
+<tr>
+  <th>Type</th>
+  <th>Meaning</th>
+</tr>
+<tr>
+  <td><code>'b'</code></td>
+  <td>
+    Binary format. Outputs the number in base 2. Using the <code>'#'</code>
+    option with this type adds the prefix <code>"0b"</code> to the output value.    
+  </td>
+</tr>
+<tr>
+  <td><code>'B'</code></td>
+  <td>
+    Binary format. Outputs the number in base 2. Using the <code>'#'</code>
+    option with this type adds the prefix <code>"0B"</code> to the output value.
+  </td>
+</tr>
+<tr>
+  <td><code>'c'</code></td>
+  <td>Character format. Outputs the number as a character.</td>
+</tr>
+<tr>
+  <td><code>'d'</code></td>
+  <td>Decimal integer. Outputs the number in base 10.</td>
+</tr>
+<tr>
+  <td><code>'o'</code></td>
+  <td>Octal format. Outputs the number in base 8.</td>
+</tr>
+<tr>
+  <td><code>'x'</code></td>
+  <td>
+    Hex format. Outputs the number in base 16, using lower-case letters for the
+    digits above 9. Using the <code>'#'</code> option with this type adds the
+    prefix <code>"0x"</code> to the output value.
+  </td>
+</tr>
+<tr>
+  <td><code>'X'</code></td>
+  <td>
+    Hex format. Outputs the number in base 16, using upper-case letters for the
+    digits above 9. Using the <code>'#'</code> option with this type adds the
+    prefix <code>"0X"</code> to the output value.
+  </td>
+</tr>
+<tr>
+  <td>none</td>
+  <td>The same as <code>'d'</code>.</td>
+</tr>
+</table>
+
+Integer presentation types can also be used with character and Boolean values
+with the only exception that `'c'` cannot be used with `bool`. Boolean values
+are formatted using textual representation, either `true` or `false`, if the
+presentation type is not specified.
+
+The available presentation types for floating-point values are:
+
+<table>
+<tr>
+  <th>Type</th>
+  <th>Meaning</th>
+</tr>
+<tr>
+  <td><code>'a'</code></td>
+  <td>
+    Hexadecimal floating point format. Prints the number in base 16 with
+    prefix <code>"0x"</code> and lower-case letters for digits above 9.
+    Uses <code>'p'</code> to indicate the exponent.
+  </td>
+</tr>
+<tr>
+  <td><code>'A'</code></td>
+  <td>
+    Same as <code>'a'</code> except it uses upper-case letters for the
+    prefix, digits above 9 and to indicate the exponent.
+  </td>
+</tr>
+<tr>
+  <td><code>'e'</code></td>
+  <td>
+    Exponent notation. Prints the number in scientific notation using
+    the letter 'e' to indicate the exponent.
+  </td>
+</tr>
+<tr>
+  <td><code>'E'</code></td>
+  <td>
+    Exponent notation. Same as <code>'e'</code> except it uses an
+    upper-case <code>'E'</code> as the separator character.
+  </td>
+</tr>
+<tr>
+  <td><code>'f'</code></td>
+  <td>Fixed point. Displays the number as a fixed-point number.</td>
+</tr>
+<tr>
+  <td><code>'F'</code></td>
+  <td>
+    Fixed point. Same as <code>'f'</code>, but converts <code>nan</code>
+    to <code>NAN</code> and <code>inf</code> to <code>INF</code>.
+  </td>
+</tr>
+<tr>
+  <td><code>'g'</code></td>
+  <td>
+    <p>General format. For a given precision <code>p &gt;= 1</code>,
+    this rounds the number to <code>p</code> significant digits and then
+    formats the result in either fixed-point format or in scientific
+    notation, depending on its magnitude.</p>
+    <p>A precision of <code>0</code> is treated as equivalent to a precision
+    of <code>1</code>.</p>
+  </td>
+</tr>
+<tr>
+  <td><code>'G'</code></td>
+  <td>
+    General format. Same as <code>'g'</code> except switches to
+    <code>'E'</code> if the number gets too large. The representations of
+    infinity and NaN are uppercased, too.
+  </td>
+</tr>
+<tr>
+  <td>none</td>
+  <td>
+    Similar to <code>'g'</code>, except that the default precision is as
+    high as needed to represent the particular value.
+  </td>
+</tr>
+</table>
+
+The available presentation types for pointers are:
+
+<table>
+<tr>
+  <th>Type</th>
+  <th>Meaning</th>
+</tr>
+<tr>
+  <td><code>'p'</code></td>
+  <td>
+    Pointer format. This is the default type for pointers and may be omitted.
+  </td>
+</tr>
+<tr>
+  <td>none</td>
+  <td>The same as <code>'p'</code>.</td>
+</tr>
+</table>
+
+## Chrono Format Specifications
+
+Format specifications for chrono duration and time point types as well as
+`std::tm` have the following syntax:
+
+<a id="chrono-format-spec"></a>
+<pre><code class="language-json"
+>chrono_format_spec ::= [[<a href="#format-spec">fill</a>]<a href="#format-spec"
+  >align</a>][<a href="#format-spec">width</a>]["." <a href="#format-spec"
+  >precision</a>][chrono_specs]
+chrono_specs       ::= conversion_spec |
+                       chrono_specs (conversion_spec | literal_char)
+conversion_spec    ::= "%" [padding_modifier] [locale_modifier] chrono_type
+literal_char       ::= &lt;a character other than '{', '}' or '%'>
+padding_modifier   ::= "-" | "_"  | "0"
+locale_modifier    ::= "E" | "O"
+chrono_type        ::= "a" | "A" | "b" | "B" | "c" | "C" | "d" | "D" | "e" |
+                       "F" | "g" | "G" | "h" | "H" | "I" | "j" | "m" | "M" |
+                       "n" | "p" | "q" | "Q" | "r" | "R" | "S" | "t" | "T" |
+                       "u" | "U" | "V" | "w" | "W" | "x" | "X" | "y" | "Y" |
+                       "z" | "Z" | "%"</code>
+</pre>
+
+Literal chars are copied unchanged to the output. Precision is valid only
+for `std::chrono::duration` types with a floating-point representation type.
+
+The available presentation types (*chrono_type*) are:
+
+<table>
+<tr>
+  <th>Type</th>
+  <th>Meaning</th>
+</tr>
+<tr>
+  <td><code>'a'</code></td>
+  <td>
+    The abbreviated weekday name, e.g. "Sat". If the value does not contain a
+    valid weekday, an exception of type <code>format_error</code> is thrown.
+  </td>
+</tr>
+<tr>
+  <td><code>'A'</code></td>
+  <td>
+    The full weekday name, e.g. "Saturday". If the value does not contain a
+    valid weekday, an exception of type <code>format_error</code> is thrown.
+  </td>
+</tr>
+<tr>
+  <td><code>'b'</code></td>
+  <td>
+    The abbreviated month name, e.g. "Nov". If the value does not contain a
+    valid month, an exception of type <code>format_error</code> is thrown.
+  </td>
+</tr>
+<tr>
+  <td><code>'B'</code></td>
+  <td>
+    The full month name, e.g. "November". If the value does not contain a valid
+    month, an exception of type <code>format_error</code> is thrown.
+  </td>
+</tr>
+<tr>
+  <td><code>'c'</code></td>
+  <td>
+    The date and time representation, e.g. "Sat Nov 12 22:04:00 1955". The
+    modified command <code>%Ec</code> produces the locale's alternate date and
+    time representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'C'</code></td>
+  <td>
+    The year divided by 100 using floored division, e.g. "19". If the result
+    is a single decimal digit, it is prefixed with 0. The modified command
+    <code>%EC</code> produces the locale's alternative representation of the
+    century.
+  </td>
+</tr>
+<tr>
+  <td><code>'d'</code></td>
+  <td>
+    The day of month as a decimal number. If the result is a single decimal
+    digit, it is prefixed with 0. The modified command <code>%Od</code>
+    produces the locale's alternative representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'D'</code></td>
+  <td>Equivalent to <code>%m/%d/%y</code>, e.g. "11/12/55".</td>
+</tr>
+<tr>
+  <td><code>'e'</code></td>
+  <td>
+    The day of month as a decimal number. If the result is a single decimal
+    digit, it is prefixed with a space. The modified command <code>%Oe</code>
+    produces the locale's alternative representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'F'</code></td>
+  <td>Equivalent to <code>%Y-%m-%d</code>, e.g. "1955-11-12".</td>
+</tr>
+<tr>
+  <td><code>'g'</code></td>
+  <td>
+    The last two decimal digits of the ISO week-based year. If the result is a
+    single digit it is prefixed by 0.
+  </td>
+</tr>
+<tr>
+  <td><code>'G'</code></td>
+  <td>
+    The ISO week-based year as a decimal number. If the result is less than
+    four digits it is left-padded with 0 to four digits.
+  </td>
+</tr>
+<tr>
+  <td><code>'h'</code></td>
+  <td>Equivalent to <code>%b</code>, e.g. "Nov".</td>
+</tr>
+<tr>
+  <td><code>'H'</code></td>
+  <td>
+    The hour (24-hour clock) as a decimal number. If the result is a single
+    digit, it is prefixed with 0. The modified command <code>%OH</code>
+    produces the locale's alternative representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'I'</code></td>
+  <td>
+    The hour (12-hour clock) as a decimal number. If the result is a single
+    digit, it is prefixed with 0. The modified command <code>%OI</code>
+    produces the locale's alternative representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'j'</code></td>
+  <td>
+    If the type being formatted is a specialization of duration, the decimal
+    number of days without padding. Otherwise, the day of the year as a decimal
+    number. Jan 1 is 001. If the result is less than three digits, it is
+    left-padded with 0 to three digits.
+  </td>
+</tr>
+<tr>
+  <td><code>'m'</code></td>
+  <td>
+    The month as a decimal number. Jan is 01. If the result is a single digit,
+    it is prefixed with 0. The modified command <code>%Om</code> produces the
+    locale's alternative representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'M'</code></td>
+  <td>
+    The minute as a decimal number. If the result is a single digit, it
+    is prefixed with 0. The modified command <code>%OM</code> produces the
+    locale's alternative representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'n'</code></td>
+  <td>A new-line character.</td>
+</tr>
+<tr>
+  <td><code>'p'</code></td>
+  <td>The AM/PM designations associated with a 12-hour clock.</td>
+</tr>
+<tr>
+  <td><code>'q'</code></td>
+  <td>The duration's unit suffix.</td>
+</tr>
+<tr>
+  <td><code>'Q'</code></td>
+  <td>
+    The duration's numeric value (as if extracted via <code>.count()</code>).
+  </td>
+</tr>
+<tr>
+  <td><code>'r'</code></td>
+  <td>The 12-hour clock time, e.g. "10:04:00 PM".</td>
+</tr>
+<tr>
+  <td><code>'R'</code></td>
+  <td>Equivalent to <code>%H:%M</code>, e.g. "22:04".</td>
+</tr>
+<tr>
+  <td><code>'S'</code></td>
+  <td>
+    Seconds as a decimal number. If the number of seconds is less than 10, the
+    result is prefixed with 0. If the precision of the input cannot be exactly
+    represented with seconds, then the format is a decimal floating-point number
+    with a fixed format and a precision matching that of the precision of the
+    input (or to a microseconds precision if the conversion to floating-point
+    decimal seconds cannot be made within 18 fractional digits). The modified
+    command <code>%OS</code> produces the locale's alternative representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'t'</code></td>
+  <td>A horizontal-tab character.</td>
+</tr>
+<tr>
+  <td><code>'T'</code></td>
+  <td>Equivalent to <code>%H:%M:%S</code>.</td>
+</tr>
+<tr>
+  <td><code>'u'</code></td>
+  <td>
+    The ISO weekday as a decimal number (1-7), where Monday is 1. The modified
+    command <code>%Ou</code> produces the locale's alternative representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'U'</code></td>
+  <td>
+    The week number of the year as a decimal number. The first Sunday of the
+    year is the first day of week 01. Days of the same year prior to that are
+    in week 00. If the result is a single digit, it is prefixed with 0.
+    The modified command <code>%OU</code> produces the locale's alternative
+    representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'V'</code></td>
+  <td>
+    The ISO week-based week number as a decimal number. If the result is a
+    single digit, it is prefixed with 0. The modified command <code>%OV</code>
+    produces the locale's alternative representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'w'</code></td>
+  <td>
+    The weekday as a decimal number (0-6), where Sunday is 0. The modified
+    command <code>%Ow</code> produces the locale's alternative representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'W'</code></td>
+  <td>
+    The week number of the year as a decimal number. The first Monday of the
+    year is the first day of week 01. Days of the same year prior to that are
+    in week 00. If the result is a single digit, it is prefixed with 0.
+    The modified command <code>%OW</code> produces the locale's alternative
+    representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'x'</code></td>
+  <td>
+    The date representation, e.g. "11/12/55". The modified command
+    <code>%Ex</code> produces the locale's alternate date representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'X'</code></td>
+  <td>
+    The time representation, e.g. "10:04:00". The modified command
+    <code>%EX</code> produces the locale's alternate time representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'y'</code></td>
+  <td>
+    The last two decimal digits of the year. If the result is a single digit
+    it is prefixed by 0. The modified command <code>%Oy</code> produces the
+    locale's alternative representation. The modified command <code>%Ey</code>
+    produces the locale's alternative representation of offset from
+    <code>%EC</code> (year only).
+  </td>
+</tr>
+<tr>
+  <td><code>'Y'</code></td>
+  <td>
+    The year as a decimal number. If the result is less than four digits it is
+    left-padded with 0 to four digits. The modified command <code>%EY</code>
+    produces the locale's alternative full year representation.
+  </td>
+</tr>
+<tr>
+  <td><code>'z'</code></td>
+  <td>
+    The offset from UTC in the ISO 8601:2004 format. For example -0430 refers
+    to 4 hours 30 minutes behind UTC. If the offset is zero, +0000 is used.
+    The modified commands <code>%Ez</code> and <code>%Oz</code> insert a
+    <code>:</code> between the hours and minutes: -04:30. If the offset
+    information is not available, an exception of type
+    <code>format_error</code> is thrown.
+  </td>
+</tr>
+<tr>
+  <td><code>'Z'</code></td>
+  <td>
+    The time zone abbreviation. If the time zone abbreviation is not available,
+    an exception of type <code>format_error</code> is thrown.
+  </td>
+</tr>
+<tr>
+  <td><code>'%'</code></td>
+  <td>A % character.</td>
+</tr>
+</table>
+
+Specifiers that have a calendaric component such as `'d'` (the day of month)
+are valid only for `std::tm` and time points but not durations.
+
+The available padding modifiers (*padding_modifier*) are:
+
+| Type  | Meaning                                 |
+|-------|-----------------------------------------|
+| `'_'` | Pad a numeric result with spaces.       |
+| `'-'` | Do not pad a numeric result string.     |
+| `'0'` | Pad a numeric result string with zeros. |
+
+These modifiers are only supported for the `'H'`, `'I'`, `'M'`, `'S'`, `'U'`,
+`'V'`, `'W'`, `'Y'`, `'d'`, `'j'` and `'m'` presentation types.
+
+## Range Format Specifications
+
+Format specifications for range types have the following syntax:
+
+<pre><code class="language-json"
+>range_format_spec ::= ["n"][range_type][range_underlying_spec]</code>
+</pre>
+
+The `'n'` option formats the range without the opening and closing brackets.
+
+The available presentation types for `range_type` are:
+
+| Type   | Meaning                                                    |
+|--------|------------------------------------------------------------|
+| none   | Default format.                                            |
+| `'s'`  | String format. The range is formatted as a string.         |
+| `'?⁠s'` | Debug format. The range is formatted as an escaped string. |
+
+If `range_type` is `'s'` or `'?s'`, the range element type must be a character
+type. The `'n'` option and `range_underlying_spec` are mutually exclusive with
+`'s'` and `'?s'`.
+
+The `range_underlying_spec` is parsed based on the formatter of the range's
+element type.
+
+By default, a range of characters or strings is printed escaped and quoted.
+But if any `range_underlying_spec` is provided (even if it is empty), then the
+characters or strings are printed according to the provided specification.
+
+Examples:
+
+```c++
+fmt::print("{}", std::vector{10, 20, 30});
+// Output: [10, 20, 30]
+fmt::print("{::#x}", std::vector{10, 20, 30});
+// Output: [0xa, 0x14, 0x1e]
+fmt::print("{}", std::vector{'h', 'e', 'l', 'l', 'o'});
+// Output: ['h', 'e', 'l', 'l', 'o']
+fmt::print("{:n}", std::vector{'h', 'e', 'l', 'l', 'o'});
+// Output: 'h', 'e', 'l', 'l', 'o'
+fmt::print("{:s}", std::vector{'h', 'e', 'l', 'l', 'o'});
+// Output: "hello"
+fmt::print("{:?s}", std::vector{'h', 'e', 'l', 'l', 'o', '\n'});
+// Output: "hello\n"
+fmt::print("{::}", std::vector{'h', 'e', 'l', 'l', 'o'});
+// Output: [h, e, l, l, o]
+fmt::print("{::d}", std::vector{'h', 'e', 'l', 'l', 'o'});
+// Output: [104, 101, 108, 108, 111]
+```
+
+## Format Examples
+
+This section contains examples of the format syntax and comparison with
+the printf formatting.
+
+In most of the cases the syntax is similar to the printf formatting,
+with the addition of the `{}` and with `:` used instead of `%`. For
+example, `"%03.2f"` can be translated to `"{:03.2f}"`.
+
+The new format syntax also supports new and different options, shown in
+the following examples.
+
+Accessing arguments by position:
+
+```c++
+fmt::format("{0}, {1}, {2}", 'a', 'b', 'c');
+// Result: "a, b, c"
+fmt::format("{}, {}, {}", 'a', 'b', 'c');
+// Result: "a, b, c"
+fmt::format("{2}, {1}, {0}", 'a', 'b', 'c');
+// Result: "c, b, a"
+fmt::format("{0}{1}{0}", "abra", "cad");  // arguments' indices can be repeated
+// Result: "abracadabra"
+```
+
+Aligning the text and specifying a width:
+
+```c++
+fmt::format("{:<30}", "left aligned");
+// Result: "left aligned                  "
+fmt::format("{:>30}", "right aligned");
+// Result: "                 right aligned"
+fmt::format("{:^30}", "centered");
+// Result: "           centered           "
+fmt::format("{:*^30}", "centered");  // use '*' as a fill char
+// Result: "***********centered***********"
+```
+
+Dynamic width:
+
+```c++
+fmt::format("{:<{}}", "left aligned", 30);
+// Result: "left aligned                  "
+```
+
+Dynamic precision:
+
+```c++
+fmt::format("{:.{}f}", 3.14, 1);
+// Result: "3.1"
+```
+
+Replacing `%+f`, `%-f`, and `% f` and specifying a sign:
+
+```c++
+fmt::format("{:+f}; {:+f}", 3.14, -3.14);  // show it always
+// Result: "+3.140000; -3.140000"
+fmt::format("{: f}; {: f}", 3.14, -3.14);  // show a space for positive numbers
+// Result: " 3.140000; -3.140000"
+fmt::format("{:-f}; {:-f}", 3.14, -3.14);  // show only the minus -- same as '{:f}; {:f}'
+// Result: "3.140000; -3.140000"
+```
+
+Replacing `%x` and `%o` and converting the value to different bases:
+
+```c++
+fmt::format("int: {0:d};  hex: {0:x};  oct: {0:o}; bin: {0:b}", 42);
+// Result: "int: 42;  hex: 2a;  oct: 52; bin: 101010"
+// with 0x or 0 or 0b as prefix:
+fmt::format("int: {0:d};  hex: {0:#x};  oct: {0:#o};  bin: {0:#b}", 42);
+// Result: "int: 42;  hex: 0x2a;  oct: 052;  bin: 0b101010"
+```
+
+Padded hex byte with prefix and always prints both hex characters:
+
+```c++
+fmt::format("{:#04x}", 0);
+// Result: "0x00"
+```
+
+Box drawing using Unicode fill:
+
+```c++
+fmt::print(
+    "┌{0:─^{2}}┐\n"
+    "│{1: ^{2}}│\n"
+    "└{0:─^{2}}┘\n", "", "Hello, world!", 20);
+```
+
+prints:
+
+```
+┌────────────────────┐
+│   Hello, world!    │
+└────────────────────┘
+```
+
+Using type-specific formatting:
+
+```c++
+#include <fmt/chrono.h>
+
+auto t = tm();
+t.tm_year = 2010 - 1900;
+t.tm_mon = 7;
+t.tm_mday = 4;
+t.tm_hour = 12;
+t.tm_min = 15;
+t.tm_sec = 58;
+fmt::print("{:%Y-%m-%d %H:%M:%S}", t);
+// Prints: 2010-08-04 12:15:58
+```
+
+Using the comma as a thousands separator:
+
+```c++
+#include <fmt/format.h>
+
+auto s = fmt::format(std::locale("en_US.UTF-8"), "{:L}", 1234567890);
+// s == "1,234,567,890"
+```

extlib/libfmt/include/fmt/args.h

@@ -0,0 +1,220 @@
+// Formatting library for C++ - dynamic argument lists
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_ARGS_H_
+#define FMT_ARGS_H_
+
+#ifndef FMT_MODULE
+#  include <functional>  // std::reference_wrapper
+#  include <memory>      // std::unique_ptr
+#  include <vector>
+#endif
+
+#include "format.h"  // std_string_view
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template <typename T> struct is_reference_wrapper : std::false_type {};
+template <typename T>
+struct is_reference_wrapper<std::reference_wrapper<T>> : std::true_type {};
+
+template <typename T> auto unwrap(const T& v) -> const T& { return v; }
+template <typename T>
+auto unwrap(const std::reference_wrapper<T>& v) -> const T& {
+  return static_cast<const T&>(v);
+}
+
+// node is defined outside dynamic_arg_list to workaround a C2504 bug in MSVC
+// 2022 (v17.10.0).
+//
+// Workaround for clang's -Wweak-vtables. Unlike for regular classes, for
+// templates it doesn't complain about inability to deduce single translation
+// unit for placing vtable. So node is made a fake template.
+template <typename = void> struct node {
+  virtual ~node() = default;
+  std::unique_ptr<node<>> next;
+};
+
+class dynamic_arg_list {
+  template <typename T> struct typed_node : node<> {
+    T value;
+
+    template <typename Arg>
+    FMT_CONSTEXPR typed_node(const Arg& arg) : value(arg) {}
+
+    template <typename Char>
+    FMT_CONSTEXPR typed_node(const basic_string_view<Char>& arg)
+        : value(arg.data(), arg.size()) {}
+  };
+
+  std::unique_ptr<node<>> head_;
+
+ public:
+  template <typename T, typename Arg> auto push(const Arg& arg) -> const T& {
+    auto new_node = std::unique_ptr<typed_node<T>>(new typed_node<T>(arg));
+    auto& value = new_node->value;
+    new_node->next = std::move(head_);
+    head_ = std::move(new_node);
+    return value;
+  }
+};
+}  // namespace detail
+
+/**
+ * A dynamic list of formatting arguments with storage.
+ *
+ * It can be implicitly converted into `fmt::basic_format_args` for passing
+ * into type-erased formatting functions such as `fmt::vformat`.
+ */
+template <typename Context> class dynamic_format_arg_store {
+ private:
+  using char_type = typename Context::char_type;
+
+  template <typename T> struct need_copy {
+    static constexpr detail::type mapped_type =
+        detail::mapped_type_constant<T, char_type>::value;
+
+    enum {
+      value = !(detail::is_reference_wrapper<T>::value ||
+                std::is_same<T, basic_string_view<char_type>>::value ||
+                std::is_same<T, detail::std_string_view<char_type>>::value ||
+                (mapped_type != detail::type::cstring_type &&
+                 mapped_type != detail::type::string_type &&
+                 mapped_type != detail::type::custom_type))
+    };
+  };
+
+  template <typename T>
+  using stored_t = conditional_t<
+      std::is_convertible<T, std::basic_string<char_type>>::value &&
+          !detail::is_reference_wrapper<T>::value,
+      std::basic_string<char_type>, T>;
+
+  // Storage of basic_format_arg must be contiguous.
+  std::vector<basic_format_arg<Context>> data_;
+  std::vector<detail::named_arg_info<char_type>> named_info_;
+
+  // Storage of arguments not fitting into basic_format_arg must grow
+  // without relocation because items in data_ refer to it.
+  detail::dynamic_arg_list dynamic_args_;
+
+  friend class basic_format_args<Context>;
+
+  auto data() const -> const basic_format_arg<Context>* {
+    return named_info_.empty() ? data_.data() : data_.data() + 1;
+  }
+
+  template <typename T> void emplace_arg(const T& arg) {
+    data_.emplace_back(arg);
+  }
+
+  template <typename T>
+  void emplace_arg(const detail::named_arg<char_type, T>& arg) {
+    if (named_info_.empty())
+      data_.insert(data_.begin(), basic_format_arg<Context>(nullptr, 0));
+    data_.emplace_back(detail::unwrap(arg.value));
+    auto pop_one = [](std::vector<basic_format_arg<Context>>* data) {
+      data->pop_back();
+    };
+    std::unique_ptr<std::vector<basic_format_arg<Context>>, decltype(pop_one)>
+        guard{&data_, pop_one};
+    named_info_.push_back({arg.name, static_cast<int>(data_.size() - 2u)});
+    data_[0] = {named_info_.data(), named_info_.size()};
+    guard.release();
+  }
+
+ public:
+  constexpr dynamic_format_arg_store() = default;
+
+  operator basic_format_args<Context>() const {
+    return basic_format_args<Context>(data(), static_cast<int>(data_.size()),
+                                      !named_info_.empty());
+  }
+
+  /**
+   * Adds an argument into the dynamic store for later passing to a formatting
+   * function.
+   *
+   * Note that custom types and string types (but not string views) are copied
+   * into the store dynamically allocating memory if necessary.
+   *
+   * **Example**:
+   *
+   *     fmt::dynamic_format_arg_store<fmt::format_context> store;
+   *     store.push_back(42);
+   *     store.push_back("abc");
+   *     store.push_back(1.5f);
+   *     std::string result = fmt::vformat("{} and {} and {}", store);
+   */
+  template <typename T> void push_back(const T& arg) {
+    if (detail::const_check(need_copy<T>::value))
+      emplace_arg(dynamic_args_.push<stored_t<T>>(arg));
+    else
+      emplace_arg(detail::unwrap(arg));
+  }
+
+  /**
+   * Adds a reference to the argument into the dynamic store for later passing
+   * to a formatting function.
+   *
+   * **Example**:
+   *
+   *     fmt::dynamic_format_arg_store<fmt::format_context> store;
+   *     char band[] = "Rolling Stones";
+   *     store.push_back(std::cref(band));
+   *     band[9] = 'c'; // Changing str affects the output.
+   *     std::string result = fmt::vformat("{}", store);
+   *     // result == "Rolling Scones"
+   */
+  template <typename T> void push_back(std::reference_wrapper<T> arg) {
+    static_assert(
+        need_copy<T>::value,
+        "objects of built-in types and string views are always copied");
+    emplace_arg(arg.get());
+  }
+
+  /**
+   * Adds named argument into the dynamic store for later passing to a
+   * formatting function. `std::reference_wrapper` is supported to avoid
+   * copying of the argument. The name is always copied into the store.
+   */
+  template <typename T>
+  void push_back(const detail::named_arg<char_type, T>& arg) {
+    const char_type* arg_name =
+        dynamic_args_.push<std::basic_string<char_type>>(arg.name).c_str();
+    if (detail::const_check(need_copy<T>::value)) {
+      emplace_arg(
+          fmt::arg(arg_name, dynamic_args_.push<stored_t<T>>(arg.value)));
+    } else {
+      emplace_arg(fmt::arg(arg_name, arg.value));
+    }
+  }
+
+  /// Erase all elements from the store.
+  void clear() {
+    data_.clear();
+    named_info_.clear();
+    dynamic_args_ = {};
+  }
+
+  /// Reserves space to store at least `new_cap` arguments including
+  /// `new_cap_named` named arguments.
+  void reserve(size_t new_cap, size_t new_cap_named) {
+    FMT_ASSERT(new_cap >= new_cap_named,
+               "set of arguments includes set of named arguments");
+    data_.reserve(new_cap);
+    named_info_.reserve(new_cap_named);
+  }
+
+  /// Returns the number of elements in the store.
+  size_t size() const noexcept { return data_.size(); }
+};
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_ARGS_H_

extlib/libfmt/include/fmt/color.h

@@ -0,0 +1,610 @@
+// Formatting library for C++ - color support
+//
+// Copyright (c) 2018 - present, Victor Zverovich and fmt contributors
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_COLOR_H_
+#define FMT_COLOR_H_
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+FMT_BEGIN_EXPORT
+
+enum class color : uint32_t {
+  alice_blue = 0xF0F8FF,               // rgb(240,248,255)
+  antique_white = 0xFAEBD7,            // rgb(250,235,215)
+  aqua = 0x00FFFF,                     // rgb(0,255,255)
+  aquamarine = 0x7FFFD4,               // rgb(127,255,212)
+  azure = 0xF0FFFF,                    // rgb(240,255,255)
+  beige = 0xF5F5DC,                    // rgb(245,245,220)
+  bisque = 0xFFE4C4,                   // rgb(255,228,196)
+  black = 0x000000,                    // rgb(0,0,0)
+  blanched_almond = 0xFFEBCD,          // rgb(255,235,205)
+  blue = 0x0000FF,                     // rgb(0,0,255)
+  blue_violet = 0x8A2BE2,              // rgb(138,43,226)
+  brown = 0xA52A2A,                    // rgb(165,42,42)
+  burly_wood = 0xDEB887,               // rgb(222,184,135)
+  cadet_blue = 0x5F9EA0,               // rgb(95,158,160)
+  chartreuse = 0x7FFF00,               // rgb(127,255,0)
+  chocolate = 0xD2691E,                // rgb(210,105,30)
+  coral = 0xFF7F50,                    // rgb(255,127,80)
+  cornflower_blue = 0x6495ED,          // rgb(100,149,237)
+  cornsilk = 0xFFF8DC,                 // rgb(255,248,220)
+  crimson = 0xDC143C,                  // rgb(220,20,60)
+  cyan = 0x00FFFF,                     // rgb(0,255,255)
+  dark_blue = 0x00008B,                // rgb(0,0,139)
+  dark_cyan = 0x008B8B,                // rgb(0,139,139)
+  dark_golden_rod = 0xB8860B,          // rgb(184,134,11)
+  dark_gray = 0xA9A9A9,                // rgb(169,169,169)
+  dark_green = 0x006400,               // rgb(0,100,0)
+  dark_khaki = 0xBDB76B,               // rgb(189,183,107)
+  dark_magenta = 0x8B008B,             // rgb(139,0,139)
+  dark_olive_green = 0x556B2F,         // rgb(85,107,47)
+  dark_orange = 0xFF8C00,              // rgb(255,140,0)
+  dark_orchid = 0x9932CC,              // rgb(153,50,204)
+  dark_red = 0x8B0000,                 // rgb(139,0,0)
+  dark_salmon = 0xE9967A,              // rgb(233,150,122)
+  dark_sea_green = 0x8FBC8F,           // rgb(143,188,143)
+  dark_slate_blue = 0x483D8B,          // rgb(72,61,139)
+  dark_slate_gray = 0x2F4F4F,          // rgb(47,79,79)
+  dark_turquoise = 0x00CED1,           // rgb(0,206,209)
+  dark_violet = 0x9400D3,              // rgb(148,0,211)
+  deep_pink = 0xFF1493,                // rgb(255,20,147)
+  deep_sky_blue = 0x00BFFF,            // rgb(0,191,255)
+  dim_gray = 0x696969,                 // rgb(105,105,105)
+  dodger_blue = 0x1E90FF,              // rgb(30,144,255)
+  fire_brick = 0xB22222,               // rgb(178,34,34)
+  floral_white = 0xFFFAF0,             // rgb(255,250,240)
+  forest_green = 0x228B22,             // rgb(34,139,34)
+  fuchsia = 0xFF00FF,                  // rgb(255,0,255)
+  gainsboro = 0xDCDCDC,                // rgb(220,220,220)
+  ghost_white = 0xF8F8FF,              // rgb(248,248,255)
+  gold = 0xFFD700,                     // rgb(255,215,0)
+  golden_rod = 0xDAA520,               // rgb(218,165,32)
+  gray = 0x808080,                     // rgb(128,128,128)
+  green = 0x008000,                    // rgb(0,128,0)
+  green_yellow = 0xADFF2F,             // rgb(173,255,47)
+  honey_dew = 0xF0FFF0,                // rgb(240,255,240)
+  hot_pink = 0xFF69B4,                 // rgb(255,105,180)
+  indian_red = 0xCD5C5C,               // rgb(205,92,92)
+  indigo = 0x4B0082,                   // rgb(75,0,130)
+  ivory = 0xFFFFF0,                    // rgb(255,255,240)
+  khaki = 0xF0E68C,                    // rgb(240,230,140)
+  lavender = 0xE6E6FA,                 // rgb(230,230,250)
+  lavender_blush = 0xFFF0F5,           // rgb(255,240,245)
+  lawn_green = 0x7CFC00,               // rgb(124,252,0)
+  lemon_chiffon = 0xFFFACD,            // rgb(255,250,205)
+  light_blue = 0xADD8E6,               // rgb(173,216,230)
+  light_coral = 0xF08080,              // rgb(240,128,128)
+  light_cyan = 0xE0FFFF,               // rgb(224,255,255)
+  light_golden_rod_yellow = 0xFAFAD2,  // rgb(250,250,210)
+  light_gray = 0xD3D3D3,               // rgb(211,211,211)
+  light_green = 0x90EE90,              // rgb(144,238,144)
+  light_pink = 0xFFB6C1,               // rgb(255,182,193)
+  light_salmon = 0xFFA07A,             // rgb(255,160,122)
+  light_sea_green = 0x20B2AA,          // rgb(32,178,170)
+  light_sky_blue = 0x87CEFA,           // rgb(135,206,250)
+  light_slate_gray = 0x778899,         // rgb(119,136,153)
+  light_steel_blue = 0xB0C4DE,         // rgb(176,196,222)
+  light_yellow = 0xFFFFE0,             // rgb(255,255,224)
+  lime = 0x00FF00,                     // rgb(0,255,0)
+  lime_green = 0x32CD32,               // rgb(50,205,50)
+  linen = 0xFAF0E6,                    // rgb(250,240,230)
+  magenta = 0xFF00FF,                  // rgb(255,0,255)
+  maroon = 0x800000,                   // rgb(128,0,0)
+  medium_aquamarine = 0x66CDAA,        // rgb(102,205,170)
+  medium_blue = 0x0000CD,              // rgb(0,0,205)
+  medium_orchid = 0xBA55D3,            // rgb(186,85,211)
+  medium_purple = 0x9370DB,            // rgb(147,112,219)
+  medium_sea_green = 0x3CB371,         // rgb(60,179,113)
+  medium_slate_blue = 0x7B68EE,        // rgb(123,104,238)
+  medium_spring_green = 0x00FA9A,      // rgb(0,250,154)
+  medium_turquoise = 0x48D1CC,         // rgb(72,209,204)
+  medium_violet_red = 0xC71585,        // rgb(199,21,133)
+  midnight_blue = 0x191970,            // rgb(25,25,112)
+  mint_cream = 0xF5FFFA,               // rgb(245,255,250)
+  misty_rose = 0xFFE4E1,               // rgb(255,228,225)
+  moccasin = 0xFFE4B5,                 // rgb(255,228,181)
+  navajo_white = 0xFFDEAD,             // rgb(255,222,173)
+  navy = 0x000080,                     // rgb(0,0,128)
+  old_lace = 0xFDF5E6,                 // rgb(253,245,230)
+  olive = 0x808000,                    // rgb(128,128,0)
+  olive_drab = 0x6B8E23,               // rgb(107,142,35)
+  orange = 0xFFA500,                   // rgb(255,165,0)
+  orange_red = 0xFF4500,               // rgb(255,69,0)
+  orchid = 0xDA70D6,                   // rgb(218,112,214)
+  pale_golden_rod = 0xEEE8AA,          // rgb(238,232,170)
+  pale_green = 0x98FB98,               // rgb(152,251,152)
+  pale_turquoise = 0xAFEEEE,           // rgb(175,238,238)
+  pale_violet_red = 0xDB7093,          // rgb(219,112,147)
+  papaya_whip = 0xFFEFD5,              // rgb(255,239,213)
+  peach_puff = 0xFFDAB9,               // rgb(255,218,185)
+  peru = 0xCD853F,                     // rgb(205,133,63)
+  pink = 0xFFC0CB,                     // rgb(255,192,203)
+  plum = 0xDDA0DD,                     // rgb(221,160,221)
+  powder_blue = 0xB0E0E6,              // rgb(176,224,230)
+  purple = 0x800080,                   // rgb(128,0,128)
+  rebecca_purple = 0x663399,           // rgb(102,51,153)
+  red = 0xFF0000,                      // rgb(255,0,0)
+  rosy_brown = 0xBC8F8F,               // rgb(188,143,143)
+  royal_blue = 0x4169E1,               // rgb(65,105,225)
+  saddle_brown = 0x8B4513,             // rgb(139,69,19)
+  salmon = 0xFA8072,                   // rgb(250,128,114)
+  sandy_brown = 0xF4A460,              // rgb(244,164,96)
+  sea_green = 0x2E8B57,                // rgb(46,139,87)
+  sea_shell = 0xFFF5EE,                // rgb(255,245,238)
+  sienna = 0xA0522D,                   // rgb(160,82,45)
+  silver = 0xC0C0C0,                   // rgb(192,192,192)
+  sky_blue = 0x87CEEB,                 // rgb(135,206,235)
+  slate_blue = 0x6A5ACD,               // rgb(106,90,205)
+  slate_gray = 0x708090,               // rgb(112,128,144)
+  snow = 0xFFFAFA,                     // rgb(255,250,250)
+  spring_green = 0x00FF7F,             // rgb(0,255,127)
+  steel_blue = 0x4682B4,               // rgb(70,130,180)
+  tan = 0xD2B48C,                      // rgb(210,180,140)
+  teal = 0x008080,                     // rgb(0,128,128)
+  thistle = 0xD8BFD8,                  // rgb(216,191,216)
+  tomato = 0xFF6347,                   // rgb(255,99,71)
+  turquoise = 0x40E0D0,                // rgb(64,224,208)
+  violet = 0xEE82EE,                   // rgb(238,130,238)
+  wheat = 0xF5DEB3,                    // rgb(245,222,179)
+  white = 0xFFFFFF,                    // rgb(255,255,255)
+  white_smoke = 0xF5F5F5,              // rgb(245,245,245)
+  yellow = 0xFFFF00,                   // rgb(255,255,0)
+  yellow_green = 0x9ACD32              // rgb(154,205,50)
+};                                     // enum class color
+
+enum class terminal_color : uint8_t {
+  black = 30,
+  red,
+  green,
+  yellow,
+  blue,
+  magenta,
+  cyan,
+  white,
+  bright_black = 90,
+  bright_red,
+  bright_green,
+  bright_yellow,
+  bright_blue,
+  bright_magenta,
+  bright_cyan,
+  bright_white
+};
+
+enum class emphasis : uint8_t {
+  bold = 1,
+  faint = 1 << 1,
+  italic = 1 << 2,
+  underline = 1 << 3,
+  blink = 1 << 4,
+  reverse = 1 << 5,
+  conceal = 1 << 6,
+  strikethrough = 1 << 7,
+};
+
+// rgb is a struct for red, green and blue colors.
+// Using the name "rgb" makes some editors show the color in a tooltip.
+struct rgb {
+  FMT_CONSTEXPR rgb() : r(0), g(0), b(0) {}
+  FMT_CONSTEXPR rgb(uint8_t r_, uint8_t g_, uint8_t b_) : r(r_), g(g_), b(b_) {}
+  FMT_CONSTEXPR rgb(uint32_t hex)
+      : r((hex >> 16) & 0xFF), g((hex >> 8) & 0xFF), b(hex & 0xFF) {}
+  FMT_CONSTEXPR rgb(color hex)
+      : r((uint32_t(hex) >> 16) & 0xFF),
+        g((uint32_t(hex) >> 8) & 0xFF),
+        b(uint32_t(hex) & 0xFF) {}
+  uint8_t r;
+  uint8_t g;
+  uint8_t b;
+};
+
+namespace detail {
+
+// color is a struct of either a rgb color or a terminal color.
+struct color_type {
+  FMT_CONSTEXPR color_type() noexcept : is_rgb(), value{} {}
+  FMT_CONSTEXPR color_type(color rgb_color) noexcept : is_rgb(true), value{} {
+    value.rgb_color = static_cast<uint32_t>(rgb_color);
+  }
+  FMT_CONSTEXPR color_type(rgb rgb_color) noexcept : is_rgb(true), value{} {
+    value.rgb_color = (static_cast<uint32_t>(rgb_color.r) << 16) |
+                      (static_cast<uint32_t>(rgb_color.g) << 8) | rgb_color.b;
+  }
+  FMT_CONSTEXPR color_type(terminal_color term_color) noexcept
+      : is_rgb(), value{} {
+    value.term_color = static_cast<uint8_t>(term_color);
+  }
+  bool is_rgb;
+  union color_union {
+    uint8_t term_color;
+    uint32_t rgb_color;
+  } value;
+};
+}  // namespace detail
+
+/// A text style consisting of foreground and background colors and emphasis.
+class text_style {
+ public:
+  FMT_CONSTEXPR text_style(emphasis em = emphasis()) noexcept
+      : set_foreground_color(), set_background_color(), ems(em) {}
+
+  FMT_CONSTEXPR auto operator|=(const text_style& rhs) -> text_style& {
+    if (!set_foreground_color) {
+      set_foreground_color = rhs.set_foreground_color;
+      foreground_color = rhs.foreground_color;
+    } else if (rhs.set_foreground_color) {
+      if (!foreground_color.is_rgb || !rhs.foreground_color.is_rgb)
+        report_error("can't OR a terminal color");
+      foreground_color.value.rgb_color |= rhs.foreground_color.value.rgb_color;
+    }
+
+    if (!set_background_color) {
+      set_background_color = rhs.set_background_color;
+      background_color = rhs.background_color;
+    } else if (rhs.set_background_color) {
+      if (!background_color.is_rgb || !rhs.background_color.is_rgb)
+        report_error("can't OR a terminal color");
+      background_color.value.rgb_color |= rhs.background_color.value.rgb_color;
+    }
+
+    ems = static_cast<emphasis>(static_cast<uint8_t>(ems) |
+                                static_cast<uint8_t>(rhs.ems));
+    return *this;
+  }
+
+  friend FMT_CONSTEXPR auto operator|(text_style lhs, const text_style& rhs)
+      -> text_style {
+    return lhs |= rhs;
+  }
+
+  FMT_CONSTEXPR auto has_foreground() const noexcept -> bool {
+    return set_foreground_color;
+  }
+  FMT_CONSTEXPR auto has_background() const noexcept -> bool {
+    return set_background_color;
+  }
+  FMT_CONSTEXPR auto has_emphasis() const noexcept -> bool {
+    return static_cast<uint8_t>(ems) != 0;
+  }
+  FMT_CONSTEXPR auto get_foreground() const noexcept -> detail::color_type {
+    FMT_ASSERT(has_foreground(), "no foreground specified for this style");
+    return foreground_color;
+  }
+  FMT_CONSTEXPR auto get_background() const noexcept -> detail::color_type {
+    FMT_ASSERT(has_background(), "no background specified for this style");
+    return background_color;
+  }
+  FMT_CONSTEXPR auto get_emphasis() const noexcept -> emphasis {
+    FMT_ASSERT(has_emphasis(), "no emphasis specified for this style");
+    return ems;
+  }
+
+ private:
+  FMT_CONSTEXPR text_style(bool is_foreground,
+                           detail::color_type text_color) noexcept
+      : set_foreground_color(), set_background_color(), ems() {
+    if (is_foreground) {
+      foreground_color = text_color;
+      set_foreground_color = true;
+    } else {
+      background_color = text_color;
+      set_background_color = true;
+    }
+  }
+
+  friend FMT_CONSTEXPR auto fg(detail::color_type foreground) noexcept
+      -> text_style;
+
+  friend FMT_CONSTEXPR auto bg(detail::color_type background) noexcept
+      -> text_style;
+
+  detail::color_type foreground_color;
+  detail::color_type background_color;
+  bool set_foreground_color;
+  bool set_background_color;
+  emphasis ems;
+};
+
+/// Creates a text style from the foreground (text) color.
+FMT_CONSTEXPR inline auto fg(detail::color_type foreground) noexcept
+    -> text_style {
+  return text_style(true, foreground);
+}
+
+/// Creates a text style from the background color.
+FMT_CONSTEXPR inline auto bg(detail::color_type background) noexcept
+    -> text_style {
+  return text_style(false, background);
+}
+
+FMT_CONSTEXPR inline auto operator|(emphasis lhs, emphasis rhs) noexcept
+    -> text_style {
+  return text_style(lhs) | rhs;
+}
+
+namespace detail {
+
+template <typename Char> struct ansi_color_escape {
+  FMT_CONSTEXPR ansi_color_escape(color_type text_color,
+                                  const char* esc) noexcept {
+    // If we have a terminal color, we need to output another escape code
+    // sequence.
+    if (!text_color.is_rgb) {
+      bool is_background = esc == string_view("\x1b[48;2;");
+      uint32_t value = text_color.value.term_color;
+      // Background ASCII codes are the same as the foreground ones but with
+      // 10 more.
+      if (is_background) value += 10u;
+
+      size_t index = 0;
+      buffer[index++] = static_cast<Char>('\x1b');
+      buffer[index++] = static_cast<Char>('[');
+
+      if (value >= 100u) {
+        buffer[index++] = static_cast<Char>('1');
+        value %= 100u;
+      }
+      buffer[index++] = static_cast<Char>('0' + value / 10u);
+      buffer[index++] = static_cast<Char>('0' + value % 10u);
+
+      buffer[index++] = static_cast<Char>('m');
+      buffer[index++] = static_cast<Char>('\0');
+      return;
+    }
+
+    for (int i = 0; i < 7; i++) {
+      buffer[i] = static_cast<Char>(esc[i]);
+    }
+    rgb color(text_color.value.rgb_color);
+    to_esc(color.r, buffer + 7, ';');
+    to_esc(color.g, buffer + 11, ';');
+    to_esc(color.b, buffer + 15, 'm');
+    buffer[19] = static_cast<Char>(0);
+  }
+  FMT_CONSTEXPR ansi_color_escape(emphasis em) noexcept {
+    uint8_t em_codes[num_emphases] = {};
+    if (has_emphasis(em, emphasis::bold)) em_codes[0] = 1;
+    if (has_emphasis(em, emphasis::faint)) em_codes[1] = 2;
+    if (has_emphasis(em, emphasis::italic)) em_codes[2] = 3;
+    if (has_emphasis(em, emphasis::underline)) em_codes[3] = 4;
+    if (has_emphasis(em, emphasis::blink)) em_codes[4] = 5;
+    if (has_emphasis(em, emphasis::reverse)) em_codes[5] = 7;
+    if (has_emphasis(em, emphasis::conceal)) em_codes[6] = 8;
+    if (has_emphasis(em, emphasis::strikethrough)) em_codes[7] = 9;
+
+    size_t index = 0;
+    for (size_t i = 0; i < num_emphases; ++i) {
+      if (!em_codes[i]) continue;
+      buffer[index++] = static_cast<Char>('\x1b');
+      buffer[index++] = static_cast<Char>('[');
+      buffer[index++] = static_cast<Char>('0' + em_codes[i]);
+      buffer[index++] = static_cast<Char>('m');
+    }
+    buffer[index++] = static_cast<Char>(0);
+  }
+  FMT_CONSTEXPR operator const Char*() const noexcept { return buffer; }
+
+  FMT_CONSTEXPR auto begin() const noexcept -> const Char* { return buffer; }
+  FMT_CONSTEXPR20 auto end() const noexcept -> const Char* {
+    return buffer + basic_string_view<Char>(buffer).size();
+  }
+
+ private:
+  static constexpr size_t num_emphases = 8;
+  Char buffer[7u + 3u * num_emphases + 1u];
+
+  static FMT_CONSTEXPR void to_esc(uint8_t c, Char* out,
+                                   char delimiter) noexcept {
+    out[0] = static_cast<Char>('0' + c / 100);
+    out[1] = static_cast<Char>('0' + c / 10 % 10);
+    out[2] = static_cast<Char>('0' + c % 10);
+    out[3] = static_cast<Char>(delimiter);
+  }
+  static FMT_CONSTEXPR auto has_emphasis(emphasis em, emphasis mask) noexcept
+      -> bool {
+    return static_cast<uint8_t>(em) & static_cast<uint8_t>(mask);
+  }
+};
+
+template <typename Char>
+FMT_CONSTEXPR auto make_foreground_color(color_type foreground) noexcept
+    -> ansi_color_escape<Char> {
+  return ansi_color_escape<Char>(foreground, "\x1b[38;2;");
+}
+
+template <typename Char>
+FMT_CONSTEXPR auto make_background_color(color_type background) noexcept
+    -> ansi_color_escape<Char> {
+  return ansi_color_escape<Char>(background, "\x1b[48;2;");
+}
+
+template <typename Char>
+FMT_CONSTEXPR auto make_emphasis(emphasis em) noexcept
+    -> ansi_color_escape<Char> {
+  return ansi_color_escape<Char>(em);
+}
+
+template <typename Char> inline void reset_color(buffer<Char>& buffer) {
+  auto reset_color = string_view("\x1b[0m");
+  buffer.append(reset_color.begin(), reset_color.end());
+}
+
+template <typename T> struct styled_arg : view {
+  const T& value;
+  text_style style;
+  styled_arg(const T& v, text_style s) : value(v), style(s) {}
+};
+
+template <typename Char>
+void vformat_to(buffer<Char>& buf, const text_style& ts,
+                basic_string_view<Char> fmt,
+                basic_format_args<buffered_context<Char>> args) {
+  bool has_style = false;
+  if (ts.has_emphasis()) {
+    has_style = true;
+    auto emphasis = make_emphasis<Char>(ts.get_emphasis());
+    buf.append(emphasis.begin(), emphasis.end());
+  }
+  if (ts.has_foreground()) {
+    has_style = true;
+    auto foreground = make_foreground_color<Char>(ts.get_foreground());
+    buf.append(foreground.begin(), foreground.end());
+  }
+  if (ts.has_background()) {
+    has_style = true;
+    auto background = make_background_color<Char>(ts.get_background());
+    buf.append(background.begin(), background.end());
+  }
+  vformat_to(buf, fmt, args);
+  if (has_style) reset_color<Char>(buf);
+}
+}  // namespace detail
+
+inline void vprint(FILE* f, const text_style& ts, string_view fmt,
+                   format_args args) {
+  auto buf = memory_buffer();
+  detail::vformat_to(buf, ts, fmt, args);
+  print(f, FMT_STRING("{}"), string_view(buf.begin(), buf.size()));
+}
+
+/**
+ * Formats a string and prints it to the specified file stream using ANSI
+ * escape sequences to specify text formatting.
+ *
+ * **Example**:
+ *
+ *     fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
+ *                "Elapsed time: {0:.2f} seconds", 1.23);
+ */
+template <typename... T>
+void print(FILE* f, const text_style& ts, format_string<T...> fmt,
+           T&&... args) {
+  vprint(f, ts, fmt.str, vargs<T...>{{args...}});
+}
+
+/**
+ * Formats a string and prints it to stdout using ANSI escape sequences to
+ * specify text formatting.
+ *
+ * **Example**:
+ *
+ *     fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
+ *                "Elapsed time: {0:.2f} seconds", 1.23);
+ */
+template <typename... T>
+void print(const text_style& ts, format_string<T...> fmt, T&&... args) {
+  return print(stdout, ts, fmt, std::forward<T>(args)...);
+}
+
+inline auto vformat(const text_style& ts, string_view fmt, format_args args)
+    -> std::string {
+  auto buf = memory_buffer();
+  detail::vformat_to(buf, ts, fmt, args);
+  return fmt::to_string(buf);
+}
+
+/**
+ * Formats arguments and returns the result as a string using ANSI escape
+ * sequences to specify text formatting.
+ *
+ * **Example**:
+ *
+ * ```
+ * #include <fmt/color.h>
+ * std::string message = fmt::format(fmt::emphasis::bold | fg(fmt::color::red),
+ *                                   "The answer is {}", 42);
+ * ```
+ */
+template <typename... T>
+inline auto format(const text_style& ts, format_string<T...> fmt, T&&... args)
+    -> std::string {
+  return fmt::vformat(ts, fmt.str, vargs<T...>{{args...}});
+}
+
+/// Formats a string with the given text_style and writes the output to `out`.
+template <typename OutputIt,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, char>::value)>
+auto vformat_to(OutputIt out, const text_style& ts, string_view fmt,
+                format_args args) -> OutputIt {
+  auto&& buf = detail::get_buffer<char>(out);
+  detail::vformat_to(buf, ts, fmt, args);
+  return detail::get_iterator(buf, out);
+}
+
+/**
+ * Formats arguments with the given text style, writes the result to the output
+ * iterator `out` and returns the iterator past the end of the output range.
+ *
+ * **Example**:
+ *
+ *     std::vector<char> out;
+ *     fmt::format_to(std::back_inserter(out),
+ *                    fmt::emphasis::bold | fg(fmt::color::red), "{}", 42);
+ */
+template <typename OutputIt, typename... T,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, char>::value)>
+inline auto format_to(OutputIt out, const text_style& ts,
+                      format_string<T...> fmt, T&&... args) -> OutputIt {
+  return vformat_to(out, ts, fmt.str, vargs<T...>{{args...}});
+}
+
+template <typename T, typename Char>
+struct formatter<detail::styled_arg<T>, Char> : formatter<T, Char> {
+  template <typename FormatContext>
+  auto format(const detail::styled_arg<T>& arg, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    const auto& ts = arg.style;
+    auto out = ctx.out();
+
+    bool has_style = false;
+    if (ts.has_emphasis()) {
+      has_style = true;
+      auto emphasis = detail::make_emphasis<Char>(ts.get_emphasis());
+      out = detail::copy<Char>(emphasis.begin(), emphasis.end(), out);
+    }
+    if (ts.has_foreground()) {
+      has_style = true;
+      auto foreground =
+          detail::make_foreground_color<Char>(ts.get_foreground());
+      out = detail::copy<Char>(foreground.begin(), foreground.end(), out);
+    }
+    if (ts.has_background()) {
+      has_style = true;
+      auto background =
+          detail::make_background_color<Char>(ts.get_background());
+      out = detail::copy<Char>(background.begin(), background.end(), out);
+    }
+    out = formatter<T, Char>::format(arg.value, ctx);
+    if (has_style) {
+      auto reset_color = string_view("\x1b[0m");
+      out = detail::copy<Char>(reset_color.begin(), reset_color.end(), out);
+    }
+    return out;
+  }
+};
+
+/**
+ * Returns an argument that will be formatted using ANSI escape sequences,
+ * to be used in a formatting function.
+ *
+ * **Example**:
+ *
+ *     fmt::print("Elapsed time: {0:.2f} seconds",
+ *                fmt::styled(1.23, fmt::fg(fmt::color::green) |
+ *                                  fmt::bg(fmt::color::blue)));
+ */
+template <typename T>
+FMT_CONSTEXPR auto styled(const T& value, text_style ts)
+    -> detail::styled_arg<remove_cvref_t<T>> {
+  return detail::styled_arg<remove_cvref_t<T>>{value, ts};
+}
+
+FMT_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_COLOR_H_

extlib/libfmt/include/fmt/compile.h

@@ -0,0 +1,551 @@
+// Formatting library for C++ - experimental format string compilation
+//
+// Copyright (c) 2012 - present, Victor Zverovich and fmt contributors
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_COMPILE_H_
+#define FMT_COMPILE_H_
+
+#ifndef FMT_MODULE
+#  include <iterator>  // std::back_inserter
+#endif
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+
+// A compile-time string which is compiled into fast formatting code.
+FMT_EXPORT class compiled_string {};
+
+namespace detail {
+
+template <typename S>
+struct is_compiled_string : std::is_base_of<compiled_string, S> {};
+
+/**
+ * Converts a string literal `s` into a format string that will be parsed at
+ * compile time and converted into efficient formatting code. Requires C++17
+ * `constexpr if` compiler support.
+ *
+ * **Example**:
+ *
+ *     // Converts 42 into std::string using the most efficient method and no
+ *     // runtime format string processing.
+ *     std::string s = fmt::format(FMT_COMPILE("{}"), 42);
+ */
+#if defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+#  define FMT_COMPILE(s) FMT_STRING_IMPL(s, fmt::compiled_string)
+#else
+#  define FMT_COMPILE(s) FMT_STRING(s)
+#endif
+
+#if FMT_USE_NONTYPE_TEMPLATE_ARGS
+template <typename Char, size_t N, fmt::detail::fixed_string<Char, N> Str>
+struct udl_compiled_string : compiled_string {
+  using char_type = Char;
+  constexpr explicit operator basic_string_view<char_type>() const {
+    return {Str.data, N - 1};
+  }
+};
+#endif
+
+template <typename T, typename... Tail>
+auto first(const T& value, const Tail&...) -> const T& {
+  return value;
+}
+
+#if defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+template <typename... Args> struct type_list {};
+
+// Returns a reference to the argument at index N from [first, rest...].
+template <int N, typename T, typename... Args>
+constexpr const auto& get([[maybe_unused]] const T& first,
+                          [[maybe_unused]] const Args&... rest) {
+  static_assert(N < 1 + sizeof...(Args), "index is out of bounds");
+  if constexpr (N == 0)
+    return first;
+  else
+    return detail::get<N - 1>(rest...);
+}
+
+#  if FMT_USE_NONTYPE_TEMPLATE_ARGS
+template <int N, typename T, typename... Args, typename Char>
+constexpr auto get_arg_index_by_name(basic_string_view<Char> name) -> int {
+  if constexpr (is_static_named_arg<T>()) {
+    if (name == T::name) return N;
+  }
+  if constexpr (sizeof...(Args) > 0)
+    return get_arg_index_by_name<N + 1, Args...>(name);
+  (void)name;  // Workaround an MSVC bug about "unused" parameter.
+  return -1;
+}
+#  endif
+
+template <typename... Args, typename Char>
+FMT_CONSTEXPR auto get_arg_index_by_name(basic_string_view<Char> name) -> int {
+#  if FMT_USE_NONTYPE_TEMPLATE_ARGS
+  if constexpr (sizeof...(Args) > 0)
+    return get_arg_index_by_name<0, Args...>(name);
+#  endif
+  (void)name;
+  return -1;
+}
+
+template <typename Char, typename... Args>
+constexpr int get_arg_index_by_name(basic_string_view<Char> name,
+                                    type_list<Args...>) {
+  return get_arg_index_by_name<Args...>(name);
+}
+
+template <int N, typename> struct get_type_impl;
+
+template <int N, typename... Args> struct get_type_impl<N, type_list<Args...>> {
+  using type =
+      remove_cvref_t<decltype(detail::get<N>(std::declval<Args>()...))>;
+};
+
+template <int N, typename T>
+using get_type = typename get_type_impl<N, T>::type;
+
+template <typename T> struct is_compiled_format : std::false_type {};
+
+template <typename Char> struct text {
+  basic_string_view<Char> data;
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&...) const {
+    return write<Char>(out, data);
+  }
+};
+
+template <typename Char>
+struct is_compiled_format<text<Char>> : std::true_type {};
+
+template <typename Char>
+constexpr text<Char> make_text(basic_string_view<Char> s, size_t pos,
+                               size_t size) {
+  return {{&s[pos], size}};
+}
+
+template <typename Char> struct code_unit {
+  Char value;
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&...) const {
+    *out++ = value;
+    return out;
+  }
+};
+
+// This ensures that the argument type is convertible to `const T&`.
+template <typename T, int N, typename... Args>
+constexpr const T& get_arg_checked(const Args&... args) {
+  const auto& arg = detail::get<N>(args...);
+  if constexpr (detail::is_named_arg<remove_cvref_t<decltype(arg)>>()) {
+    return arg.value;
+  } else {
+    return arg;
+  }
+}
+
+template <typename Char>
+struct is_compiled_format<code_unit<Char>> : std::true_type {};
+
+// A replacement field that refers to argument N.
+template <typename Char, typename T, int N> struct field {
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&... args) const {
+    const T& arg = get_arg_checked<T, N>(args...);
+    if constexpr (std::is_convertible<T, basic_string_view<Char>>::value) {
+      auto s = basic_string_view<Char>(arg);
+      return copy<Char>(s.begin(), s.end(), out);
+    } else {
+      return write<Char>(out, arg);
+    }
+  }
+};
+
+template <typename Char, typename T, int N>
+struct is_compiled_format<field<Char, T, N>> : std::true_type {};
+
+// A replacement field that refers to argument with name.
+template <typename Char> struct runtime_named_field {
+  using char_type = Char;
+  basic_string_view<Char> name;
+
+  template <typename OutputIt, typename T>
+  constexpr static bool try_format_argument(
+      OutputIt& out,
+      // [[maybe_unused]] due to unused-but-set-parameter warning in GCC 7,8,9
+      [[maybe_unused]] basic_string_view<Char> arg_name, const T& arg) {
+    if constexpr (is_named_arg<typename std::remove_cv<T>::type>::value) {
+      if (arg_name == arg.name) {
+        out = write<Char>(out, arg.value);
+        return true;
+      }
+    }
+    return false;
+  }
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&... args) const {
+    bool found = (try_format_argument(out, name, args) || ...);
+    if (!found) {
+      FMT_THROW(format_error("argument with specified name is not found"));
+    }
+    return out;
+  }
+};
+
+template <typename Char>
+struct is_compiled_format<runtime_named_field<Char>> : std::true_type {};
+
+// A replacement field that refers to argument N and has format specifiers.
+template <typename Char, typename T, int N> struct spec_field {
+  using char_type = Char;
+  formatter<T, Char> fmt;
+
+  template <typename OutputIt, typename... Args>
+  constexpr FMT_INLINE OutputIt format(OutputIt out,
+                                       const Args&... args) const {
+    const auto& vargs =
+        fmt::make_format_args<basic_format_context<OutputIt, Char>>(args...);
+    basic_format_context<OutputIt, Char> ctx(out, vargs);
+    return fmt.format(get_arg_checked<T, N>(args...), ctx);
+  }
+};
+
+template <typename Char, typename T, int N>
+struct is_compiled_format<spec_field<Char, T, N>> : std::true_type {};
+
+template <typename L, typename R> struct concat {
+  L lhs;
+  R rhs;
+  using char_type = typename L::char_type;
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&... args) const {
+    out = lhs.format(out, args...);
+    return rhs.format(out, args...);
+  }
+};
+
+template <typename L, typename R>
+struct is_compiled_format<concat<L, R>> : std::true_type {};
+
+template <typename L, typename R>
+constexpr concat<L, R> make_concat(L lhs, R rhs) {
+  return {lhs, rhs};
+}
+
+struct unknown_format {};
+
+template <typename Char>
+constexpr size_t parse_text(basic_string_view<Char> str, size_t pos) {
+  for (size_t size = str.size(); pos != size; ++pos) {
+    if (str[pos] == '{' || str[pos] == '}') break;
+  }
+  return pos;
+}
+
+template <typename Args, size_t POS, int ID, typename S>
+constexpr auto compile_format_string(S fmt);
+
+template <typename Args, size_t POS, int ID, typename T, typename S>
+constexpr auto parse_tail(T head, S fmt) {
+  if constexpr (POS != basic_string_view<typename S::char_type>(fmt).size()) {
+    constexpr auto tail = compile_format_string<Args, POS, ID>(fmt);
+    if constexpr (std::is_same<remove_cvref_t<decltype(tail)>,
+                               unknown_format>())
+      return tail;
+    else
+      return make_concat(head, tail);
+  } else {
+    return head;
+  }
+}
+
+template <typename T, typename Char> struct parse_specs_result {
+  formatter<T, Char> fmt;
+  size_t end;
+  int next_arg_id;
+};
+
+enum { manual_indexing_id = -1 };
+
+template <typename T, typename Char>
+constexpr parse_specs_result<T, Char> parse_specs(basic_string_view<Char> str,
+                                                  size_t pos, int next_arg_id) {
+  str.remove_prefix(pos);
+  auto ctx =
+      compile_parse_context<Char>(str, max_value<int>(), nullptr, next_arg_id);
+  auto f = formatter<T, Char>();
+  auto end = f.parse(ctx);
+  return {f, pos + fmt::detail::to_unsigned(end - str.data()),
+          next_arg_id == 0 ? manual_indexing_id : ctx.next_arg_id()};
+}
+
+template <typename Char> struct arg_id_handler {
+  arg_id_kind kind;
+  arg_ref<Char> arg_id;
+
+  constexpr int on_auto() {
+    FMT_ASSERT(false, "handler cannot be used with automatic indexing");
+    return 0;
+  }
+  constexpr int on_index(int id) {
+    kind = arg_id_kind::index;
+    arg_id = arg_ref<Char>(id);
+    return 0;
+  }
+  constexpr int on_name(basic_string_view<Char> id) {
+    kind = arg_id_kind::name;
+    arg_id = arg_ref<Char>(id);
+    return 0;
+  }
+};
+
+template <typename Char> struct parse_arg_id_result {
+  arg_id_kind kind;
+  arg_ref<Char> arg_id;
+  const Char* arg_id_end;
+};
+
+template <int ID, typename Char>
+constexpr auto parse_arg_id(const Char* begin, const Char* end) {
+  auto handler = arg_id_handler<Char>{arg_id_kind::none, arg_ref<Char>{}};
+  auto arg_id_end = parse_arg_id(begin, end, handler);
+  return parse_arg_id_result<Char>{handler.kind, handler.arg_id, arg_id_end};
+}
+
+template <typename T, typename Enable = void> struct field_type {
+  using type = remove_cvref_t<T>;
+};
+
+template <typename T>
+struct field_type<T, enable_if_t<detail::is_named_arg<T>::value>> {
+  using type = remove_cvref_t<decltype(T::value)>;
+};
+
+template <typename T, typename Args, size_t END_POS, int ARG_INDEX, int NEXT_ID,
+          typename S>
+constexpr auto parse_replacement_field_then_tail(S fmt) {
+  using char_type = typename S::char_type;
+  constexpr auto str = basic_string_view<char_type>(fmt);
+  constexpr char_type c = END_POS != str.size() ? str[END_POS] : char_type();
+  if constexpr (c == '}') {
+    return parse_tail<Args, END_POS + 1, NEXT_ID>(
+        field<char_type, typename field_type<T>::type, ARG_INDEX>(), fmt);
+  } else if constexpr (c != ':') {
+    FMT_THROW(format_error("expected ':'"));
+  } else {
+    constexpr auto result = parse_specs<typename field_type<T>::type>(
+        str, END_POS + 1, NEXT_ID == manual_indexing_id ? 0 : NEXT_ID);
+    if constexpr (result.end >= str.size() || str[result.end] != '}') {
+      FMT_THROW(format_error("expected '}'"));
+      return 0;
+    } else {
+      return parse_tail<Args, result.end + 1, result.next_arg_id>(
+          spec_field<char_type, typename field_type<T>::type, ARG_INDEX>{
+              result.fmt},
+          fmt);
+    }
+  }
+}
+
+// Compiles a non-empty format string and returns the compiled representation
+// or unknown_format() on unrecognized input.
+template <typename Args, size_t POS, int ID, typename S>
+constexpr auto compile_format_string(S fmt) {
+  using char_type = typename S::char_type;
+  constexpr auto str = basic_string_view<char_type>(fmt);
+  if constexpr (str[POS] == '{') {
+    if constexpr (POS + 1 == str.size())
+      FMT_THROW(format_error("unmatched '{' in format string"));
+    if constexpr (str[POS + 1] == '{') {
+      return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), fmt);
+    } else if constexpr (str[POS + 1] == '}' || str[POS + 1] == ':') {
+      static_assert(ID != manual_indexing_id,
+                    "cannot switch from manual to automatic argument indexing");
+      constexpr auto next_id =
+          ID != manual_indexing_id ? ID + 1 : manual_indexing_id;
+      return parse_replacement_field_then_tail<get_type<ID, Args>, Args,
+                                               POS + 1, ID, next_id>(fmt);
+    } else {
+      constexpr auto arg_id_result =
+          parse_arg_id<ID>(str.data() + POS + 1, str.data() + str.size());
+      constexpr auto arg_id_end_pos = arg_id_result.arg_id_end - str.data();
+      constexpr char_type c =
+          arg_id_end_pos != str.size() ? str[arg_id_end_pos] : char_type();
+      static_assert(c == '}' || c == ':', "missing '}' in format string");
+      if constexpr (arg_id_result.kind == arg_id_kind::index) {
+        static_assert(
+            ID == manual_indexing_id || ID == 0,
+            "cannot switch from automatic to manual argument indexing");
+        constexpr auto arg_index = arg_id_result.arg_id.index;
+        return parse_replacement_field_then_tail<get_type<arg_index, Args>,
+                                                 Args, arg_id_end_pos,
+                                                 arg_index, manual_indexing_id>(
+            fmt);
+      } else if constexpr (arg_id_result.kind == arg_id_kind::name) {
+        constexpr auto arg_index =
+            get_arg_index_by_name(arg_id_result.arg_id.name, Args{});
+        if constexpr (arg_index >= 0) {
+          constexpr auto next_id =
+              ID != manual_indexing_id ? ID + 1 : manual_indexing_id;
+          return parse_replacement_field_then_tail<
+              decltype(get_type<arg_index, Args>::value), Args, arg_id_end_pos,
+              arg_index, next_id>(fmt);
+        } else if constexpr (c == '}') {
+          return parse_tail<Args, arg_id_end_pos + 1, ID>(
+              runtime_named_field<char_type>{arg_id_result.arg_id.name}, fmt);
+        } else if constexpr (c == ':') {
+          return unknown_format();  // no type info for specs parsing
+        }
+      }
+    }
+  } else if constexpr (str[POS] == '}') {
+    if constexpr (POS + 1 == str.size())
+      FMT_THROW(format_error("unmatched '}' in format string"));
+    return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), fmt);
+  } else {
+    constexpr auto end = parse_text(str, POS + 1);
+    if constexpr (end - POS > 1) {
+      return parse_tail<Args, end, ID>(make_text(str, POS, end - POS), fmt);
+    } else {
+      return parse_tail<Args, end, ID>(code_unit<char_type>{str[POS]}, fmt);
+    }
+  }
+}
+
+template <typename... Args, typename S,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+constexpr auto compile(S fmt) {
+  constexpr auto str = basic_string_view<typename S::char_type>(fmt);
+  if constexpr (str.size() == 0) {
+    return detail::make_text(str, 0, 0);
+  } else {
+    constexpr auto result =
+        detail::compile_format_string<detail::type_list<Args...>, 0, 0>(fmt);
+    return result;
+  }
+}
+#endif  // defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+}  // namespace detail
+
+FMT_BEGIN_EXPORT
+
+#if defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+
+template <typename CompiledFormat, typename... Args,
+          typename Char = typename CompiledFormat::char_type,
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+FMT_INLINE std::basic_string<Char> format(const CompiledFormat& cf,
+                                          const Args&... args) {
+  auto s = std::basic_string<Char>();
+  cf.format(std::back_inserter(s), args...);
+  return s;
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+constexpr FMT_INLINE OutputIt format_to(OutputIt out, const CompiledFormat& cf,
+                                        const Args&... args) {
+  return cf.format(out, args...);
+}
+
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+FMT_INLINE std::basic_string<typename S::char_type> format(const S&,
+                                                           Args&&... args) {
+  if constexpr (std::is_same<typename S::char_type, char>::value) {
+    constexpr auto str = basic_string_view<typename S::char_type>(S());
+    if constexpr (str.size() == 2 && str[0] == '{' && str[1] == '}') {
+      const auto& first = detail::first(args...);
+      if constexpr (detail::is_named_arg<
+                        remove_cvref_t<decltype(first)>>::value) {
+        return fmt::to_string(first.value);
+      } else {
+        return fmt::to_string(first);
+      }
+    }
+  }
+  constexpr auto compiled = detail::compile<Args...>(S());
+  if constexpr (std::is_same<remove_cvref_t<decltype(compiled)>,
+                             detail::unknown_format>()) {
+    return fmt::format(
+        static_cast<basic_string_view<typename S::char_type>>(S()),
+        std::forward<Args>(args)...);
+  } else {
+    return fmt::format(compiled, std::forward<Args>(args)...);
+  }
+}
+
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+FMT_CONSTEXPR OutputIt format_to(OutputIt out, const S&, Args&&... args) {
+  constexpr auto compiled = detail::compile<Args...>(S());
+  if constexpr (std::is_same<remove_cvref_t<decltype(compiled)>,
+                             detail::unknown_format>()) {
+    return fmt::format_to(
+        out, static_cast<basic_string_view<typename S::char_type>>(S()),
+        std::forward<Args>(args)...);
+  } else {
+    return fmt::format_to(out, compiled, std::forward<Args>(args)...);
+  }
+}
+#endif
+
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+auto format_to_n(OutputIt out, size_t n, const S& fmt, Args&&... args)
+    -> format_to_n_result<OutputIt> {
+  using traits = detail::fixed_buffer_traits;
+  auto buf = detail::iterator_buffer<OutputIt, char, traits>(out, n);
+  fmt::format_to(std::back_inserter(buf), fmt, std::forward<Args>(args)...);
+  return {buf.out(), buf.count()};
+}
+
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+FMT_CONSTEXPR20 auto formatted_size(const S& fmt, const Args&... args)
+    -> size_t {
+  auto buf = detail::counting_buffer<>();
+  fmt::format_to(appender(buf), fmt, args...);
+  return buf.count();
+}
+
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+void print(std::FILE* f, const S& fmt, const Args&... args) {
+  auto buf = memory_buffer();
+  fmt::format_to(appender(buf), fmt, args...);
+  detail::print(f, {buf.data(), buf.size()});
+}
+
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+void print(const S& fmt, const Args&... args) {
+  print(stdout, fmt, args...);
+}
+
+#if FMT_USE_NONTYPE_TEMPLATE_ARGS
+inline namespace literals {
+template <detail::fixed_string Str> constexpr auto operator""_cf() {
+  using char_t = remove_cvref_t<decltype(Str.data[0])>;
+  return detail::udl_compiled_string<char_t, sizeof(Str.data) / sizeof(char_t),
+                                     Str>();
+}
+}  // namespace literals
+#endif
+
+FMT_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_COMPILE_H_

extlib/libfmt/include/fmt/core.h

@@ -0,0 +1,5 @@
+// This file is only provided for compatibility and may be removed in future
+// versions. Use fmt/base.h if you don't need fmt::format and fmt/format.h
+// otherwise.
+
+#include "format.h"

extlib/libfmt/include/fmt/os.h

@@ -0,0 +1,427 @@
+// Formatting library for C++ - optional OS-specific functionality
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_OS_H_
+#define FMT_OS_H_
+
+#include "format.h"
+
+#ifndef FMT_MODULE
+#  include <cerrno>
+#  include <cstddef>
+#  include <cstdio>
+#  include <system_error>  // std::system_error
+
+#  if FMT_HAS_INCLUDE(<xlocale.h>)
+#    include <xlocale.h>  // LC_NUMERIC_MASK on macOS
+#  endif
+#endif  // FMT_MODULE
+
+#ifndef FMT_USE_FCNTL
+// UWP doesn't provide _pipe.
+#  if FMT_HAS_INCLUDE("winapifamily.h")
+#    include <winapifamily.h>
+#  endif
+#  if (FMT_HAS_INCLUDE(<fcntl.h>) || defined(__APPLE__) || \
+       defined(__linux__)) &&                              \
+      (!defined(WINAPI_FAMILY) ||                          \
+       (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP))
+#    include <fcntl.h>  // for O_RDONLY
+#    define FMT_USE_FCNTL 1
+#  else
+#    define FMT_USE_FCNTL 0
+#  endif
+#endif
+
+#ifndef FMT_POSIX
+#  if defined(_WIN32) && !defined(__MINGW32__)
+// Fix warnings about deprecated symbols.
+#    define FMT_POSIX(call) _##call
+#  else
+#    define FMT_POSIX(call) call
+#  endif
+#endif
+
+// Calls to system functions are wrapped in FMT_SYSTEM for testability.
+#ifdef FMT_SYSTEM
+#  define FMT_HAS_SYSTEM
+#  define FMT_POSIX_CALL(call) FMT_SYSTEM(call)
+#else
+#  define FMT_SYSTEM(call) ::call
+#  ifdef _WIN32
+// Fix warnings about deprecated symbols.
+#    define FMT_POSIX_CALL(call) ::_##call
+#  else
+#    define FMT_POSIX_CALL(call) ::call
+#  endif
+#endif
+
+// Retries the expression while it evaluates to error_result and errno
+// equals to EINTR.
+#ifndef _WIN32
+#  define FMT_RETRY_VAL(result, expression, error_result) \
+    do {                                                  \
+      (result) = (expression);                            \
+    } while ((result) == (error_result) && errno == EINTR)
+#else
+#  define FMT_RETRY_VAL(result, expression, error_result) result = (expression)
+#endif
+
+#define FMT_RETRY(result, expression) FMT_RETRY_VAL(result, expression, -1)
+
+FMT_BEGIN_NAMESPACE
+FMT_BEGIN_EXPORT
+
+/**
+ * A reference to a null-terminated string. It can be constructed from a C
+ * string or `std::string`.
+ *
+ * You can use one of the following type aliases for common character types:
+ *
+ * +---------------+-----------------------------+
+ * | Type          | Definition                  |
+ * +===============+=============================+
+ * | cstring_view  | basic_cstring_view<char>    |
+ * +---------------+-----------------------------+
+ * | wcstring_view | basic_cstring_view<wchar_t> |
+ * +---------------+-----------------------------+
+ *
+ * This class is most useful as a parameter type for functions that wrap C APIs.
+ */
+template <typename Char> class basic_cstring_view {
+ private:
+  const Char* data_;
+
+ public:
+  /// Constructs a string reference object from a C string.
+  basic_cstring_view(const Char* s) : data_(s) {}
+
+  /// Constructs a string reference from an `std::string` object.
+  basic_cstring_view(const std::basic_string<Char>& s) : data_(s.c_str()) {}
+
+  /// Returns the pointer to a C string.
+  auto c_str() const -> const Char* { return data_; }
+};
+
+using cstring_view = basic_cstring_view<char>;
+using wcstring_view = basic_cstring_view<wchar_t>;
+
+#ifdef _WIN32
+FMT_API const std::error_category& system_category() noexcept;
+
+namespace detail {
+FMT_API void format_windows_error(buffer<char>& out, int error_code,
+                                  const char* message) noexcept;
+}
+
+FMT_API std::system_error vwindows_error(int error_code, string_view fmt,
+                                         format_args args);
+
+/**
+ * Constructs a `std::system_error` object with the description of the form
+ *
+ *     <message>: <system-message>
+ *
+ * where `<message>` is the formatted message and `<system-message>` is the
+ * system message corresponding to the error code.
+ * `error_code` is a Windows error code as given by `GetLastError`.
+ * If `error_code` is not a valid error code such as -1, the system message
+ * will look like "error -1".
+ *
+ * **Example**:
+ *
+ *     // This throws a system_error with the description
+ *     //   cannot open file 'madeup': The system cannot find the file
+ * specified.
+ *     // or similar (system message may vary).
+ *     const char *filename = "madeup";
+ *     LPOFSTRUCT of = LPOFSTRUCT();
+ *     HFILE file = OpenFile(filename, &of, OF_READ);
+ *     if (file == HFILE_ERROR) {
+ *       throw fmt::windows_error(GetLastError(),
+ *                                "cannot open file '{}'", filename);
+ *     }
+ */
+template <typename... T>
+auto windows_error(int error_code, string_view message, const T&... args)
+    -> std::system_error {
+  return vwindows_error(error_code, message, vargs<T...>{{args...}});
+}
+
+// Reports a Windows error without throwing an exception.
+// Can be used to report errors from destructors.
+FMT_API void report_windows_error(int error_code, const char* message) noexcept;
+#else
+inline auto system_category() noexcept -> const std::error_category& {
+  return std::system_category();
+}
+#endif  // _WIN32
+
+// std::system is not available on some platforms such as iOS (#2248).
+#ifdef __OSX__
+template <typename S, typename... Args, typename Char = char_t<S>>
+void say(const S& fmt, Args&&... args) {
+  std::system(format("say \"{}\"", format(fmt, args...)).c_str());
+}
+#endif
+
+// A buffered file.
+class buffered_file {
+ private:
+  FILE* file_;
+
+  friend class file;
+
+  inline explicit buffered_file(FILE* f) : file_(f) {}
+
+ public:
+  buffered_file(const buffered_file&) = delete;
+  void operator=(const buffered_file&) = delete;
+
+  // Constructs a buffered_file object which doesn't represent any file.
+  inline buffered_file() noexcept : file_(nullptr) {}
+
+  // Destroys the object closing the file it represents if any.
+  FMT_API ~buffered_file() noexcept;
+
+ public:
+  inline buffered_file(buffered_file&& other) noexcept : file_(other.file_) {
+    other.file_ = nullptr;
+  }
+
+  inline auto operator=(buffered_file&& other) -> buffered_file& {
+    close();
+    file_ = other.file_;
+    other.file_ = nullptr;
+    return *this;
+  }
+
+  // Opens a file.
+  FMT_API buffered_file(cstring_view filename, cstring_view mode);
+
+  // Closes the file.
+  FMT_API void close();
+
+  // Returns the pointer to a FILE object representing this file.
+  inline auto get() const noexcept -> FILE* { return file_; }
+
+  FMT_API auto descriptor() const -> int;
+
+  template <typename... T>
+  inline void print(string_view fmt, const T&... args) {
+    fmt::vargs<T...> vargs = {{args...}};
+    detail::is_locking<T...>() ? fmt::vprint_buffered(file_, fmt, vargs)
+                               : fmt::vprint(file_, fmt, vargs);
+  }
+};
+
+#if FMT_USE_FCNTL
+
+// A file. Closed file is represented by a file object with descriptor -1.
+// Methods that are not declared with noexcept may throw
+// fmt::system_error in case of failure. Note that some errors such as
+// closing the file multiple times will cause a crash on Windows rather
+// than an exception. You can get standard behavior by overriding the
+// invalid parameter handler with _set_invalid_parameter_handler.
+class FMT_API file {
+ private:
+  int fd_;  // File descriptor.
+
+  // Constructs a file object with a given descriptor.
+  explicit file(int fd) : fd_(fd) {}
+
+  friend struct pipe;
+
+ public:
+  // Possible values for the oflag argument to the constructor.
+  enum {
+    RDONLY = FMT_POSIX(O_RDONLY),  // Open for reading only.
+    WRONLY = FMT_POSIX(O_WRONLY),  // Open for writing only.
+    RDWR = FMT_POSIX(O_RDWR),      // Open for reading and writing.
+    CREATE = FMT_POSIX(O_CREAT),   // Create if the file doesn't exist.
+    APPEND = FMT_POSIX(O_APPEND),  // Open in append mode.
+    TRUNC = FMT_POSIX(O_TRUNC)     // Truncate the content of the file.
+  };
+
+  // Constructs a file object which doesn't represent any file.
+  inline file() noexcept : fd_(-1) {}
+
+  // Opens a file and constructs a file object representing this file.
+  file(cstring_view path, int oflag);
+
+ public:
+  file(const file&) = delete;
+  void operator=(const file&) = delete;
+
+  inline file(file&& other) noexcept : fd_(other.fd_) { other.fd_ = -1; }
+
+  // Move assignment is not noexcept because close may throw.
+  inline auto operator=(file&& other) -> file& {
+    close();
+    fd_ = other.fd_;
+    other.fd_ = -1;
+    return *this;
+  }
+
+  // Destroys the object closing the file it represents if any.
+  ~file() noexcept;
+
+  // Returns the file descriptor.
+  inline auto descriptor() const noexcept -> int { return fd_; }
+
+  // Closes the file.
+  void close();
+
+  // Returns the file size. The size has signed type for consistency with
+  // stat::st_size.
+  auto size() const -> long long;
+
+  // Attempts to read count bytes from the file into the specified buffer.
+  auto read(void* buffer, size_t count) -> size_t;
+
+  // Attempts to write count bytes from the specified buffer to the file.
+  auto write(const void* buffer, size_t count) -> size_t;
+
+  // Duplicates a file descriptor with the dup function and returns
+  // the duplicate as a file object.
+  static auto dup(int fd) -> file;
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  void dup2(int fd);
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  void dup2(int fd, std::error_code& ec) noexcept;
+
+  // Creates a buffered_file object associated with this file and detaches
+  // this file object from the file.
+  auto fdopen(const char* mode) -> buffered_file;
+
+#  if defined(_WIN32) && !defined(__MINGW32__)
+  // Opens a file and constructs a file object representing this file by
+  // wcstring_view filename. Windows only.
+  static file open_windows_file(wcstring_view path, int oflag);
+#  endif
+};
+
+struct FMT_API pipe {
+  file read_end;
+  file write_end;
+
+  // Creates a pipe setting up read_end and write_end file objects for reading
+  // and writing respectively.
+  pipe();
+};
+
+// Returns the memory page size.
+auto getpagesize() -> long;
+
+namespace detail {
+
+struct buffer_size {
+  constexpr buffer_size() = default;
+  size_t value = 0;
+  FMT_CONSTEXPR auto operator=(size_t val) const -> buffer_size {
+    auto bs = buffer_size();
+    bs.value = val;
+    return bs;
+  }
+};
+
+struct ostream_params {
+  int oflag = file::WRONLY | file::CREATE | file::TRUNC;
+  size_t buffer_size = BUFSIZ > 32768 ? BUFSIZ : 32768;
+
+  constexpr ostream_params() {}
+
+  template <typename... T>
+  ostream_params(T... params, int new_oflag) : ostream_params(params...) {
+    oflag = new_oflag;
+  }
+
+  template <typename... T>
+  ostream_params(T... params, detail::buffer_size bs)
+      : ostream_params(params...) {
+    this->buffer_size = bs.value;
+  }
+
+// Intel has a bug that results in failure to deduce a constructor
+// for empty parameter packs.
+#  if defined(__INTEL_COMPILER) && __INTEL_COMPILER < 2000
+  ostream_params(int new_oflag) : oflag(new_oflag) {}
+  ostream_params(detail::buffer_size bs) : buffer_size(bs.value) {}
+#  endif
+};
+
+}  // namespace detail
+
+FMT_INLINE_VARIABLE constexpr auto buffer_size = detail::buffer_size();
+
+/// A fast buffered output stream for writing from a single thread. Writing from
+/// multiple threads without external synchronization may result in a data race.
+class FMT_API ostream : private detail::buffer<char> {
+ private:
+  file file_;
+
+  ostream(cstring_view path, const detail::ostream_params& params);
+
+  static void grow(buffer<char>& buf, size_t);
+
+ public:
+  ostream(ostream&& other) noexcept;
+  ~ostream();
+
+  operator writer() {
+    detail::buffer<char>& buf = *this;
+    return buf;
+  }
+
+  inline void flush() {
+    if (size() == 0) return;
+    file_.write(data(), size() * sizeof(data()[0]));
+    clear();
+  }
+
+  template <typename... T>
+  friend auto output_file(cstring_view path, T... params) -> ostream;
+
+  inline void close() {
+    flush();
+    file_.close();
+  }
+
+  /// Formats `args` according to specifications in `fmt` and writes the
+  /// output to the file.
+  template <typename... T> void print(format_string<T...> fmt, T&&... args) {
+    vformat_to(appender(*this), fmt.str, vargs<T...>{{args...}});
+  }
+};
+
+/**
+ * Opens a file for writing. Supported parameters passed in `params`:
+ *
+ * - `<integer>`: Flags passed to [open](
+ *   https://pubs.opengroup.org/onlinepubs/007904875/functions/open.html)
+ *   (`file::WRONLY | file::CREATE | file::TRUNC` by default)
+ * - `buffer_size=<integer>`: Output buffer size
+ *
+ * **Example**:
+ *
+ *     auto out = fmt::output_file("guide.txt");
+ *     out.print("Don't {}", "Panic");
+ */
+template <typename... T>
+inline auto output_file(cstring_view path, T... params) -> ostream {
+  return {path, detail::ostream_params(params...)};
+}
+#endif  // FMT_USE_FCNTL
+
+FMT_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_OS_H_

extlib/libfmt/include/fmt/ostream.h

@@ -0,0 +1,166 @@
+// Formatting library for C++ - std::ostream support
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_OSTREAM_H_
+#define FMT_OSTREAM_H_
+
+#ifndef FMT_MODULE
+#  include <fstream>  // std::filebuf
+#endif
+
+#ifdef _WIN32
+#  ifdef __GLIBCXX__
+#    include <ext/stdio_filebuf.h>
+#    include <ext/stdio_sync_filebuf.h>
+#  endif
+#  include <io.h>
+#endif
+
+#include "chrono.h"  // formatbuf
+
+#ifdef _MSVC_STL_UPDATE
+#  define FMT_MSVC_STL_UPDATE _MSVC_STL_UPDATE
+#elif defined(_MSC_VER) && _MSC_VER < 1912  // VS 15.5
+#  define FMT_MSVC_STL_UPDATE _MSVC_LANG
+#else
+#  define FMT_MSVC_STL_UPDATE 0
+#endif
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+// Generate a unique explicit instantion in every translation unit using a tag
+// type in an anonymous namespace.
+namespace {
+struct file_access_tag {};
+}  // namespace
+template <typename Tag, typename BufType, FILE* BufType::*FileMemberPtr>
+class file_access {
+  friend auto get_file(BufType& obj) -> FILE* { return obj.*FileMemberPtr; }
+};
+
+#if FMT_MSVC_STL_UPDATE
+template class file_access<file_access_tag, std::filebuf,
+                           &std::filebuf::_Myfile>;
+auto get_file(std::filebuf&) -> FILE*;
+#endif
+
+// Write the content of buf to os.
+// It is a separate function rather than a part of vprint to simplify testing.
+template <typename Char>
+void write_buffer(std::basic_ostream<Char>& os, buffer<Char>& buf) {
+  const Char* buf_data = buf.data();
+  using unsigned_streamsize = make_unsigned_t<std::streamsize>;
+  unsigned_streamsize size = buf.size();
+  unsigned_streamsize max_size = to_unsigned(max_value<std::streamsize>());
+  do {
+    unsigned_streamsize n = size <= max_size ? size : max_size;
+    os.write(buf_data, static_cast<std::streamsize>(n));
+    buf_data += n;
+    size -= n;
+  } while (size != 0);
+}
+
+template <typename T> struct streamed_view {
+  const T& value;
+};
+}  // namespace detail
+
+// Formats an object of type T that has an overloaded ostream operator<<.
+template <typename Char>
+struct basic_ostream_formatter : formatter<basic_string_view<Char>, Char> {
+  void set_debug_format() = delete;
+
+  template <typename T, typename Context>
+  auto format(const T& value, Context& ctx) const -> decltype(ctx.out()) {
+    auto buffer = basic_memory_buffer<Char>();
+    auto&& formatbuf = detail::formatbuf<std::basic_streambuf<Char>>(buffer);
+    auto&& output = std::basic_ostream<Char>(&formatbuf);
+    output.imbue(std::locale::classic());  // The default is always unlocalized.
+    output << value;
+    output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
+    return formatter<basic_string_view<Char>, Char>::format(
+        {buffer.data(), buffer.size()}, ctx);
+  }
+};
+
+using ostream_formatter = basic_ostream_formatter<char>;
+
+template <typename T, typename Char>
+struct formatter<detail::streamed_view<T>, Char>
+    : basic_ostream_formatter<Char> {
+  template <typename Context>
+  auto format(detail::streamed_view<T> view, Context& ctx) const
+      -> decltype(ctx.out()) {
+    return basic_ostream_formatter<Char>::format(view.value, ctx);
+  }
+};
+
+/**
+ * Returns a view that formats `value` via an ostream `operator<<`.
+ *
+ * **Example**:
+ *
+ *     fmt::print("Current thread id: {}\n",
+ *                fmt::streamed(std::this_thread::get_id()));
+ */
+template <typename T>
+constexpr auto streamed(const T& value) -> detail::streamed_view<T> {
+  return {value};
+}
+
+inline void vprint(std::ostream& os, string_view fmt, format_args args) {
+  auto buffer = memory_buffer();
+  detail::vformat_to(buffer, fmt, args);
+  FILE* f = nullptr;
+#if FMT_MSVC_STL_UPDATE && FMT_USE_RTTI
+  if (auto* buf = dynamic_cast<std::filebuf*>(os.rdbuf()))
+    f = detail::get_file(*buf);
+#elif defined(_WIN32) && defined(__GLIBCXX__) && FMT_USE_RTTI
+  auto* rdbuf = os.rdbuf();
+  if (auto* sfbuf = dynamic_cast<__gnu_cxx::stdio_sync_filebuf<char>*>(rdbuf))
+    f = sfbuf->file();
+  else if (auto* fbuf = dynamic_cast<__gnu_cxx::stdio_filebuf<char>*>(rdbuf))
+    f = fbuf->file();
+#endif
+#ifdef _WIN32
+  if (f) {
+    int fd = _fileno(f);
+    if (_isatty(fd)) {
+      os.flush();
+      if (detail::write_console(fd, {buffer.data(), buffer.size()})) return;
+    }
+  }
+#endif
+  detail::ignore_unused(f);
+  detail::write_buffer(os, buffer);
+}
+
+/**
+ * Prints formatted data to the stream `os`.
+ *
+ * **Example**:
+ *
+ *     fmt::print(cerr, "Don't {}!", "panic");
+ */
+FMT_EXPORT template <typename... T>
+void print(std::ostream& os, format_string<T...> fmt, T&&... args) {
+  fmt::vargs<T...> vargs = {{args...}};
+  if (detail::use_utf8) return vprint(os, fmt.str, vargs);
+  auto buffer = memory_buffer();
+  detail::vformat_to(buffer, fmt.str, vargs);
+  detail::write_buffer(os, buffer);
+}
+
+FMT_EXPORT template <typename... T>
+void println(std::ostream& os, format_string<T...> fmt, T&&... args) {
+  fmt::print(os, "{}\n", fmt::format(fmt, std::forward<T>(args)...));
+}
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_OSTREAM_H_

extlib/libfmt/include/fmt/printf.h

@@ -0,0 +1,633 @@
+// Formatting library for C++ - legacy printf implementation
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_PRINTF_H_
+#define FMT_PRINTF_H_
+
+#ifndef FMT_MODULE
+#  include <algorithm>  // std::max
+#  include <limits>     // std::numeric_limits
+#endif
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+FMT_BEGIN_EXPORT
+
+template <typename T> struct printf_formatter {
+  printf_formatter() = delete;
+};
+
+template <typename Char> class basic_printf_context {
+ private:
+  basic_appender<Char> out_;
+  basic_format_args<basic_printf_context> args_;
+
+  static_assert(std::is_same<Char, char>::value ||
+                    std::is_same<Char, wchar_t>::value,
+                "Unsupported code unit type.");
+
+ public:
+  using char_type = Char;
+  using parse_context_type = parse_context<Char>;
+  template <typename T> using formatter_type = printf_formatter<T>;
+  enum { builtin_types = 1 };
+
+  /// Constructs a `printf_context` object. References to the arguments are
+  /// stored in the context object so make sure they have appropriate lifetimes.
+  basic_printf_context(basic_appender<Char> out,
+                       basic_format_args<basic_printf_context> args)
+      : out_(out), args_(args) {}
+
+  auto out() -> basic_appender<Char> { return out_; }
+  void advance_to(basic_appender<Char>) {}
+
+  auto locale() -> detail::locale_ref { return {}; }
+
+  auto arg(int id) const -> basic_format_arg<basic_printf_context> {
+    return args_.get(id);
+  }
+};
+
+namespace detail {
+
+// Return the result via the out param to workaround gcc bug 77539.
+template <bool IS_CONSTEXPR, typename T, typename Ptr = const T*>
+FMT_CONSTEXPR auto find(Ptr first, Ptr last, T value, Ptr& out) -> bool {
+  for (out = first; out != last; ++out) {
+    if (*out == value) return true;
+  }
+  return false;
+}
+
+template <>
+inline auto find<false, char>(const char* first, const char* last, char value,
+                              const char*& out) -> bool {
+  out =
+      static_cast<const char*>(memchr(first, value, to_unsigned(last - first)));
+  return out != nullptr;
+}
+
+// Checks if a value fits in int - used to avoid warnings about comparing
+// signed and unsigned integers.
+template <bool IsSigned> struct int_checker {
+  template <typename T> static auto fits_in_int(T value) -> bool {
+    unsigned max = to_unsigned(max_value<int>());
+    return value <= max;
+  }
+  inline static auto fits_in_int(bool) -> bool { return true; }
+};
+
+template <> struct int_checker<true> {
+  template <typename T> static auto fits_in_int(T value) -> bool {
+    return value >= (std::numeric_limits<int>::min)() &&
+           value <= max_value<int>();
+  }
+  inline static auto fits_in_int(int) -> bool { return true; }
+};
+
+struct printf_precision_handler {
+  template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+  auto operator()(T value) -> int {
+    if (!int_checker<std::numeric_limits<T>::is_signed>::fits_in_int(value))
+      report_error("number is too big");
+    return (std::max)(static_cast<int>(value), 0);
+  }
+
+  template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
+  auto operator()(T) -> int {
+    report_error("precision is not integer");
+    return 0;
+  }
+};
+
+// An argument visitor that returns true iff arg is a zero integer.
+struct is_zero_int {
+  template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+  auto operator()(T value) -> bool {
+    return value == 0;
+  }
+
+  template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
+  auto operator()(T) -> bool {
+    return false;
+  }
+};
+
+template <typename T> struct make_unsigned_or_bool : std::make_unsigned<T> {};
+
+template <> struct make_unsigned_or_bool<bool> {
+  using type = bool;
+};
+
+template <typename T, typename Context> class arg_converter {
+ private:
+  using char_type = typename Context::char_type;
+
+  basic_format_arg<Context>& arg_;
+  char_type type_;
+
+ public:
+  arg_converter(basic_format_arg<Context>& arg, char_type type)
+      : arg_(arg), type_(type) {}
+
+  void operator()(bool value) {
+    if (type_ != 's') operator()<bool>(value);
+  }
+
+  template <typename U, FMT_ENABLE_IF(std::is_integral<U>::value)>
+  void operator()(U value) {
+    bool is_signed = type_ == 'd' || type_ == 'i';
+    using target_type = conditional_t<std::is_same<T, void>::value, U, T>;
+    if (const_check(sizeof(target_type) <= sizeof(int))) {
+      // Extra casts are used to silence warnings.
+      using unsigned_type = typename make_unsigned_or_bool<target_type>::type;
+      if (is_signed)
+        arg_ = static_cast<int>(static_cast<target_type>(value));
+      else
+        arg_ = static_cast<unsigned>(static_cast<unsigned_type>(value));
+    } else {
+      // glibc's printf doesn't sign extend arguments of smaller types:
+      //   std::printf("%lld", -42);  // prints "4294967254"
+      // but we don't have to do the same because it's a UB.
+      if (is_signed)
+        arg_ = static_cast<long long>(value);
+      else
+        arg_ = static_cast<typename make_unsigned_or_bool<U>::type>(value);
+    }
+  }
+
+  template <typename U, FMT_ENABLE_IF(!std::is_integral<U>::value)>
+  void operator()(U) {}  // No conversion needed for non-integral types.
+};
+
+// Converts an integer argument to T for printf, if T is an integral type.
+// If T is void, the argument is converted to corresponding signed or unsigned
+// type depending on the type specifier: 'd' and 'i' - signed, other -
+// unsigned).
+template <typename T, typename Context, typename Char>
+void convert_arg(basic_format_arg<Context>& arg, Char type) {
+  arg.visit(arg_converter<T, Context>(arg, type));
+}
+
+// Converts an integer argument to char for printf.
+template <typename Context> class char_converter {
+ private:
+  basic_format_arg<Context>& arg_;
+
+ public:
+  explicit char_converter(basic_format_arg<Context>& arg) : arg_(arg) {}
+
+  template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+  void operator()(T value) {
+    arg_ = static_cast<typename Context::char_type>(value);
+  }
+
+  template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
+  void operator()(T) {}  // No conversion needed for non-integral types.
+};
+
+// An argument visitor that return a pointer to a C string if argument is a
+// string or null otherwise.
+template <typename Char> struct get_cstring {
+  template <typename T> auto operator()(T) -> const Char* { return nullptr; }
+  auto operator()(const Char* s) -> const Char* { return s; }
+};
+
+// Checks if an argument is a valid printf width specifier and sets
+// left alignment if it is negative.
+class printf_width_handler {
+ private:
+  format_specs& specs_;
+
+ public:
+  inline explicit printf_width_handler(format_specs& specs) : specs_(specs) {}
+
+  template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+  auto operator()(T value) -> unsigned {
+    auto width = static_cast<uint32_or_64_or_128_t<T>>(value);
+    if (detail::is_negative(value)) {
+      specs_.set_align(align::left);
+      width = 0 - width;
+    }
+    unsigned int_max = to_unsigned(max_value<int>());
+    if (width > int_max) report_error("number is too big");
+    return static_cast<unsigned>(width);
+  }
+
+  template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
+  auto operator()(T) -> unsigned {
+    report_error("width is not integer");
+    return 0;
+  }
+};
+
+// Workaround for a bug with the XL compiler when initializing
+// printf_arg_formatter's base class.
+template <typename Char>
+auto make_arg_formatter(basic_appender<Char> iter, format_specs& s)
+    -> arg_formatter<Char> {
+  return {iter, s, locale_ref()};
+}
+
+// The `printf` argument formatter.
+template <typename Char>
+class printf_arg_formatter : public arg_formatter<Char> {
+ private:
+  using base = arg_formatter<Char>;
+  using context_type = basic_printf_context<Char>;
+
+  context_type& context_;
+
+  void write_null_pointer(bool is_string = false) {
+    auto s = this->specs;
+    s.set_type(presentation_type::none);
+    write_bytes<Char>(this->out, is_string ? "(null)" : "(nil)", s);
+  }
+
+  template <typename T> void write(T value) {
+    detail::write<Char>(this->out, value, this->specs, this->locale);
+  }
+
+ public:
+  printf_arg_formatter(basic_appender<Char> iter, format_specs& s,
+                       context_type& ctx)
+      : base(make_arg_formatter(iter, s)), context_(ctx) {}
+
+  void operator()(monostate value) { write(value); }
+
+  template <typename T, FMT_ENABLE_IF(detail::is_integral<T>::value)>
+  void operator()(T value) {
+    // MSVC2013 fails to compile separate overloads for bool and Char so use
+    // std::is_same instead.
+    if (!std::is_same<T, Char>::value) {
+      write(value);
+      return;
+    }
+    format_specs s = this->specs;
+    if (s.type() != presentation_type::none &&
+        s.type() != presentation_type::chr) {
+      return (*this)(static_cast<int>(value));
+    }
+    s.set_sign(sign::none);
+    s.clear_alt();
+    s.set_fill(' ');  // Ignore '0' flag for char types.
+    // align::numeric needs to be overwritten here since the '0' flag is
+    // ignored for non-numeric types
+    if (s.align() == align::none || s.align() == align::numeric)
+      s.set_align(align::right);
+    detail::write<Char>(this->out, static_cast<Char>(value), s);
+  }
+
+  template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
+  void operator()(T value) {
+    write(value);
+  }
+
+  void operator()(const char* value) {
+    if (value)
+      write(value);
+    else
+      write_null_pointer(this->specs.type() != presentation_type::pointer);
+  }
+
+  void operator()(const wchar_t* value) {
+    if (value)
+      write(value);
+    else
+      write_null_pointer(this->specs.type() != presentation_type::pointer);
+  }
+
+  void operator()(basic_string_view<Char> value) { write(value); }
+
+  void operator()(const void* value) {
+    if (value)
+      write(value);
+    else
+      write_null_pointer();
+  }
+
+  void operator()(typename basic_format_arg<context_type>::handle handle) {
+    auto parse_ctx = parse_context<Char>({});
+    handle.format(parse_ctx, context_);
+  }
+};
+
+template <typename Char>
+void parse_flags(format_specs& specs, const Char*& it, const Char* end) {
+  for (; it != end; ++it) {
+    switch (*it) {
+    case '-': specs.set_align(align::left); break;
+    case '+': specs.set_sign(sign::plus); break;
+    case '0': specs.set_fill('0'); break;
+    case ' ':
+      if (specs.sign() != sign::plus) specs.set_sign(sign::space);
+      break;
+    case '#': specs.set_alt(); break;
+    default:  return;
+    }
+  }
+}
+
+template <typename Char, typename GetArg>
+auto parse_header(const Char*& it, const Char* end, format_specs& specs,
+                  GetArg get_arg) -> int {
+  int arg_index = -1;
+  Char c = *it;
+  if (c >= '0' && c <= '9') {
+    // Parse an argument index (if followed by '$') or a width possibly
+    // preceded with '0' flag(s).
+    int value = parse_nonnegative_int(it, end, -1);
+    if (it != end && *it == '$') {  // value is an argument index
+      ++it;
+      arg_index = value != -1 ? value : max_value<int>();
+    } else {
+      if (c == '0') specs.set_fill('0');
+      if (value != 0) {
+        // Nonzero value means that we parsed width and don't need to
+        // parse it or flags again, so return now.
+        if (value == -1) report_error("number is too big");
+        specs.width = value;
+        return arg_index;
+      }
+    }
+  }
+  parse_flags(specs, it, end);
+  // Parse width.
+  if (it != end) {
+    if (*it >= '0' && *it <= '9') {
+      specs.width = parse_nonnegative_int(it, end, -1);
+      if (specs.width == -1) report_error("number is too big");
+    } else if (*it == '*') {
+      ++it;
+      specs.width = static_cast<int>(
+          get_arg(-1).visit(detail::printf_width_handler(specs)));
+    }
+  }
+  return arg_index;
+}
+
+inline auto parse_printf_presentation_type(char c, type t, bool& upper)
+    -> presentation_type {
+  using pt = presentation_type;
+  constexpr auto integral_set = sint_set | uint_set | bool_set | char_set;
+  switch (c) {
+  case 'd': return in(t, integral_set) ? pt::dec : pt::none;
+  case 'o': return in(t, integral_set) ? pt::oct : pt::none;
+  case 'X': upper = true; FMT_FALLTHROUGH;
+  case 'x': return in(t, integral_set) ? pt::hex : pt::none;
+  case 'E': upper = true; FMT_FALLTHROUGH;
+  case 'e': return in(t, float_set) ? pt::exp : pt::none;
+  case 'F': upper = true; FMT_FALLTHROUGH;
+  case 'f': return in(t, float_set) ? pt::fixed : pt::none;
+  case 'G': upper = true; FMT_FALLTHROUGH;
+  case 'g': return in(t, float_set) ? pt::general : pt::none;
+  case 'A': upper = true; FMT_FALLTHROUGH;
+  case 'a': return in(t, float_set) ? pt::hexfloat : pt::none;
+  case 'c': return in(t, integral_set) ? pt::chr : pt::none;
+  case 's': return in(t, string_set | cstring_set) ? pt::string : pt::none;
+  case 'p': return in(t, pointer_set | cstring_set) ? pt::pointer : pt::none;
+  default:  return pt::none;
+  }
+}
+
+template <typename Char, typename Context>
+void vprintf(buffer<Char>& buf, basic_string_view<Char> format,
+             basic_format_args<Context> args) {
+  using iterator = basic_appender<Char>;
+  auto out = iterator(buf);
+  auto context = basic_printf_context<Char>(out, args);
+  auto parse_ctx = parse_context<Char>(format);
+
+  // Returns the argument with specified index or, if arg_index is -1, the next
+  // argument.
+  auto get_arg = [&](int arg_index) {
+    if (arg_index < 0)
+      arg_index = parse_ctx.next_arg_id();
+    else
+      parse_ctx.check_arg_id(--arg_index);
+    return detail::get_arg(context, arg_index);
+  };
+
+  const Char* start = parse_ctx.begin();
+  const Char* end = parse_ctx.end();
+  auto it = start;
+  while (it != end) {
+    if (!find<false, Char>(it, end, '%', it)) {
+      it = end;  // find leaves it == nullptr if it doesn't find '%'.
+      break;
+    }
+    Char c = *it++;
+    if (it != end && *it == c) {
+      write(out, basic_string_view<Char>(start, to_unsigned(it - start)));
+      start = ++it;
+      continue;
+    }
+    write(out, basic_string_view<Char>(start, to_unsigned(it - 1 - start)));
+
+    auto specs = format_specs();
+    specs.set_align(align::right);
+
+    // Parse argument index, flags and width.
+    int arg_index = parse_header(it, end, specs, get_arg);
+    if (arg_index == 0) report_error("argument not found");
+
+    // Parse precision.
+    if (it != end && *it == '.') {
+      ++it;
+      c = it != end ? *it : 0;
+      if ('0' <= c && c <= '9') {
+        specs.precision = parse_nonnegative_int(it, end, 0);
+      } else if (c == '*') {
+        ++it;
+        specs.precision =
+            static_cast<int>(get_arg(-1).visit(printf_precision_handler()));
+      } else {
+        specs.precision = 0;
+      }
+    }
+
+    auto arg = get_arg(arg_index);
+    // For d, i, o, u, x, and X conversion specifiers, if a precision is
+    // specified, the '0' flag is ignored
+    if (specs.precision >= 0 && is_integral_type(arg.type())) {
+      // Ignore '0' for non-numeric types or if '-' present.
+      specs.set_fill(' ');
+    }
+    if (specs.precision >= 0 && arg.type() == type::cstring_type) {
+      auto str = arg.visit(get_cstring<Char>());
+      auto str_end = str + specs.precision;
+      auto nul = std::find(str, str_end, Char());
+      auto sv = basic_string_view<Char>(
+          str, to_unsigned(nul != str_end ? nul - str : specs.precision));
+      arg = sv;
+    }
+    if (specs.alt() && arg.visit(is_zero_int())) specs.clear_alt();
+    if (specs.fill_unit<Char>() == '0') {
+      if (is_arithmetic_type(arg.type()) && specs.align() != align::left) {
+        specs.set_align(align::numeric);
+      } else {
+        // Ignore '0' flag for non-numeric types or if '-' flag is also present.
+        specs.set_fill(' ');
+      }
+    }
+
+    // Parse length and convert the argument to the required type.
+    c = it != end ? *it++ : 0;
+    Char t = it != end ? *it : 0;
+    switch (c) {
+    case 'h':
+      if (t == 'h') {
+        ++it;
+        t = it != end ? *it : 0;
+        convert_arg<signed char>(arg, t);
+      } else {
+        convert_arg<short>(arg, t);
+      }
+      break;
+    case 'l':
+      if (t == 'l') {
+        ++it;
+        t = it != end ? *it : 0;
+        convert_arg<long long>(arg, t);
+      } else {
+        convert_arg<long>(arg, t);
+      }
+      break;
+    case 'j': convert_arg<intmax_t>(arg, t); break;
+    case 'z': convert_arg<size_t>(arg, t); break;
+    case 't': convert_arg<std::ptrdiff_t>(arg, t); break;
+    case 'L':
+      // printf produces garbage when 'L' is omitted for long double, no
+      // need to do the same.
+      break;
+    default: --it; convert_arg<void>(arg, c);
+    }
+
+    // Parse type.
+    if (it == end) report_error("invalid format string");
+    char type = static_cast<char>(*it++);
+    if (is_integral_type(arg.type())) {
+      // Normalize type.
+      switch (type) {
+      case 'i':
+      case 'u': type = 'd'; break;
+      case 'c':
+        arg.visit(char_converter<basic_printf_context<Char>>(arg));
+        break;
+      }
+    }
+    bool upper = false;
+    specs.set_type(parse_printf_presentation_type(type, arg.type(), upper));
+    if (specs.type() == presentation_type::none)
+      report_error("invalid format specifier");
+    if (upper) specs.set_upper();
+
+    start = it;
+
+    // Format argument.
+    arg.visit(printf_arg_formatter<Char>(out, specs, context));
+  }
+  write(out, basic_string_view<Char>(start, to_unsigned(it - start)));
+}
+}  // namespace detail
+
+using printf_context = basic_printf_context<char>;
+using wprintf_context = basic_printf_context<wchar_t>;
+
+using printf_args = basic_format_args<printf_context>;
+using wprintf_args = basic_format_args<wprintf_context>;
+
+/// Constructs an `format_arg_store` object that contains references to
+/// arguments and can be implicitly converted to `printf_args`.
+template <typename Char = char, typename... T>
+inline auto make_printf_args(T&... args)
+    -> decltype(fmt::make_format_args<basic_printf_context<Char>>(args...)) {
+  return fmt::make_format_args<basic_printf_context<Char>>(args...);
+}
+
+template <typename Char> struct vprintf_args {
+  using type = basic_format_args<basic_printf_context<Char>>;
+};
+
+template <typename Char>
+inline auto vsprintf(basic_string_view<Char> fmt,
+                     typename vprintf_args<Char>::type args)
+    -> std::basic_string<Char> {
+  auto buf = basic_memory_buffer<Char>();
+  detail::vprintf(buf, fmt, args);
+  return {buf.data(), buf.size()};
+}
+
+/**
+ * Formats `args` according to specifications in `fmt` and returns the result
+ * as as string.
+ *
+ * **Example**:
+ *
+ *     std::string message = fmt::sprintf("The answer is %d", 42);
+ */
+template <typename S, typename... T, typename Char = detail::char_t<S>>
+inline auto sprintf(const S& fmt, const T&... args) -> std::basic_string<Char> {
+  return vsprintf(detail::to_string_view(fmt),
+                  fmt::make_format_args<basic_printf_context<Char>>(args...));
+}
+
+template <typename Char>
+inline auto vfprintf(std::FILE* f, basic_string_view<Char> fmt,
+                     typename vprintf_args<Char>::type args) -> int {
+  auto buf = basic_memory_buffer<Char>();
+  detail::vprintf(buf, fmt, args);
+  size_t size = buf.size();
+  return std::fwrite(buf.data(), sizeof(Char), size, f) < size
+             ? -1
+             : static_cast<int>(size);
+}
+
+/**
+ * Formats `args` according to specifications in `fmt` and writes the output
+ * to `f`.
+ *
+ * **Example**:
+ *
+ *     fmt::fprintf(stderr, "Don't %s!", "panic");
+ */
+template <typename S, typename... T, typename Char = detail::char_t<S>>
+inline auto fprintf(std::FILE* f, const S& fmt, const T&... args) -> int {
+  return vfprintf(f, detail::to_string_view(fmt),
+                  make_printf_args<Char>(args...));
+}
+
+template <typename Char>
+FMT_DEPRECATED inline auto vprintf(basic_string_view<Char> fmt,
+                                   typename vprintf_args<Char>::type args)
+    -> int {
+  return vfprintf(stdout, fmt, args);
+}
+
+/**
+ * Formats `args` according to specifications in `fmt` and writes the output
+ * to `stdout`.
+ *
+ * **Example**:
+ *
+ *   fmt::printf("Elapsed time: %.2f seconds", 1.23);
+ */
+template <typename... T>
+inline auto printf(string_view fmt, const T&... args) -> int {
+  return vfprintf(stdout, fmt, make_printf_args(args...));
+}
+template <typename... T>
+FMT_DEPRECATED inline auto printf(basic_string_view<wchar_t> fmt,
+                                  const T&... args) -> int {
+  return vfprintf(stdout, fmt, make_printf_args<wchar_t>(args...));
+}
+
+FMT_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_PRINTF_H_

extlib/libfmt/include/fmt/ranges.h

@@ -0,0 +1,848 @@
+// Formatting library for C++ - range and tuple support
+//
+// Copyright (c) 2012 - present, Victor Zverovich and {fmt} contributors
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_RANGES_H_
+#define FMT_RANGES_H_
+
+#ifndef FMT_MODULE
+#  include <initializer_list>
+#  include <iterator>
+#  include <string>
+#  include <tuple>
+#  include <type_traits>
+#  include <utility>
+#endif
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+
+FMT_EXPORT
+enum class range_format { disabled, map, set, sequence, string, debug_string };
+
+namespace detail {
+
+template <typename T> class is_map {
+  template <typename U> static auto check(U*) -> typename U::mapped_type;
+  template <typename> static void check(...);
+
+ public:
+  static constexpr const bool value =
+      !std::is_void<decltype(check<T>(nullptr))>::value;
+};
+
+template <typename T> class is_set {
+  template <typename U> static auto check(U*) -> typename U::key_type;
+  template <typename> static void check(...);
+
+ public:
+  static constexpr const bool value =
+      !std::is_void<decltype(check<T>(nullptr))>::value && !is_map<T>::value;
+};
+
+// C array overload
+template <typename T, std::size_t N>
+auto range_begin(const T (&arr)[N]) -> const T* {
+  return arr;
+}
+template <typename T, std::size_t N>
+auto range_end(const T (&arr)[N]) -> const T* {
+  return arr + N;
+}
+
+template <typename T, typename Enable = void>
+struct has_member_fn_begin_end_t : std::false_type {};
+
+template <typename T>
+struct has_member_fn_begin_end_t<T, void_t<decltype(*std::declval<T>().begin()),
+                                           decltype(std::declval<T>().end())>>
+    : std::true_type {};
+
+// Member function overloads.
+template <typename T>
+auto range_begin(T&& rng) -> decltype(static_cast<T&&>(rng).begin()) {
+  return static_cast<T&&>(rng).begin();
+}
+template <typename T>
+auto range_end(T&& rng) -> decltype(static_cast<T&&>(rng).end()) {
+  return static_cast<T&&>(rng).end();
+}
+
+// ADL overloads. Only participate in overload resolution if member functions
+// are not found.
+template <typename T>
+auto range_begin(T&& rng)
+    -> enable_if_t<!has_member_fn_begin_end_t<T&&>::value,
+                   decltype(begin(static_cast<T&&>(rng)))> {
+  return begin(static_cast<T&&>(rng));
+}
+template <typename T>
+auto range_end(T&& rng) -> enable_if_t<!has_member_fn_begin_end_t<T&&>::value,
+                                       decltype(end(static_cast<T&&>(rng)))> {
+  return end(static_cast<T&&>(rng));
+}
+
+template <typename T, typename Enable = void>
+struct has_const_begin_end : std::false_type {};
+template <typename T, typename Enable = void>
+struct has_mutable_begin_end : std::false_type {};
+
+template <typename T>
+struct has_const_begin_end<
+    T, void_t<decltype(*detail::range_begin(
+                  std::declval<const remove_cvref_t<T>&>())),
+              decltype(detail::range_end(
+                  std::declval<const remove_cvref_t<T>&>()))>>
+    : std::true_type {};
+
+template <typename T>
+struct has_mutable_begin_end<
+    T, void_t<decltype(*detail::range_begin(std::declval<T&>())),
+              decltype(detail::range_end(std::declval<T&>())),
+              // the extra int here is because older versions of MSVC don't
+              // SFINAE properly unless there are distinct types
+              int>> : std::true_type {};
+
+template <typename T, typename _ = void> struct is_range_ : std::false_type {};
+template <typename T>
+struct is_range_<T, void>
+    : std::integral_constant<bool, (has_const_begin_end<T>::value ||
+                                    has_mutable_begin_end<T>::value)> {};
+
+// tuple_size and tuple_element check.
+template <typename T> class is_tuple_like_ {
+  template <typename U, typename V = typename std::remove_cv<U>::type>
+  static auto check(U* p) -> decltype(std::tuple_size<V>::value, 0);
+  template <typename> static void check(...);
+
+ public:
+  static constexpr const bool value =
+      !std::is_void<decltype(check<T>(nullptr))>::value;
+};
+
+// Check for integer_sequence
+#if defined(__cpp_lib_integer_sequence) || FMT_MSC_VERSION >= 1900
+template <typename T, T... N>
+using integer_sequence = std::integer_sequence<T, N...>;
+template <size_t... N> using index_sequence = std::index_sequence<N...>;
+template <size_t N> using make_index_sequence = std::make_index_sequence<N>;
+#else
+template <typename T, T... N> struct integer_sequence {
+  using value_type = T;
+
+  static FMT_CONSTEXPR auto size() -> size_t { return sizeof...(N); }
+};
+
+template <size_t... N> using index_sequence = integer_sequence<size_t, N...>;
+
+template <typename T, size_t N, T... Ns>
+struct make_integer_sequence : make_integer_sequence<T, N - 1, N - 1, Ns...> {};
+template <typename T, T... Ns>
+struct make_integer_sequence<T, 0, Ns...> : integer_sequence<T, Ns...> {};
+
+template <size_t N>
+using make_index_sequence = make_integer_sequence<size_t, N>;
+#endif
+
+template <typename T>
+using tuple_index_sequence = make_index_sequence<std::tuple_size<T>::value>;
+
+template <typename T, typename C, bool = is_tuple_like_<T>::value>
+class is_tuple_formattable_ {
+ public:
+  static constexpr const bool value = false;
+};
+template <typename T, typename C> class is_tuple_formattable_<T, C, true> {
+  template <size_t... Is>
+  static auto all_true(index_sequence<Is...>,
+                       integer_sequence<bool, (Is >= 0)...>) -> std::true_type;
+  static auto all_true(...) -> std::false_type;
+
+  template <size_t... Is>
+  static auto check(index_sequence<Is...>) -> decltype(all_true(
+      index_sequence<Is...>{},
+      integer_sequence<bool,
+                       (is_formattable<typename std::tuple_element<Is, T>::type,
+                                       C>::value)...>{}));
+
+ public:
+  static constexpr const bool value =
+      decltype(check(tuple_index_sequence<T>{}))::value;
+};
+
+template <typename Tuple, typename F, size_t... Is>
+FMT_CONSTEXPR void for_each(index_sequence<Is...>, Tuple&& t, F&& f) {
+  using std::get;
+  // Using a free function get<Is>(Tuple) now.
+  const int unused[] = {0, ((void)f(get<Is>(t)), 0)...};
+  ignore_unused(unused);
+}
+
+template <typename Tuple, typename F>
+FMT_CONSTEXPR void for_each(Tuple&& t, F&& f) {
+  for_each(tuple_index_sequence<remove_cvref_t<Tuple>>(),
+           std::forward<Tuple>(t), std::forward<F>(f));
+}
+
+template <typename Tuple1, typename Tuple2, typename F, size_t... Is>
+void for_each2(index_sequence<Is...>, Tuple1&& t1, Tuple2&& t2, F&& f) {
+  using std::get;
+  const int unused[] = {0, ((void)f(get<Is>(t1), get<Is>(t2)), 0)...};
+  ignore_unused(unused);
+}
+
+template <typename Tuple1, typename Tuple2, typename F>
+void for_each2(Tuple1&& t1, Tuple2&& t2, F&& f) {
+  for_each2(tuple_index_sequence<remove_cvref_t<Tuple1>>(),
+            std::forward<Tuple1>(t1), std::forward<Tuple2>(t2),
+            std::forward<F>(f));
+}
+
+namespace tuple {
+// Workaround a bug in MSVC 2019 (v140).
+template <typename Char, typename... T>
+using result_t = std::tuple<formatter<remove_cvref_t<T>, Char>...>;
+
+using std::get;
+template <typename Tuple, typename Char, std::size_t... Is>
+auto get_formatters(index_sequence<Is...>)
+    -> result_t<Char, decltype(get<Is>(std::declval<Tuple>()))...>;
+}  // namespace tuple
+
+#if FMT_MSC_VERSION && FMT_MSC_VERSION < 1920
+// Older MSVC doesn't get the reference type correctly for arrays.
+template <typename R> struct range_reference_type_impl {
+  using type = decltype(*detail::range_begin(std::declval<R&>()));
+};
+
+template <typename T, std::size_t N> struct range_reference_type_impl<T[N]> {
+  using type = T&;
+};
+
+template <typename T>
+using range_reference_type = typename range_reference_type_impl<T>::type;
+#else
+template <typename Range>
+using range_reference_type =
+    decltype(*detail::range_begin(std::declval<Range&>()));
+#endif
+
+// We don't use the Range's value_type for anything, but we do need the Range's
+// reference type, with cv-ref stripped.
+template <typename Range>
+using uncvref_type = remove_cvref_t<range_reference_type<Range>>;
+
+template <typename Formatter>
+FMT_CONSTEXPR auto maybe_set_debug_format(Formatter& f, bool set)
+    -> decltype(f.set_debug_format(set)) {
+  f.set_debug_format(set);
+}
+template <typename Formatter>
+FMT_CONSTEXPR void maybe_set_debug_format(Formatter&, ...) {}
+
+template <typename T>
+struct range_format_kind_
+    : std::integral_constant<range_format,
+                             std::is_same<uncvref_type<T>, T>::value
+                                 ? range_format::disabled
+                             : is_map<T>::value ? range_format::map
+                             : is_set<T>::value ? range_format::set
+                                                : range_format::sequence> {};
+
+template <range_format K>
+using range_format_constant = std::integral_constant<range_format, K>;
+
+// These are not generic lambdas for compatibility with C++11.
+template <typename Char> struct parse_empty_specs {
+  template <typename Formatter> FMT_CONSTEXPR void operator()(Formatter& f) {
+    f.parse(ctx);
+    detail::maybe_set_debug_format(f, true);
+  }
+  parse_context<Char>& ctx;
+};
+template <typename FormatContext> struct format_tuple_element {
+  using char_type = typename FormatContext::char_type;
+
+  template <typename T>
+  void operator()(const formatter<T, char_type>& f, const T& v) {
+    if (i > 0) ctx.advance_to(detail::copy<char_type>(separator, ctx.out()));
+    ctx.advance_to(f.format(v, ctx));
+    ++i;
+  }
+
+  int i;
+  FormatContext& ctx;
+  basic_string_view<char_type> separator;
+};
+
+}  // namespace detail
+
+template <typename T> struct is_tuple_like {
+  static constexpr const bool value =
+      detail::is_tuple_like_<T>::value && !detail::is_range_<T>::value;
+};
+
+template <typename T, typename C> struct is_tuple_formattable {
+  static constexpr const bool value =
+      detail::is_tuple_formattable_<T, C>::value;
+};
+
+template <typename Tuple, typename Char>
+struct formatter<Tuple, Char,
+                 enable_if_t<fmt::is_tuple_like<Tuple>::value &&
+                             fmt::is_tuple_formattable<Tuple, Char>::value>> {
+ private:
+  decltype(detail::tuple::get_formatters<Tuple, Char>(
+      detail::tuple_index_sequence<Tuple>())) formatters_;
+
+  basic_string_view<Char> separator_ = detail::string_literal<Char, ',', ' '>{};
+  basic_string_view<Char> opening_bracket_ =
+      detail::string_literal<Char, '('>{};
+  basic_string_view<Char> closing_bracket_ =
+      detail::string_literal<Char, ')'>{};
+
+ public:
+  FMT_CONSTEXPR formatter() {}
+
+  FMT_CONSTEXPR void set_separator(basic_string_view<Char> sep) {
+    separator_ = sep;
+  }
+
+  FMT_CONSTEXPR void set_brackets(basic_string_view<Char> open,
+                                  basic_string_view<Char> close) {
+    opening_bracket_ = open;
+    closing_bracket_ = close;
+  }
+
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    auto it = ctx.begin();
+    auto end = ctx.end();
+    if (it != end && detail::to_ascii(*it) == 'n') {
+      ++it;
+      set_brackets({}, {});
+      set_separator({});
+    }
+    if (it != end && *it != '}') report_error("invalid format specifier");
+    ctx.advance_to(it);
+    detail::for_each(formatters_, detail::parse_empty_specs<Char>{ctx});
+    return it;
+  }
+
+  template <typename FormatContext>
+  auto format(const Tuple& value, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    ctx.advance_to(detail::copy<Char>(opening_bracket_, ctx.out()));
+    detail::for_each2(
+        formatters_, value,
+        detail::format_tuple_element<FormatContext>{0, ctx, separator_});
+    return detail::copy<Char>(closing_bracket_, ctx.out());
+  }
+};
+
+template <typename T, typename Char> struct is_range {
+  static constexpr const bool value =
+      detail::is_range_<T>::value && !detail::has_to_string_view<T>::value;
+};
+
+namespace detail {
+
+template <typename Char, typename Element>
+using range_formatter_type = formatter<remove_cvref_t<Element>, Char>;
+
+template <typename R>
+using maybe_const_range =
+    conditional_t<has_const_begin_end<R>::value, const R, R>;
+
+template <typename R, typename Char>
+struct is_formattable_delayed
+    : is_formattable<uncvref_type<maybe_const_range<R>>, Char> {};
+}  // namespace detail
+
+template <typename...> struct conjunction : std::true_type {};
+template <typename P> struct conjunction<P> : P {};
+template <typename P1, typename... Pn>
+struct conjunction<P1, Pn...>
+    : conditional_t<bool(P1::value), conjunction<Pn...>, P1> {};
+
+template <typename T, typename Char, typename Enable = void>
+struct range_formatter;
+
+template <typename T, typename Char>
+struct range_formatter<
+    T, Char,
+    enable_if_t<conjunction<std::is_same<T, remove_cvref_t<T>>,
+                            is_formattable<T, Char>>::value>> {
+ private:
+  detail::range_formatter_type<Char, T> underlying_;
+  basic_string_view<Char> separator_ = detail::string_literal<Char, ',', ' '>{};
+  basic_string_view<Char> opening_bracket_ =
+      detail::string_literal<Char, '['>{};
+  basic_string_view<Char> closing_bracket_ =
+      detail::string_literal<Char, ']'>{};
+  bool is_debug = false;
+
+  template <typename Output, typename It, typename Sentinel, typename U = T,
+            FMT_ENABLE_IF(std::is_same<U, Char>::value)>
+  auto write_debug_string(Output& out, It it, Sentinel end) const -> Output {
+    auto buf = basic_memory_buffer<Char>();
+    for (; it != end; ++it) buf.push_back(*it);
+    auto specs = format_specs();
+    specs.set_type(presentation_type::debug);
+    return detail::write<Char>(
+        out, basic_string_view<Char>(buf.data(), buf.size()), specs);
+  }
+
+  template <typename Output, typename It, typename Sentinel, typename U = T,
+            FMT_ENABLE_IF(!std::is_same<U, Char>::value)>
+  auto write_debug_string(Output& out, It, Sentinel) const -> Output {
+    return out;
+  }
+
+ public:
+  FMT_CONSTEXPR range_formatter() {}
+
+  FMT_CONSTEXPR auto underlying() -> detail::range_formatter_type<Char, T>& {
+    return underlying_;
+  }
+
+  FMT_CONSTEXPR void set_separator(basic_string_view<Char> sep) {
+    separator_ = sep;
+  }
+
+  FMT_CONSTEXPR void set_brackets(basic_string_view<Char> open,
+                                  basic_string_view<Char> close) {
+    opening_bracket_ = open;
+    closing_bracket_ = close;
+  }
+
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    auto it = ctx.begin();
+    auto end = ctx.end();
+    detail::maybe_set_debug_format(underlying_, true);
+    if (it == end) return underlying_.parse(ctx);
+
+    switch (detail::to_ascii(*it)) {
+    case 'n':
+      set_brackets({}, {});
+      ++it;
+      break;
+    case '?':
+      is_debug = true;
+      set_brackets({}, {});
+      ++it;
+      if (it == end || *it != 's') report_error("invalid format specifier");
+      FMT_FALLTHROUGH;
+    case 's':
+      if (!std::is_same<T, Char>::value)
+        report_error("invalid format specifier");
+      if (!is_debug) {
+        set_brackets(detail::string_literal<Char, '"'>{},
+                     detail::string_literal<Char, '"'>{});
+        set_separator({});
+        detail::maybe_set_debug_format(underlying_, false);
+      }
+      ++it;
+      return it;
+    }
+
+    if (it != end && *it != '}') {
+      if (*it != ':') report_error("invalid format specifier");
+      detail::maybe_set_debug_format(underlying_, false);
+      ++it;
+    }
+
+    ctx.advance_to(it);
+    return underlying_.parse(ctx);
+  }
+
+  template <typename R, typename FormatContext>
+  auto format(R&& range, FormatContext& ctx) const -> decltype(ctx.out()) {
+    auto out = ctx.out();
+    auto it = detail::range_begin(range);
+    auto end = detail::range_end(range);
+    if (is_debug) return write_debug_string(out, std::move(it), end);
+
+    out = detail::copy<Char>(opening_bracket_, out);
+    int i = 0;
+    for (; it != end; ++it) {
+      if (i > 0) out = detail::copy<Char>(separator_, out);
+      ctx.advance_to(out);
+      auto&& item = *it;  // Need an lvalue
+      out = underlying_.format(item, ctx);
+      ++i;
+    }
+    out = detail::copy<Char>(closing_bracket_, out);
+    return out;
+  }
+};
+
+FMT_EXPORT
+template <typename T, typename Char, typename Enable = void>
+struct range_format_kind
+    : conditional_t<
+          is_range<T, Char>::value, detail::range_format_kind_<T>,
+          std::integral_constant<range_format, range_format::disabled>> {};
+
+template <typename R, typename Char>
+struct formatter<
+    R, Char,
+    enable_if_t<conjunction<
+        bool_constant<
+            range_format_kind<R, Char>::value != range_format::disabled &&
+            range_format_kind<R, Char>::value != range_format::map &&
+            range_format_kind<R, Char>::value != range_format::string &&
+            range_format_kind<R, Char>::value != range_format::debug_string>,
+        detail::is_formattable_delayed<R, Char>>::value>> {
+ private:
+  using range_type = detail::maybe_const_range<R>;
+  range_formatter<detail::uncvref_type<range_type>, Char> range_formatter_;
+
+ public:
+  using nonlocking = void;
+
+  FMT_CONSTEXPR formatter() {
+    if (detail::const_check(range_format_kind<R, Char>::value !=
+                            range_format::set))
+      return;
+    range_formatter_.set_brackets(detail::string_literal<Char, '{'>{},
+                                  detail::string_literal<Char, '}'>{});
+  }
+
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return range_formatter_.parse(ctx);
+  }
+
+  template <typename FormatContext>
+  auto format(range_type& range, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return range_formatter_.format(range, ctx);
+  }
+};
+
+// A map formatter.
+template <typename R, typename Char>
+struct formatter<
+    R, Char,
+    enable_if_t<range_format_kind<R, Char>::value == range_format::map>> {
+ private:
+  using map_type = detail::maybe_const_range<R>;
+  using element_type = detail::uncvref_type<map_type>;
+
+  decltype(detail::tuple::get_formatters<element_type, Char>(
+      detail::tuple_index_sequence<element_type>())) formatters_;
+  bool no_delimiters_ = false;
+
+ public:
+  FMT_CONSTEXPR formatter() {}
+
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    auto it = ctx.begin();
+    auto end = ctx.end();
+    if (it != end) {
+      if (detail::to_ascii(*it) == 'n') {
+        no_delimiters_ = true;
+        ++it;
+      }
+      if (it != end && *it != '}') {
+        if (*it != ':') report_error("invalid format specifier");
+        ++it;
+      }
+      ctx.advance_to(it);
+    }
+    detail::for_each(formatters_, detail::parse_empty_specs<Char>{ctx});
+    return it;
+  }
+
+  template <typename FormatContext>
+  auto format(map_type& map, FormatContext& ctx) const -> decltype(ctx.out()) {
+    auto out = ctx.out();
+    basic_string_view<Char> open = detail::string_literal<Char, '{'>{};
+    if (!no_delimiters_) out = detail::copy<Char>(open, out);
+    int i = 0;
+    basic_string_view<Char> sep = detail::string_literal<Char, ',', ' '>{};
+    for (auto&& value : map) {
+      if (i > 0) out = detail::copy<Char>(sep, out);
+      ctx.advance_to(out);
+      detail::for_each2(formatters_, value,
+                        detail::format_tuple_element<FormatContext>{
+                            0, ctx, detail::string_literal<Char, ':', ' '>{}});
+      ++i;
+    }
+    basic_string_view<Char> close = detail::string_literal<Char, '}'>{};
+    if (!no_delimiters_) out = detail::copy<Char>(close, out);
+    return out;
+  }
+};
+
+// A (debug_)string formatter.
+template <typename R, typename Char>
+struct formatter<
+    R, Char,
+    enable_if_t<range_format_kind<R, Char>::value == range_format::string ||
+                range_format_kind<R, Char>::value ==
+                    range_format::debug_string>> {
+ private:
+  using range_type = detail::maybe_const_range<R>;
+  using string_type =
+      conditional_t<std::is_constructible<
+                        detail::std_string_view<Char>,
+                        decltype(detail::range_begin(std::declval<R>())),
+                        decltype(detail::range_end(std::declval<R>()))>::value,
+                    detail::std_string_view<Char>, std::basic_string<Char>>;
+
+  formatter<string_type, Char> underlying_;
+
+ public:
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return underlying_.parse(ctx);
+  }
+
+  template <typename FormatContext>
+  auto format(range_type& range, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+    if (detail::const_check(range_format_kind<R, Char>::value ==
+                            range_format::debug_string))
+      *out++ = '"';
+    out = underlying_.format(
+        string_type{detail::range_begin(range), detail::range_end(range)}, ctx);
+    if (detail::const_check(range_format_kind<R, Char>::value ==
+                            range_format::debug_string))
+      *out++ = '"';
+    return out;
+  }
+};
+
+template <typename It, typename Sentinel, typename Char = char>
+struct join_view : detail::view {
+  It begin;
+  Sentinel end;
+  basic_string_view<Char> sep;
+
+  join_view(It b, Sentinel e, basic_string_view<Char> s)
+      : begin(std::move(b)), end(e), sep(s) {}
+};
+
+template <typename It, typename Sentinel, typename Char>
+struct formatter<join_view<It, Sentinel, Char>, Char> {
+ private:
+  using value_type =
+#ifdef __cpp_lib_ranges
+      std::iter_value_t<It>;
+#else
+      typename std::iterator_traits<It>::value_type;
+#endif
+  formatter<remove_cvref_t<value_type>, Char> value_formatter_;
+
+  using view = conditional_t<std::is_copy_constructible<It>::value,
+                             const join_view<It, Sentinel, Char>,
+                             join_view<It, Sentinel, Char>>;
+
+ public:
+  using nonlocking = void;
+
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return value_formatter_.parse(ctx);
+  }
+
+  template <typename FormatContext>
+  auto format(view& value, FormatContext& ctx) const -> decltype(ctx.out()) {
+    using iter =
+        conditional_t<std::is_copy_constructible<view>::value, It, It&>;
+    iter it = value.begin;
+    auto out = ctx.out();
+    if (it == value.end) return out;
+    out = value_formatter_.format(*it, ctx);
+    ++it;
+    while (it != value.end) {
+      out = detail::copy<Char>(value.sep.begin(), value.sep.end(), out);
+      ctx.advance_to(out);
+      out = value_formatter_.format(*it, ctx);
+      ++it;
+    }
+    return out;
+  }
+};
+
+template <typename Char, typename Tuple> struct tuple_join_view : detail::view {
+  const Tuple& tuple;
+  basic_string_view<Char> sep;
+
+  tuple_join_view(const Tuple& t, basic_string_view<Char> s)
+      : tuple(t), sep{s} {}
+};
+
+// Define FMT_TUPLE_JOIN_SPECIFIERS to enable experimental format specifiers
+// support in tuple_join. It is disabled by default because of issues with
+// the dynamic width and precision.
+#ifndef FMT_TUPLE_JOIN_SPECIFIERS
+#  define FMT_TUPLE_JOIN_SPECIFIERS 0
+#endif
+
+template <typename Char, typename Tuple>
+struct formatter<tuple_join_view<Char, Tuple>, Char,
+                 enable_if_t<is_tuple_like<Tuple>::value>> {
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return do_parse(ctx, std::tuple_size<Tuple>());
+  }
+
+  template <typename FormatContext>
+  auto format(const tuple_join_view<Char, Tuple>& value,
+              FormatContext& ctx) const -> typename FormatContext::iterator {
+    return do_format(value, ctx, std::tuple_size<Tuple>());
+  }
+
+ private:
+  decltype(detail::tuple::get_formatters<Tuple, Char>(
+      detail::tuple_index_sequence<Tuple>())) formatters_;
+
+  FMT_CONSTEXPR auto do_parse(parse_context<Char>& ctx,
+                              std::integral_constant<size_t, 0>)
+      -> const Char* {
+    return ctx.begin();
+  }
+
+  template <size_t N>
+  FMT_CONSTEXPR auto do_parse(parse_context<Char>& ctx,
+                              std::integral_constant<size_t, N>)
+      -> const Char* {
+    auto end = ctx.begin();
+#if FMT_TUPLE_JOIN_SPECIFIERS
+    end = std::get<std::tuple_size<Tuple>::value - N>(formatters_).parse(ctx);
+    if (N > 1) {
+      auto end1 = do_parse(ctx, std::integral_constant<size_t, N - 1>());
+      if (end != end1)
+        report_error("incompatible format specs for tuple elements");
+    }
+#endif
+    return end;
+  }
+
+  template <typename FormatContext>
+  auto do_format(const tuple_join_view<Char, Tuple>&, FormatContext& ctx,
+                 std::integral_constant<size_t, 0>) const ->
+      typename FormatContext::iterator {
+    return ctx.out();
+  }
+
+  template <typename FormatContext, size_t N>
+  auto do_format(const tuple_join_view<Char, Tuple>& value, FormatContext& ctx,
+                 std::integral_constant<size_t, N>) const ->
+      typename FormatContext::iterator {
+    using std::get;
+    auto out =
+        std::get<std::tuple_size<Tuple>::value - N>(formatters_)
+            .format(get<std::tuple_size<Tuple>::value - N>(value.tuple), ctx);
+    if (N <= 1) return out;
+    out = detail::copy<Char>(value.sep, out);
+    ctx.advance_to(out);
+    return do_format(value, ctx, std::integral_constant<size_t, N - 1>());
+  }
+};
+
+namespace detail {
+// Check if T has an interface like a container adaptor (e.g. std::stack,
+// std::queue, std::priority_queue).
+template <typename T> class is_container_adaptor_like {
+  template <typename U> static auto check(U* p) -> typename U::container_type;
+  template <typename> static void check(...);
+
+ public:
+  static constexpr const bool value =
+      !std::is_void<decltype(check<T>(nullptr))>::value;
+};
+
+template <typename Container> struct all {
+  const Container& c;
+  auto begin() const -> typename Container::const_iterator { return c.begin(); }
+  auto end() const -> typename Container::const_iterator { return c.end(); }
+};
+}  // namespace detail
+
+template <typename T, typename Char>
+struct formatter<
+    T, Char,
+    enable_if_t<conjunction<detail::is_container_adaptor_like<T>,
+                            bool_constant<range_format_kind<T, Char>::value ==
+                                          range_format::disabled>>::value>>
+    : formatter<detail::all<typename T::container_type>, Char> {
+  using all = detail::all<typename T::container_type>;
+  template <typename FormatContext>
+  auto format(const T& t, FormatContext& ctx) const -> decltype(ctx.out()) {
+    struct getter : T {
+      static auto get(const T& t) -> all {
+        return {t.*(&getter::c)};  // Access c through the derived class.
+      }
+    };
+    return formatter<all>::format(getter::get(t), ctx);
+  }
+};
+
+FMT_BEGIN_EXPORT
+
+/// Returns a view that formats the iterator range `[begin, end)` with elements
+/// separated by `sep`.
+template <typename It, typename Sentinel>
+auto join(It begin, Sentinel end, string_view sep) -> join_view<It, Sentinel> {
+  return {std::move(begin), end, sep};
+}
+
+/**
+ * Returns a view that formats `range` with elements separated by `sep`.
+ *
+ * **Example**:
+ *
+ *     auto v = std::vector<int>{1, 2, 3};
+ *     fmt::print("{}", fmt::join(v, ", "));
+ *     // Output: 1, 2, 3
+ *
+ * `fmt::join` applies passed format specifiers to the range elements:
+ *
+ *     fmt::print("{:02}", fmt::join(v, ", "));
+ *     // Output: 01, 02, 03
+ */
+template <typename Range, FMT_ENABLE_IF(!is_tuple_like<Range>::value)>
+auto join(Range&& r, string_view sep)
+    -> join_view<decltype(detail::range_begin(r)),
+                 decltype(detail::range_end(r))> {
+  return {detail::range_begin(r), detail::range_end(r), sep};
+}
+
+/**
+ * Returns an object that formats `std::tuple` with elements separated by `sep`.
+ *
+ * **Example**:
+ *
+ *     auto t = std::tuple<int, char>{1, 'a'};
+ *     fmt::print("{}", fmt::join(t, ", "));
+ *     // Output: 1, a
+ */
+template <typename Tuple, FMT_ENABLE_IF(is_tuple_like<Tuple>::value)>
+FMT_CONSTEXPR auto join(const Tuple& tuple, string_view sep)
+    -> tuple_join_view<char, Tuple> {
+  return {tuple, sep};
+}
+
+/**
+ * Returns an object that formats `std::initializer_list` with elements
+ * separated by `sep`.
+ *
+ * **Example**:
+ *
+ *     fmt::print("{}", fmt::join({1, 2, 3}, ", "));
+ *     // Output: "1, 2, 3"
+ */
+template <typename T>
+auto join(std::initializer_list<T> list, string_view sep)
+    -> join_view<const T*, const T*> {
+  return join(std::begin(list), std::end(list), sep);
+}
+
+FMT_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_RANGES_H_

extlib/libfmt/include/fmt/std.h

@@ -0,0 +1,726 @@
+// Formatting library for C++ - formatters for standard library types
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_STD_H_
+#define FMT_STD_H_
+
+#include "format.h"
+#include "ostream.h"
+
+#ifndef FMT_MODULE
+#  include <atomic>
+#  include <bitset>
+#  include <complex>
+#  include <cstdlib>
+#  include <exception>
+#  include <functional>
+#  include <memory>
+#  include <thread>
+#  include <type_traits>
+#  include <typeinfo>
+#  include <utility>
+#  include <vector>
+
+// Check FMT_CPLUSPLUS to suppress a bogus warning in MSVC.
+#  if FMT_CPLUSPLUS >= 201703L
+#    if FMT_HAS_INCLUDE(<filesystem>) && \
+        (!defined(FMT_CPP_LIB_FILESYSTEM) || FMT_CPP_LIB_FILESYSTEM != 0)
+#      include <filesystem>
+#    endif
+#    if FMT_HAS_INCLUDE(<variant>)
+#      include <variant>
+#    endif
+#    if FMT_HAS_INCLUDE(<optional>)
+#      include <optional>
+#    endif
+#  endif
+// Use > instead of >= in the version check because <source_location> may be
+// available after C++17 but before C++20 is marked as implemented.
+#  if FMT_CPLUSPLUS > 201703L && FMT_HAS_INCLUDE(<source_location>)
+#    include <source_location>
+#  endif
+#  if FMT_CPLUSPLUS > 202002L && FMT_HAS_INCLUDE(<expected>)
+#    include <expected>
+#  endif
+#endif  // FMT_MODULE
+
+#if FMT_HAS_INCLUDE(<version>)
+#  include <version>
+#endif
+
+// GCC 4 does not support FMT_HAS_INCLUDE.
+#if FMT_HAS_INCLUDE(<cxxabi.h>) || defined(__GLIBCXX__)
+#  include <cxxabi.h>
+// Android NDK with gabi++ library on some architectures does not implement
+// abi::__cxa_demangle().
+#  ifndef __GABIXX_CXXABI_H__
+#    define FMT_HAS_ABI_CXA_DEMANGLE
+#  endif
+#endif
+
+// For older Xcode versions, __cpp_lib_xxx flags are inaccurately defined.
+#ifndef FMT_CPP_LIB_FILESYSTEM
+#  ifdef __cpp_lib_filesystem
+#    define FMT_CPP_LIB_FILESYSTEM __cpp_lib_filesystem
+#  else
+#    define FMT_CPP_LIB_FILESYSTEM 0
+#  endif
+#endif
+
+#ifndef FMT_CPP_LIB_VARIANT
+#  ifdef __cpp_lib_variant
+#    define FMT_CPP_LIB_VARIANT __cpp_lib_variant
+#  else
+#    define FMT_CPP_LIB_VARIANT 0
+#  endif
+#endif
+
+#if FMT_CPP_LIB_FILESYSTEM
+FMT_BEGIN_NAMESPACE
+
+namespace detail {
+
+template <typename Char, typename PathChar>
+auto get_path_string(const std::filesystem::path& p,
+                     const std::basic_string<PathChar>& native) {
+  if constexpr (std::is_same_v<Char, char> && std::is_same_v<PathChar, wchar_t>)
+    return to_utf8<wchar_t>(native, to_utf8_error_policy::replace);
+  else
+    return p.string<Char>();
+}
+
+template <typename Char, typename PathChar>
+void write_escaped_path(basic_memory_buffer<Char>& quoted,
+                        const std::filesystem::path& p,
+                        const std::basic_string<PathChar>& native) {
+  if constexpr (std::is_same_v<Char, char> &&
+                std::is_same_v<PathChar, wchar_t>) {
+    auto buf = basic_memory_buffer<wchar_t>();
+    write_escaped_string<wchar_t>(std::back_inserter(buf), native);
+    bool valid = to_utf8<wchar_t>::convert(quoted, {buf.data(), buf.size()});
+    FMT_ASSERT(valid, "invalid utf16");
+  } else if constexpr (std::is_same_v<Char, PathChar>) {
+    write_escaped_string<std::filesystem::path::value_type>(
+        std::back_inserter(quoted), native);
+  } else {
+    write_escaped_string<Char>(std::back_inserter(quoted), p.string<Char>());
+  }
+}
+
+}  // namespace detail
+
+FMT_EXPORT
+template <typename Char> struct formatter<std::filesystem::path, Char> {
+ private:
+  format_specs specs_;
+  detail::arg_ref<Char> width_ref_;
+  bool debug_ = false;
+  char path_type_ = 0;
+
+ public:
+  FMT_CONSTEXPR void set_debug_format(bool set = true) { debug_ = set; }
+
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) {
+    auto it = ctx.begin(), end = ctx.end();
+    if (it == end) return it;
+
+    it = detail::parse_align(it, end, specs_);
+    if (it == end) return it;
+
+    Char c = *it;
+    if ((c >= '0' && c <= '9') || c == '{')
+      it = detail::parse_width(it, end, specs_, width_ref_, ctx);
+    if (it != end && *it == '?') {
+      debug_ = true;
+      ++it;
+    }
+    if (it != end && (*it == 'g')) path_type_ = detail::to_ascii(*it++);
+    return it;
+  }
+
+  template <typename FormatContext>
+  auto format(const std::filesystem::path& p, FormatContext& ctx) const {
+    auto specs = specs_;
+    auto path_string =
+        !path_type_ ? p.native()
+                    : p.generic_string<std::filesystem::path::value_type>();
+
+    detail::handle_dynamic_spec(specs.dynamic_width(), specs.width, width_ref_,
+                                ctx);
+    if (!debug_) {
+      auto s = detail::get_path_string<Char>(p, path_string);
+      return detail::write(ctx.out(), basic_string_view<Char>(s), specs);
+    }
+    auto quoted = basic_memory_buffer<Char>();
+    detail::write_escaped_path(quoted, p, path_string);
+    return detail::write(ctx.out(),
+                         basic_string_view<Char>(quoted.data(), quoted.size()),
+                         specs);
+  }
+};
+
+class path : public std::filesystem::path {
+ public:
+  auto display_string() const -> std::string {
+    const std::filesystem::path& base = *this;
+    return fmt::format(FMT_STRING("{}"), base);
+  }
+  auto system_string() const -> std::string { return string(); }
+
+  auto generic_display_string() const -> std::string {
+    const std::filesystem::path& base = *this;
+    return fmt::format(FMT_STRING("{:g}"), base);
+  }
+  auto generic_system_string() const -> std::string { return generic_string(); }
+};
+
+FMT_END_NAMESPACE
+#endif  // FMT_CPP_LIB_FILESYSTEM
+
+FMT_BEGIN_NAMESPACE
+FMT_EXPORT
+template <std::size_t N, typename Char>
+struct formatter<std::bitset<N>, Char>
+    : nested_formatter<basic_string_view<Char>, Char> {
+ private:
+  // Functor because C++11 doesn't support generic lambdas.
+  struct writer {
+    const std::bitset<N>& bs;
+
+    template <typename OutputIt>
+    FMT_CONSTEXPR auto operator()(OutputIt out) -> OutputIt {
+      for (auto pos = N; pos > 0; --pos) {
+        out = detail::write<Char>(out, bs[pos - 1] ? Char('1') : Char('0'));
+      }
+
+      return out;
+    }
+  };
+
+ public:
+  template <typename FormatContext>
+  auto format(const std::bitset<N>& bs, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return this->write_padded(ctx, writer{bs});
+  }
+};
+
+FMT_EXPORT
+template <typename Char>
+struct formatter<std::thread::id, Char> : basic_ostream_formatter<Char> {};
+FMT_END_NAMESPACE
+
+#ifdef __cpp_lib_optional
+FMT_BEGIN_NAMESPACE
+FMT_EXPORT
+template <typename T, typename Char>
+struct formatter<std::optional<T>, Char,
+                 std::enable_if_t<is_formattable<T, Char>::value>> {
+ private:
+  formatter<T, Char> underlying_;
+  static constexpr basic_string_view<Char> optional =
+      detail::string_literal<Char, 'o', 'p', 't', 'i', 'o', 'n', 'a', 'l',
+                             '('>{};
+  static constexpr basic_string_view<Char> none =
+      detail::string_literal<Char, 'n', 'o', 'n', 'e'>{};
+
+  template <class U>
+  FMT_CONSTEXPR static auto maybe_set_debug_format(U& u, bool set)
+      -> decltype(u.set_debug_format(set)) {
+    u.set_debug_format(set);
+  }
+
+  template <class U>
+  FMT_CONSTEXPR static void maybe_set_debug_format(U&, ...) {}
+
+ public:
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) {
+    maybe_set_debug_format(underlying_, true);
+    return underlying_.parse(ctx);
+  }
+
+  template <typename FormatContext>
+  auto format(const std::optional<T>& opt, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    if (!opt) return detail::write<Char>(ctx.out(), none);
+
+    auto out = ctx.out();
+    out = detail::write<Char>(out, optional);
+    ctx.advance_to(out);
+    out = underlying_.format(*opt, ctx);
+    return detail::write(out, ')');
+  }
+};
+FMT_END_NAMESPACE
+#endif  // __cpp_lib_optional
+
+#if defined(__cpp_lib_expected) || FMT_CPP_LIB_VARIANT
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template <typename Char, typename OutputIt, typename T>
+auto write_escaped_alternative(OutputIt out, const T& v) -> OutputIt {
+  if constexpr (has_to_string_view<T>::value)
+    return write_escaped_string<Char>(out, detail::to_string_view(v));
+  if constexpr (std::is_same_v<T, Char>) return write_escaped_char(out, v);
+  return write<Char>(out, v);
+}
+
+}  // namespace detail
+
+FMT_END_NAMESPACE
+#endif
+
+#ifdef __cpp_lib_expected
+FMT_BEGIN_NAMESPACE
+
+FMT_EXPORT
+template <typename T, typename E, typename Char>
+struct formatter<std::expected<T, E>, Char,
+                 std::enable_if_t<(std::is_void<T>::value ||
+                                   is_formattable<T, Char>::value) &&
+                                  is_formattable<E, Char>::value>> {
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const std::expected<T, E>& value, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+
+    if (value.has_value()) {
+      out = detail::write<Char>(out, "expected(");
+      if constexpr (!std::is_void<T>::value)
+        out = detail::write_escaped_alternative<Char>(out, *value);
+    } else {
+      out = detail::write<Char>(out, "unexpected(");
+      out = detail::write_escaped_alternative<Char>(out, value.error());
+    }
+    *out++ = ')';
+    return out;
+  }
+};
+FMT_END_NAMESPACE
+#endif  // __cpp_lib_expected
+
+#ifdef __cpp_lib_source_location
+FMT_BEGIN_NAMESPACE
+FMT_EXPORT
+template <> struct formatter<std::source_location> {
+  FMT_CONSTEXPR auto parse(parse_context<>& ctx) { return ctx.begin(); }
+
+  template <typename FormatContext>
+  auto format(const std::source_location& loc, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+    out = detail::write(out, loc.file_name());
+    out = detail::write(out, ':');
+    out = detail::write<char>(out, loc.line());
+    out = detail::write(out, ':');
+    out = detail::write<char>(out, loc.column());
+    out = detail::write(out, ": ");
+    out = detail::write(out, loc.function_name());
+    return out;
+  }
+};
+FMT_END_NAMESPACE
+#endif
+
+#if FMT_CPP_LIB_VARIANT
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template <typename T>
+using variant_index_sequence =
+    std::make_index_sequence<std::variant_size<T>::value>;
+
+template <typename> struct is_variant_like_ : std::false_type {};
+template <typename... Types>
+struct is_variant_like_<std::variant<Types...>> : std::true_type {};
+
+// formattable element check.
+template <typename T, typename C> class is_variant_formattable_ {
+  template <std::size_t... Is>
+  static std::conjunction<
+      is_formattable<std::variant_alternative_t<Is, T>, C>...>
+      check(std::index_sequence<Is...>);
+
+ public:
+  static constexpr const bool value =
+      decltype(check(variant_index_sequence<T>{}))::value;
+};
+
+}  // namespace detail
+
+template <typename T> struct is_variant_like {
+  static constexpr const bool value = detail::is_variant_like_<T>::value;
+};
+
+template <typename T, typename C> struct is_variant_formattable {
+  static constexpr const bool value =
+      detail::is_variant_formattable_<T, C>::value;
+};
+
+FMT_EXPORT
+template <typename Char> struct formatter<std::monostate, Char> {
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const std::monostate&, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return detail::write<Char>(ctx.out(), "monostate");
+  }
+};
+
+FMT_EXPORT
+template <typename Variant, typename Char>
+struct formatter<
+    Variant, Char,
+    std::enable_if_t<std::conjunction_v<
+        is_variant_like<Variant>, is_variant_formattable<Variant, Char>>>> {
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const Variant& value, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+
+    out = detail::write<Char>(out, "variant(");
+    FMT_TRY {
+      std::visit(
+          [&](const auto& v) {
+            out = detail::write_escaped_alternative<Char>(out, v);
+          },
+          value);
+    }
+    FMT_CATCH(const std::bad_variant_access&) {
+      detail::write<Char>(out, "valueless by exception");
+    }
+    *out++ = ')';
+    return out;
+  }
+};
+FMT_END_NAMESPACE
+#endif  // FMT_CPP_LIB_VARIANT
+
+FMT_BEGIN_NAMESPACE
+FMT_EXPORT
+template <> struct formatter<std::error_code> {
+ private:
+  format_specs specs_;
+  detail::arg_ref<char> width_ref_;
+
+ public:
+  FMT_CONSTEXPR auto parse(parse_context<>& ctx) -> const char* {
+    auto it = ctx.begin(), end = ctx.end();
+    if (it == end) return it;
+
+    it = detail::parse_align(it, end, specs_);
+    if (it == end) return it;
+
+    char c = *it;
+    if ((c >= '0' && c <= '9') || c == '{')
+      it = detail::parse_width(it, end, specs_, width_ref_, ctx);
+    return it;
+  }
+
+  template <typename FormatContext>
+  FMT_CONSTEXPR20 auto format(const std::error_code& ec,
+                              FormatContext& ctx) const -> decltype(ctx.out()) {
+    auto specs = specs_;
+    detail::handle_dynamic_spec(specs.dynamic_width(), specs.width, width_ref_,
+                                ctx);
+    memory_buffer buf;
+    buf.append(string_view(ec.category().name()));
+    buf.push_back(':');
+    detail::write<char>(appender(buf), ec.value());
+    return detail::write<char>(ctx.out(), string_view(buf.data(), buf.size()),
+                               specs);
+  }
+};
+
+#if FMT_USE_RTTI
+namespace detail {
+
+template <typename Char, typename OutputIt>
+auto write_demangled_name(OutputIt out, const std::type_info& ti) -> OutputIt {
+#  ifdef FMT_HAS_ABI_CXA_DEMANGLE
+  int status = 0;
+  std::size_t size = 0;
+  std::unique_ptr<char, void (*)(void*)> demangled_name_ptr(
+      abi::__cxa_demangle(ti.name(), nullptr, &size, &status), &std::free);
+
+  string_view demangled_name_view;
+  if (demangled_name_ptr) {
+    demangled_name_view = demangled_name_ptr.get();
+
+    // Normalization of stdlib inline namespace names.
+    // libc++ inline namespaces.
+    //  std::__1::*       -> std::*
+    //  std::__1::__fs::* -> std::*
+    // libstdc++ inline namespaces.
+    //  std::__cxx11::*             -> std::*
+    //  std::filesystem::__cxx11::* -> std::filesystem::*
+    if (demangled_name_view.starts_with("std::")) {
+      char* begin = demangled_name_ptr.get();
+      char* to = begin + 5;  // std::
+      for (char *from = to, *end = begin + demangled_name_view.size();
+           from < end;) {
+        // This is safe, because demangled_name is NUL-terminated.
+        if (from[0] == '_' && from[1] == '_') {
+          char* next = from + 1;
+          while (next < end && *next != ':') next++;
+          if (next[0] == ':' && next[1] == ':') {
+            from = next + 2;
+            continue;
+          }
+        }
+        *to++ = *from++;
+      }
+      demangled_name_view = {begin, detail::to_unsigned(to - begin)};
+    }
+  } else {
+    demangled_name_view = string_view(ti.name());
+  }
+  return detail::write_bytes<Char>(out, demangled_name_view);
+#  elif FMT_MSC_VERSION
+  const string_view demangled_name(ti.name());
+  for (std::size_t i = 0; i < demangled_name.size(); ++i) {
+    auto sub = demangled_name;
+    sub.remove_prefix(i);
+    if (sub.starts_with("enum ")) {
+      i += 4;
+      continue;
+    }
+    if (sub.starts_with("class ") || sub.starts_with("union ")) {
+      i += 5;
+      continue;
+    }
+    if (sub.starts_with("struct ")) {
+      i += 6;
+      continue;
+    }
+    if (*sub.begin() != ' ') *out++ = *sub.begin();
+  }
+  return out;
+#  else
+  return detail::write_bytes<Char>(out, string_view(ti.name()));
+#  endif
+}
+
+}  // namespace detail
+
+FMT_EXPORT
+template <typename Char>
+struct formatter<std::type_info, Char  // DEPRECATED! Mixing code unit types.
+                 > {
+ public:
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return ctx.begin();
+  }
+
+  template <typename Context>
+  auto format(const std::type_info& ti, Context& ctx) const
+      -> decltype(ctx.out()) {
+    return detail::write_demangled_name<Char>(ctx.out(), ti);
+  }
+};
+#endif
+
+FMT_EXPORT
+template <typename T, typename Char>
+struct formatter<
+    T, Char,  // DEPRECATED! Mixing code unit types.
+    typename std::enable_if<std::is_base_of<std::exception, T>::value>::type> {
+ private:
+  bool with_typename_ = false;
+
+ public:
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    auto it = ctx.begin();
+    auto end = ctx.end();
+    if (it == end || *it == '}') return it;
+    if (*it == 't') {
+      ++it;
+      with_typename_ = FMT_USE_RTTI != 0;
+    }
+    return it;
+  }
+
+  template <typename Context>
+  auto format(const std::exception& ex, Context& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+#if FMT_USE_RTTI
+    if (with_typename_) {
+      out = detail::write_demangled_name<Char>(out, typeid(ex));
+      *out++ = ':';
+      *out++ = ' ';
+    }
+#endif
+    return detail::write_bytes<Char>(out, string_view(ex.what()));
+  }
+};
+
+namespace detail {
+
+template <typename T, typename Enable = void>
+struct has_flip : std::false_type {};
+
+template <typename T>
+struct has_flip<T, void_t<decltype(std::declval<T>().flip())>>
+    : std::true_type {};
+
+template <typename T> struct is_bit_reference_like {
+  static constexpr const bool value =
+      std::is_convertible<T, bool>::value &&
+      std::is_nothrow_assignable<T, bool>::value && has_flip<T>::value;
+};
+
+#ifdef _LIBCPP_VERSION
+
+// Workaround for libc++ incompatibility with C++ standard.
+// According to the Standard, `bitset::operator[] const` returns bool.
+template <typename C>
+struct is_bit_reference_like<std::__bit_const_reference<C>> {
+  static constexpr const bool value = true;
+};
+
+#endif
+
+}  // namespace detail
+
+// We can't use std::vector<bool, Allocator>::reference and
+// std::bitset<N>::reference because the compiler can't deduce Allocator and N
+// in partial specialization.
+FMT_EXPORT
+template <typename BitRef, typename Char>
+struct formatter<BitRef, Char,
+                 enable_if_t<detail::is_bit_reference_like<BitRef>::value>>
+    : formatter<bool, Char> {
+  template <typename FormatContext>
+  FMT_CONSTEXPR auto format(const BitRef& v, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<bool, Char>::format(v, ctx);
+  }
+};
+
+template <typename T, typename Deleter>
+auto ptr(const std::unique_ptr<T, Deleter>& p) -> const void* {
+  return p.get();
+}
+template <typename T> auto ptr(const std::shared_ptr<T>& p) -> const void* {
+  return p.get();
+}
+
+FMT_EXPORT
+template <typename T, typename Char>
+struct formatter<std::atomic<T>, Char,
+                 enable_if_t<is_formattable<T, Char>::value>>
+    : formatter<T, Char> {
+  template <typename FormatContext>
+  auto format(const std::atomic<T>& v, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<T, Char>::format(v.load(), ctx);
+  }
+};
+
+#ifdef __cpp_lib_atomic_flag_test
+FMT_EXPORT
+template <typename Char>
+struct formatter<std::atomic_flag, Char> : formatter<bool, Char> {
+  template <typename FormatContext>
+  auto format(const std::atomic_flag& v, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<bool, Char>::format(v.test(), ctx);
+  }
+};
+#endif  // __cpp_lib_atomic_flag_test
+
+FMT_EXPORT
+template <typename T, typename Char> struct formatter<std::complex<T>, Char> {
+ private:
+  detail::dynamic_format_specs<Char> specs_;
+
+  template <typename FormatContext, typename OutputIt>
+  FMT_CONSTEXPR auto do_format(const std::complex<T>& c,
+                               detail::dynamic_format_specs<Char>& specs,
+                               FormatContext& ctx, OutputIt out) const
+      -> OutputIt {
+    if (c.real() != 0) {
+      *out++ = Char('(');
+      out = detail::write<Char>(out, c.real(), specs, ctx.locale());
+      specs.set_sign(sign::plus);
+      out = detail::write<Char>(out, c.imag(), specs, ctx.locale());
+      if (!detail::isfinite(c.imag())) *out++ = Char(' ');
+      *out++ = Char('i');
+      *out++ = Char(')');
+      return out;
+    }
+    out = detail::write<Char>(out, c.imag(), specs, ctx.locale());
+    if (!detail::isfinite(c.imag())) *out++ = Char(' ');
+    *out++ = Char('i');
+    return out;
+  }
+
+ public:
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    if (ctx.begin() == ctx.end() || *ctx.begin() == '}') return ctx.begin();
+    return parse_format_specs(ctx.begin(), ctx.end(), specs_, ctx,
+                              detail::type_constant<T, Char>::value);
+  }
+
+  template <typename FormatContext>
+  auto format(const std::complex<T>& c, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto specs = specs_;
+    if (specs.dynamic()) {
+      detail::handle_dynamic_spec(specs.dynamic_width(), specs.width,
+                                  specs.width_ref, ctx);
+      detail::handle_dynamic_spec(specs.dynamic_precision(), specs.precision,
+                                  specs.precision_ref, ctx);
+    }
+
+    if (specs.width == 0) return do_format(c, specs, ctx, ctx.out());
+    auto buf = basic_memory_buffer<Char>();
+
+    auto outer_specs = format_specs();
+    outer_specs.width = specs.width;
+    outer_specs.copy_fill_from(specs);
+    outer_specs.set_align(specs.align());
+
+    specs.width = 0;
+    specs.set_fill({});
+    specs.set_align(align::none);
+
+    do_format(c, specs, ctx, basic_appender<Char>(buf));
+    return detail::write<Char>(ctx.out(),
+                               basic_string_view<Char>(buf.data(), buf.size()),
+                               outer_specs);
+  }
+};
+
+FMT_EXPORT
+template <typename T, typename Char>
+struct formatter<std::reference_wrapper<T>, Char,
+                 enable_if_t<is_formattable<remove_cvref_t<T>, Char>::value>>
+    : formatter<remove_cvref_t<T>, Char> {
+  template <typename FormatContext>
+  auto format(std::reference_wrapper<T> ref, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<remove_cvref_t<T>, Char>::format(ref.get(), ctx);
+  }
+};
+
+FMT_END_NAMESPACE
+#endif  // FMT_STD_H_

extlib/libfmt/include/fmt/xchar.h

@@ -0,0 +1,373 @@
+// Formatting library for C++ - optional wchar_t and exotic character support
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_XCHAR_H_
+#define FMT_XCHAR_H_
+
+#include "color.h"
+#include "format.h"
+#include "ostream.h"
+#include "ranges.h"
+
+#ifndef FMT_MODULE
+#  include <cwchar>
+#  if FMT_USE_LOCALE
+#    include <locale>
+#  endif
+#endif
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template <typename T>
+using is_exotic_char = bool_constant<!std::is_same<T, char>::value>;
+
+template <typename S, typename = void> struct format_string_char {};
+
+template <typename S>
+struct format_string_char<
+    S, void_t<decltype(sizeof(detail::to_string_view(std::declval<S>())))>> {
+  using type = char_t<S>;
+};
+
+template <typename S>
+struct format_string_char<
+    S, enable_if_t<std::is_base_of<detail::compile_string, S>::value>> {
+  using type = typename S::char_type;
+};
+
+template <typename S>
+using format_string_char_t = typename format_string_char<S>::type;
+
+inline auto write_loc(basic_appender<wchar_t> out, loc_value value,
+                      const format_specs& specs, locale_ref loc) -> bool {
+#if FMT_USE_LOCALE
+  auto& numpunct =
+      std::use_facet<std::numpunct<wchar_t>>(loc.get<std::locale>());
+  auto separator = std::wstring();
+  auto grouping = numpunct.grouping();
+  if (!grouping.empty()) separator = std::wstring(1, numpunct.thousands_sep());
+  return value.visit(loc_writer<wchar_t>{out, specs, separator, grouping, {}});
+#endif
+  return false;
+}
+}  // namespace detail
+
+FMT_BEGIN_EXPORT
+
+using wstring_view = basic_string_view<wchar_t>;
+using wformat_parse_context = parse_context<wchar_t>;
+using wformat_context = buffered_context<wchar_t>;
+using wformat_args = basic_format_args<wformat_context>;
+using wmemory_buffer = basic_memory_buffer<wchar_t>;
+
+template <typename Char, typename... T> struct basic_fstring {
+ private:
+  basic_string_view<Char> str_;
+
+  static constexpr int num_static_named_args =
+      detail::count_static_named_args<T...>();
+
+  using checker = detail::format_string_checker<
+      Char, static_cast<int>(sizeof...(T)), num_static_named_args,
+      num_static_named_args != detail::count_named_args<T...>()>;
+
+  using arg_pack = detail::arg_pack<T...>;
+
+ public:
+  using t = basic_fstring;
+
+  template <typename S,
+            FMT_ENABLE_IF(
+                std::is_convertible<const S&, basic_string_view<Char>>::value)>
+  FMT_CONSTEVAL FMT_ALWAYS_INLINE basic_fstring(const S& s) : str_(s) {
+    if (FMT_USE_CONSTEVAL)
+      detail::parse_format_string<Char>(s, checker(s, arg_pack()));
+  }
+  template <typename S,
+            FMT_ENABLE_IF(std::is_base_of<detail::compile_string, S>::value&&
+                              std::is_same<typename S::char_type, Char>::value)>
+  FMT_ALWAYS_INLINE basic_fstring(const S&) : str_(S()) {
+    FMT_CONSTEXPR auto sv = basic_string_view<Char>(S());
+    FMT_CONSTEXPR int ignore =
+        (parse_format_string(sv, checker(sv, arg_pack())), 0);
+    detail::ignore_unused(ignore);
+  }
+  basic_fstring(runtime_format_string<Char> fmt) : str_(fmt.str) {}
+
+  operator basic_string_view<Char>() const { return str_; }
+  auto get() const -> basic_string_view<Char> { return str_; }
+};
+
+template <typename Char, typename... T>
+using basic_format_string = basic_fstring<Char, T...>;
+
+template <typename... T>
+using wformat_string = typename basic_format_string<wchar_t, T...>::t;
+inline auto runtime(wstring_view s) -> runtime_format_string<wchar_t> {
+  return {{s}};
+}
+
+template <> struct is_char<wchar_t> : std::true_type {};
+template <> struct is_char<char16_t> : std::true_type {};
+template <> struct is_char<char32_t> : std::true_type {};
+
+#ifdef __cpp_char8_t
+template <> struct is_char<char8_t> : bool_constant<detail::is_utf8_enabled> {};
+#endif
+
+template <typename... T>
+constexpr auto make_wformat_args(T&... args)
+    -> decltype(fmt::make_format_args<wformat_context>(args...)) {
+  return fmt::make_format_args<wformat_context>(args...);
+}
+
+#if !FMT_USE_NONTYPE_TEMPLATE_ARGS
+inline namespace literals {
+inline auto operator""_a(const wchar_t* s, size_t) -> detail::udl_arg<wchar_t> {
+  return {s};
+}
+}  // namespace literals
+#endif
+
+template <typename It, typename Sentinel>
+auto join(It begin, Sentinel end, wstring_view sep)
+    -> join_view<It, Sentinel, wchar_t> {
+  return {begin, end, sep};
+}
+
+template <typename Range, FMT_ENABLE_IF(!is_tuple_like<Range>::value)>
+auto join(Range&& range, wstring_view sep)
+    -> join_view<decltype(std::begin(range)), decltype(std::end(range)),
+                 wchar_t> {
+  return join(std::begin(range), std::end(range), sep);
+}
+
+template <typename T>
+auto join(std::initializer_list<T> list, wstring_view sep)
+    -> join_view<const T*, const T*, wchar_t> {
+  return join(std::begin(list), std::end(list), sep);
+}
+
+template <typename Tuple, FMT_ENABLE_IF(is_tuple_like<Tuple>::value)>
+auto join(const Tuple& tuple, basic_string_view<wchar_t> sep)
+    -> tuple_join_view<wchar_t, Tuple> {
+  return {tuple, sep};
+}
+
+template <typename Char, FMT_ENABLE_IF(!std::is_same<Char, char>::value)>
+auto vformat(basic_string_view<Char> fmt,
+             typename detail::vformat_args<Char>::type args)
+    -> std::basic_string<Char> {
+  auto buf = basic_memory_buffer<Char>();
+  detail::vformat_to(buf, fmt, args);
+  return {buf.data(), buf.size()};
+}
+
+template <typename... T>
+auto format(wformat_string<T...> fmt, T&&... args) -> std::wstring {
+  return vformat(fmt::wstring_view(fmt), fmt::make_wformat_args(args...));
+}
+
+template <typename OutputIt, typename... T>
+auto format_to(OutputIt out, wformat_string<T...> fmt, T&&... args)
+    -> OutputIt {
+  return vformat_to(out, fmt::wstring_view(fmt),
+                    fmt::make_wformat_args(args...));
+}
+
+// Pass char_t as a default template parameter instead of using
+// std::basic_string<char_t<S>> to reduce the symbol size.
+template <typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(!std::is_same<Char, char>::value &&
+                        !std::is_same<Char, wchar_t>::value)>
+auto format(const S& fmt, T&&... args) -> std::basic_string<Char> {
+  return vformat(detail::to_string_view(fmt),
+                 fmt::make_format_args<buffered_context<Char>>(args...));
+}
+
+template <typename Locale, typename S,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_locale<Locale>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto vformat(const Locale& loc, const S& fmt,
+                    typename detail::vformat_args<Char>::type args)
+    -> std::basic_string<Char> {
+  auto buf = basic_memory_buffer<Char>();
+  detail::vformat_to(buf, detail::to_string_view(fmt), args,
+                     detail::locale_ref(loc));
+  return {buf.data(), buf.size()};
+}
+
+template <typename Locale, typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_locale<Locale>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto format(const Locale& loc, const S& fmt, T&&... args)
+    -> std::basic_string<Char> {
+  return vformat(loc, detail::to_string_view(fmt),
+                 fmt::make_format_args<buffered_context<Char>>(args...));
+}
+
+template <typename OutputIt, typename S,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_exotic_char<Char>::value)>
+auto vformat_to(OutputIt out, const S& fmt,
+                typename detail::vformat_args<Char>::type args) -> OutputIt {
+  auto&& buf = detail::get_buffer<Char>(out);
+  detail::vformat_to(buf, detail::to_string_view(fmt), args);
+  return detail::get_iterator(buf, out);
+}
+
+template <typename OutputIt, typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value &&
+                        !std::is_same<Char, char>::value &&
+                        !std::is_same<Char, wchar_t>::value)>
+inline auto format_to(OutputIt out, const S& fmt, T&&... args) -> OutputIt {
+  return vformat_to(out, detail::to_string_view(fmt),
+                    fmt::make_format_args<buffered_context<Char>>(args...));
+}
+
+template <typename Locale, typename S, typename OutputIt, typename... Args,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_locale<Locale>::value&&
+                                detail::is_exotic_char<Char>::value)>
+inline auto vformat_to(OutputIt out, const Locale& loc, const S& fmt,
+                       typename detail::vformat_args<Char>::type args)
+    -> OutputIt {
+  auto&& buf = detail::get_buffer<Char>(out);
+  vformat_to(buf, detail::to_string_view(fmt), args, detail::locale_ref(loc));
+  return detail::get_iterator(buf, out);
+}
+
+template <typename Locale, typename OutputIt, typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          bool enable = detail::is_output_iterator<OutputIt, Char>::value &&
+                        detail::is_locale<Locale>::value &&
+                        detail::is_exotic_char<Char>::value>
+inline auto format_to(OutputIt out, const Locale& loc, const S& fmt,
+                      T&&... args) ->
+    typename std::enable_if<enable, OutputIt>::type {
+  return vformat_to(out, loc, detail::to_string_view(fmt),
+                    fmt::make_format_args<buffered_context<Char>>(args...));
+}
+
+template <typename OutputIt, typename Char, typename... Args,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto vformat_to_n(OutputIt out, size_t n, basic_string_view<Char> fmt,
+                         typename detail::vformat_args<Char>::type args)
+    -> format_to_n_result<OutputIt> {
+  using traits = detail::fixed_buffer_traits;
+  auto buf = detail::iterator_buffer<OutputIt, Char, traits>(out, n);
+  detail::vformat_to(buf, fmt, args);
+  return {buf.out(), buf.count()};
+}
+
+template <typename OutputIt, typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto format_to_n(OutputIt out, size_t n, const S& fmt, T&&... args)
+    -> format_to_n_result<OutputIt> {
+  return vformat_to_n(out, n, fmt::basic_string_view<Char>(fmt),
+                      fmt::make_format_args<buffered_context<Char>>(args...));
+}
+
+template <typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_exotic_char<Char>::value)>
+inline auto formatted_size(const S& fmt, T&&... args) -> size_t {
+  auto buf = detail::counting_buffer<Char>();
+  detail::vformat_to(buf, detail::to_string_view(fmt),
+                     fmt::make_format_args<buffered_context<Char>>(args...));
+  return buf.count();
+}
+
+inline void vprint(std::FILE* f, wstring_view fmt, wformat_args args) {
+  auto buf = wmemory_buffer();
+  detail::vformat_to(buf, fmt, args);
+  buf.push_back(L'\0');
+  if (std::fputws(buf.data(), f) == -1)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot write to file")));
+}
+
+inline void vprint(wstring_view fmt, wformat_args args) {
+  vprint(stdout, fmt, args);
+}
+
+template <typename... T>
+void print(std::FILE* f, wformat_string<T...> fmt, T&&... args) {
+  return vprint(f, wstring_view(fmt), fmt::make_wformat_args(args...));
+}
+
+template <typename... T> void print(wformat_string<T...> fmt, T&&... args) {
+  return vprint(wstring_view(fmt), fmt::make_wformat_args(args...));
+}
+
+template <typename... T>
+void println(std::FILE* f, wformat_string<T...> fmt, T&&... args) {
+  return print(f, L"{}\n", fmt::format(fmt, std::forward<T>(args)...));
+}
+
+template <typename... T> void println(wformat_string<T...> fmt, T&&... args) {
+  return print(L"{}\n", fmt::format(fmt, std::forward<T>(args)...));
+}
+
+inline auto vformat(const text_style& ts, wstring_view fmt, wformat_args args)
+    -> std::wstring {
+  auto buf = wmemory_buffer();
+  detail::vformat_to(buf, ts, fmt, args);
+  return {buf.data(), buf.size()};
+}
+
+template <typename... T>
+inline auto format(const text_style& ts, wformat_string<T...> fmt, T&&... args)
+    -> std::wstring {
+  return fmt::vformat(ts, fmt, fmt::make_wformat_args(args...));
+}
+
+template <typename... T>
+FMT_DEPRECATED void print(std::FILE* f, const text_style& ts,
+                          wformat_string<T...> fmt, const T&... args) {
+  vprint(f, ts, fmt, fmt::make_wformat_args(args...));
+}
+
+template <typename... T>
+FMT_DEPRECATED void print(const text_style& ts, wformat_string<T...> fmt,
+                          const T&... args) {
+  return print(stdout, ts, fmt, args...);
+}
+
+inline void vprint(std::wostream& os, wstring_view fmt, wformat_args args) {
+  auto buffer = basic_memory_buffer<wchar_t>();
+  detail::vformat_to(buffer, fmt, args);
+  detail::write_buffer(os, buffer);
+}
+
+template <typename... T>
+void print(std::wostream& os, wformat_string<T...> fmt, T&&... args) {
+  vprint(os, fmt, fmt::make_format_args<buffered_context<wchar_t>>(args...));
+}
+
+template <typename... T>
+void println(std::wostream& os, wformat_string<T...> fmt, T&&... args) {
+  print(os, L"{}\n", fmt::format(fmt, std::forward<T>(args)...));
+}
+
+/// Converts `value` to `std::wstring` using the default format for type `T`.
+template <typename T> inline auto to_wstring(const T& value) -> std::wstring {
+  return format(FMT_STRING(L"{}"), value);
+}
+FMT_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_XCHAR_H_

extlib/libfmt/src/fmt.cc

@@ -0,0 +1,151 @@
+module;
+
+#ifdef _MSVC_LANG
+#  define FMT_CPLUSPLUS _MSVC_LANG
+#else
+#  define FMT_CPLUSPLUS __cplusplus
+#endif
+
+// Put all implementation-provided headers into the global module fragment
+// to prevent attachment to this module.
+#ifndef FMT_IMPORT_STD
+#  include <algorithm>
+#  include <bitset>
+#  include <chrono>
+#  include <cmath>
+#  include <complex>
+#  include <cstddef>
+#  include <cstdint>
+#  include <cstdio>
+#  include <cstdlib>
+#  include <cstring>
+#  include <ctime>
+#  include <exception>
+#  if FMT_CPLUSPLUS > 202002L
+#    include <expected>
+#  endif
+#  include <filesystem>
+#  include <fstream>
+#  include <functional>
+#  include <iterator>
+#  include <limits>
+#  include <locale>
+#  include <memory>
+#  include <optional>
+#  include <ostream>
+#  include <source_location>
+#  include <stdexcept>
+#  include <string>
+#  include <string_view>
+#  include <system_error>
+#  include <thread>
+#  include <type_traits>
+#  include <typeinfo>
+#  include <utility>
+#  include <variant>
+#  include <vector>
+#else
+#  include <limits.h>
+#  include <stdint.h>
+#  include <stdio.h>
+#  include <time.h>
+#endif
+#include <cerrno>
+#include <climits>
+#include <version>
+
+#if __has_include(<cxxabi.h>)
+#  include <cxxabi.h>
+#endif
+#if defined(_MSC_VER) || defined(__MINGW32__)
+#  include <intrin.h>
+#endif
+#if defined __APPLE__ || defined(__FreeBSD__)
+#  include <xlocale.h>
+#endif
+#if __has_include(<winapifamily.h>)
+#  include <winapifamily.h>
+#endif
+#if (__has_include(<fcntl.h>) || defined(__APPLE__) || \
+     defined(__linux__)) &&                            \
+    (!defined(WINAPI_FAMILY) || (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP))
+#  include <fcntl.h>
+#  include <sys/stat.h>
+#  include <sys/types.h>
+#  ifndef _WIN32
+#    include <unistd.h>
+#  else
+#    include <io.h>
+#  endif
+#endif
+#ifdef _WIN32
+#  if defined(__GLIBCXX__)
+#    include <ext/stdio_filebuf.h>
+#    include <ext/stdio_sync_filebuf.h>
+#  endif
+#  define WIN32_LEAN_AND_MEAN
+#  include <windows.h>
+#endif
+
+export module fmt;
+
+#ifdef FMT_IMPORT_STD
+import std;
+#endif
+
+#define FMT_EXPORT export
+#define FMT_BEGIN_EXPORT export {
+#define FMT_END_EXPORT }
+
+// If you define FMT_ATTACH_TO_GLOBAL_MODULE
+//  - all declarations are detached from module 'fmt'
+//  - the module behaves like a traditional static library, too
+//  - all library symbols are mangled traditionally
+//  - you can mix TUs with either importing or #including the {fmt} API
+#ifdef FMT_ATTACH_TO_GLOBAL_MODULE
+extern "C++" {
+#endif
+
+#ifndef FMT_OS
+#  define FMT_OS 1
+#endif
+
+// All library-provided declarations and definitions must be in the module
+// purview to be exported.
+#include "fmt/args.h"
+#include "fmt/chrono.h"
+#include "fmt/color.h"
+#include "fmt/compile.h"
+#include "fmt/format.h"
+#if FMT_OS
+#  include "fmt/os.h"
+#endif
+#include "fmt/ostream.h"
+#include "fmt/printf.h"
+#include "fmt/ranges.h"
+#include "fmt/std.h"
+#include "fmt/xchar.h"
+
+#ifdef FMT_ATTACH_TO_GLOBAL_MODULE
+}
+#endif
+
+// gcc doesn't yet implement private module fragments
+#if !FMT_GCC_VERSION
+module :private;
+#endif
+
+#ifdef FMT_ATTACH_TO_GLOBAL_MODULE
+extern "C++" {
+#endif
+
+#if FMT_HAS_INCLUDE("format.cc")
+#  include "format.cc"
+#endif
+#if FMT_OS && FMT_HAS_INCLUDE("os.cc")
+#  include "os.cc"
+#endif
+
+#ifdef FMT_ATTACH_TO_GLOBAL_MODULE
+}
+#endif

extlib/libfmt/src/format.cc

@@ -0,0 +1,46 @@
+// Formatting library for C++
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include "fmt/format-inl.h"
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template FMT_API auto dragonbox::to_decimal(float x) noexcept
+    -> dragonbox::decimal_fp<float>;
+template FMT_API auto dragonbox::to_decimal(double x) noexcept
+    -> dragonbox::decimal_fp<double>;
+
+#if FMT_USE_LOCALE
+// DEPRECATED! locale_ref in the detail namespace
+template FMT_API locale_ref::locale_ref(const std::locale& loc);
+template FMT_API auto locale_ref::get<std::locale>() const -> std::locale;
+#endif
+
+// Explicit instantiations for char.
+
+template FMT_API auto thousands_sep_impl(locale_ref)
+    -> thousands_sep_result<char>;
+template FMT_API auto decimal_point_impl(locale_ref) -> char;
+
+// DEPRECATED!
+template FMT_API void buffer<char>::append(const char*, const char*);
+
+// DEPRECATED!
+template FMT_API void vformat_to(buffer<char>&, string_view,
+                                 typename vformat_args<>::type, locale_ref);
+
+// Explicit instantiations for wchar_t.
+
+template FMT_API auto thousands_sep_impl(locale_ref)
+    -> thousands_sep_result<wchar_t>;
+template FMT_API auto decimal_point_impl(locale_ref) -> wchar_t;
+
+template FMT_API void buffer<wchar_t>::append(const wchar_t*, const wchar_t*);
+
+}  // namespace detail
+FMT_END_NAMESPACE

extlib/libfmt/src/os.cc

@@ -0,0 +1,398 @@
+// Formatting library for C++ - optional OS-specific functionality
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+// Disable bogus MSVC warnings.
+#if !defined(_CRT_SECURE_NO_WARNINGS) && defined(_MSC_VER)
+#  define _CRT_SECURE_NO_WARNINGS
+#endif
+
+#include "fmt/os.h"
+
+#ifndef FMT_MODULE
+#  include <climits>
+
+#  if FMT_USE_FCNTL
+#    include <sys/stat.h>
+#    include <sys/types.h>
+
+#    ifdef _WRS_KERNEL    // VxWorks7 kernel
+#      include <ioLib.h>  // getpagesize
+#    endif
+
+#    ifndef _WIN32
+#      include <unistd.h>
+#    else
+#      ifndef WIN32_LEAN_AND_MEAN
+#        define WIN32_LEAN_AND_MEAN
+#      endif
+#      include <io.h>
+#    endif  // _WIN32
+#  endif    // FMT_USE_FCNTL
+
+#  ifdef _WIN32
+#    include <windows.h>
+#  endif
+#endif
+
+#ifdef _WIN32
+#  ifndef S_IRUSR
+#    define S_IRUSR _S_IREAD
+#  endif
+#  ifndef S_IWUSR
+#    define S_IWUSR _S_IWRITE
+#  endif
+#  ifndef S_IRGRP
+#    define S_IRGRP 0
+#  endif
+#  ifndef S_IWGRP
+#    define S_IWGRP 0
+#  endif
+#  ifndef S_IROTH
+#    define S_IROTH 0
+#  endif
+#  ifndef S_IWOTH
+#    define S_IWOTH 0
+#  endif
+#endif
+
+namespace {
+#ifdef _WIN32
+// Return type of read and write functions.
+using rwresult = int;
+
+// On Windows the count argument to read and write is unsigned, so convert
+// it from size_t preventing integer overflow.
+inline unsigned convert_rwcount(std::size_t count) {
+  return count <= UINT_MAX ? static_cast<unsigned>(count) : UINT_MAX;
+}
+#elif FMT_USE_FCNTL
+// Return type of read and write functions.
+using rwresult = ssize_t;
+
+inline std::size_t convert_rwcount(std::size_t count) { return count; }
+#endif
+}  // namespace
+
+FMT_BEGIN_NAMESPACE
+
+#ifdef _WIN32
+namespace detail {
+
+class system_message {
+  system_message(const system_message&) = delete;
+  void operator=(const system_message&) = delete;
+
+  unsigned long result_;
+  wchar_t* message_;
+
+  static bool is_whitespace(wchar_t c) noexcept {
+    return c == L' ' || c == L'\n' || c == L'\r' || c == L'\t' || c == L'\0';
+  }
+
+ public:
+  explicit system_message(unsigned long error_code)
+      : result_(0), message_(nullptr) {
+    result_ = FormatMessageW(
+        FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM |
+            FORMAT_MESSAGE_IGNORE_INSERTS,
+        nullptr, error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+        reinterpret_cast<wchar_t*>(&message_), 0, nullptr);
+    if (result_ != 0) {
+      while (result_ != 0 && is_whitespace(message_[result_ - 1])) {
+        --result_;
+      }
+    }
+  }
+  ~system_message() { LocalFree(message_); }
+  explicit operator bool() const noexcept { return result_ != 0; }
+  operator basic_string_view<wchar_t>() const noexcept {
+    return basic_string_view<wchar_t>(message_, result_);
+  }
+};
+
+class utf8_system_category final : public std::error_category {
+ public:
+  const char* name() const noexcept override { return "system"; }
+  std::string message(int error_code) const override {
+    auto&& msg = system_message(error_code);
+    if (msg) {
+      auto utf8_message = to_utf8<wchar_t>();
+      if (utf8_message.convert(msg)) {
+        return utf8_message.str();
+      }
+    }
+    return "unknown error";
+  }
+};
+
+}  // namespace detail
+
+FMT_API const std::error_category& system_category() noexcept {
+  static const detail::utf8_system_category category;
+  return category;
+}
+
+std::system_error vwindows_error(int err_code, string_view format_str,
+                                 format_args args) {
+  auto ec = std::error_code(err_code, system_category());
+  return std::system_error(ec, vformat(format_str, args));
+}
+
+void detail::format_windows_error(detail::buffer<char>& out, int error_code,
+                                  const char* message) noexcept {
+  FMT_TRY {
+    auto&& msg = system_message(error_code);
+    if (msg) {
+      auto utf8_message = to_utf8<wchar_t>();
+      if (utf8_message.convert(msg)) {
+        fmt::format_to(appender(out), FMT_STRING("{}: {}"), message,
+                       string_view(utf8_message));
+        return;
+      }
+    }
+  }
+  FMT_CATCH(...) {}
+  format_error_code(out, error_code, message);
+}
+
+void report_windows_error(int error_code, const char* message) noexcept {
+  do_report_error(detail::format_windows_error, error_code, message);
+}
+#endif  // _WIN32
+
+buffered_file::~buffered_file() noexcept {
+  if (file_ && FMT_SYSTEM(fclose(file_)) != 0)
+    report_system_error(errno, "cannot close file");
+}
+
+buffered_file::buffered_file(cstring_view filename, cstring_view mode) {
+  FMT_RETRY_VAL(file_, FMT_SYSTEM(fopen(filename.c_str(), mode.c_str())),
+                nullptr);
+  if (!file_)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot open file {}"),
+                           filename.c_str()));
+}
+
+void buffered_file::close() {
+  if (!file_) return;
+  int result = FMT_SYSTEM(fclose(file_));
+  file_ = nullptr;
+  if (result != 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot close file")));
+}
+
+int buffered_file::descriptor() const {
+#ifdef FMT_HAS_SYSTEM
+  // fileno is a macro on OpenBSD.
+#  ifdef fileno
+#    undef fileno
+#  endif
+  int fd = FMT_POSIX_CALL(fileno(file_));
+#elif defined(_WIN32)
+  int fd = _fileno(file_);
+#else
+  int fd = fileno(file_);
+#endif
+  if (fd == -1)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot get file descriptor")));
+  return fd;
+}
+
+#if FMT_USE_FCNTL
+#  ifdef _WIN32
+using mode_t = int;
+#  endif
+
+constexpr mode_t default_open_mode =
+    S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
+
+file::file(cstring_view path, int oflag) {
+#  if defined(_WIN32) && !defined(__MINGW32__)
+  fd_ = -1;
+  auto converted = detail::utf8_to_utf16(string_view(path.c_str()));
+  *this = file::open_windows_file(converted.c_str(), oflag);
+#  else
+  FMT_RETRY(fd_, FMT_POSIX_CALL(open(path.c_str(), oflag, default_open_mode)));
+  if (fd_ == -1)
+    FMT_THROW(
+        system_error(errno, FMT_STRING("cannot open file {}"), path.c_str()));
+#  endif
+}
+
+file::~file() noexcept {
+  // Don't retry close in case of EINTR!
+  // See http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-09/3000.html
+  if (fd_ != -1 && FMT_POSIX_CALL(close(fd_)) != 0)
+    report_system_error(errno, "cannot close file");
+}
+
+void file::close() {
+  if (fd_ == -1) return;
+  // Don't retry close in case of EINTR!
+  // See http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-09/3000.html
+  int result = FMT_POSIX_CALL(close(fd_));
+  fd_ = -1;
+  if (result != 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot close file")));
+}
+
+long long file::size() const {
+#  ifdef _WIN32
+  // Use GetFileSize instead of GetFileSizeEx for the case when _WIN32_WINNT
+  // is less than 0x0500 as is the case with some default MinGW builds.
+  // Both functions support large file sizes.
+  DWORD size_upper = 0;
+  HANDLE handle = reinterpret_cast<HANDLE>(_get_osfhandle(fd_));
+  DWORD size_lower = FMT_SYSTEM(GetFileSize(handle, &size_upper));
+  if (size_lower == INVALID_FILE_SIZE) {
+    DWORD error = GetLastError();
+    if (error != NO_ERROR)
+      FMT_THROW(windows_error(GetLastError(), "cannot get file size"));
+  }
+  unsigned long long long_size = size_upper;
+  return (long_size << sizeof(DWORD) * CHAR_BIT) | size_lower;
+#  else
+  using Stat = struct stat;
+  Stat file_stat = Stat();
+  if (FMT_POSIX_CALL(fstat(fd_, &file_stat)) == -1)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot get file attributes")));
+  static_assert(sizeof(long long) >= sizeof(file_stat.st_size),
+                "return type of file::size is not large enough");
+  return file_stat.st_size;
+#  endif
+}
+
+std::size_t file::read(void* buffer, std::size_t count) {
+  rwresult result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(read(fd_, buffer, convert_rwcount(count))));
+  if (result < 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot read from file")));
+  return detail::to_unsigned(result);
+}
+
+std::size_t file::write(const void* buffer, std::size_t count) {
+  rwresult result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(write(fd_, buffer, convert_rwcount(count))));
+  if (result < 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot write to file")));
+  return detail::to_unsigned(result);
+}
+
+file file::dup(int fd) {
+  // Don't retry as dup doesn't return EINTR.
+  // http://pubs.opengroup.org/onlinepubs/009695399/functions/dup.html
+  int new_fd = FMT_POSIX_CALL(dup(fd));
+  if (new_fd == -1)
+    FMT_THROW(system_error(
+        errno, FMT_STRING("cannot duplicate file descriptor {}"), fd));
+  return file(new_fd);
+}
+
+void file::dup2(int fd) {
+  int result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(dup2(fd_, fd)));
+  if (result == -1) {
+    FMT_THROW(system_error(
+        errno, FMT_STRING("cannot duplicate file descriptor {} to {}"), fd_,
+        fd));
+  }
+}
+
+void file::dup2(int fd, std::error_code& ec) noexcept {
+  int result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(dup2(fd_, fd)));
+  if (result == -1) ec = std::error_code(errno, std::generic_category());
+}
+
+buffered_file file::fdopen(const char* mode) {
+// Don't retry as fdopen doesn't return EINTR.
+#  if defined(__MINGW32__) && defined(_POSIX_)
+  FILE* f = ::fdopen(fd_, mode);
+#  else
+  FILE* f = FMT_POSIX_CALL(fdopen(fd_, mode));
+#  endif
+  if (!f) {
+    FMT_THROW(system_error(
+        errno, FMT_STRING("cannot associate stream with file descriptor")));
+  }
+  buffered_file bf(f);
+  fd_ = -1;
+  return bf;
+}
+
+#  if defined(_WIN32) && !defined(__MINGW32__)
+file file::open_windows_file(wcstring_view path, int oflag) {
+  int fd = -1;
+  auto err = _wsopen_s(&fd, path.c_str(), oflag, _SH_DENYNO, default_open_mode);
+  if (fd == -1) {
+    FMT_THROW(system_error(err, FMT_STRING("cannot open file {}"),
+                           detail::to_utf8<wchar_t>(path.c_str()).c_str()));
+  }
+  return file(fd);
+}
+#  endif
+
+pipe::pipe() {
+  int fds[2] = {};
+#  ifdef _WIN32
+  // Make the default pipe capacity same as on Linux 2.6.11+.
+  enum { DEFAULT_CAPACITY = 65536 };
+  int result = FMT_POSIX_CALL(pipe(fds, DEFAULT_CAPACITY, _O_BINARY));
+#  else
+  // Don't retry as the pipe function doesn't return EINTR.
+  // http://pubs.opengroup.org/onlinepubs/009696799/functions/pipe.html
+  int result = FMT_POSIX_CALL(pipe(fds));
+#  endif
+  if (result != 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot create pipe")));
+  // The following assignments don't throw.
+  read_end = file(fds[0]);
+  write_end = file(fds[1]);
+}
+
+#  if !defined(__MSDOS__)
+long getpagesize() {
+#    ifdef _WIN32
+  SYSTEM_INFO si;
+  GetSystemInfo(&si);
+  return si.dwPageSize;
+#    else
+#      ifdef _WRS_KERNEL
+  long size = FMT_POSIX_CALL(getpagesize());
+#      else
+  long size = FMT_POSIX_CALL(sysconf(_SC_PAGESIZE));
+#      endif
+
+  if (size < 0)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot get memory page size")));
+  return size;
+#    endif
+}
+#  endif
+
+void ostream::grow(buffer<char>& buf, size_t) {
+  if (buf.size() == buf.capacity()) static_cast<ostream&>(buf).flush();
+}
+
+ostream::ostream(cstring_view path, const detail::ostream_params& params)
+    : buffer<char>(grow), file_(path, params.oflag) {
+  set(new char[params.buffer_size], params.buffer_size);
+}
+
+ostream::ostream(ostream&& other) noexcept
+    : buffer<char>(grow, other.data(), other.size(), other.capacity()),
+      file_(std::move(other.file_)) {
+  other.clear();
+  other.set(nullptr, 0);
+}
+
+ostream::~ostream() {
+  flush();
+  delete[] data();
+}
+#endif  // FMT_USE_FCNTL
+FMT_END_NAMESPACE

extlib/libfmt/support/Android.mk

@@ -0,0 +1,15 @@
+LOCAL_PATH := $(call my-dir)
+include $(CLEAR_VARS)
+
+LOCAL_MODULE := fmt_static
+LOCAL_MODULE_FILENAME := libfmt
+
+LOCAL_SRC_FILES := ../src/format.cc
+
+LOCAL_C_INCLUDES := $(LOCAL_PATH)
+LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)
+
+LOCAL_CFLAGS += -std=c++11 -fexceptions
+
+include $(BUILD_STATIC_LIBRARY)
+

extlib/libfmt/support/AndroidManifest.xml

@@ -0,0 +1 @@
+<manifest package="dev.fmt" />

extlib/libfmt/support/README

@@ -0,0 +1,4 @@
+This directory contains build support files such as
+
+* CMake modules
+* Build scripts

extlib/libfmt/support/Vagrantfile

@@ -0,0 +1,19 @@
+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+# A vagrant config for testing against gcc-4.8.
+Vagrant.configure("2") do |config|
+  config.vm.box = "bento/ubuntu-22.04-arm64"
+
+  config.vm.provider "vmware_desktop" do |vb|
+    vb.memory = "4096"
+  end
+
+  config.vm.provision "shell", inline: <<-SHELL
+    apt-get update
+    apt-get install -y g++ make wget git
+    wget -q https://github.com/Kitware/CMake/releases/download/v3.26.0/cmake-3.26.0-Linux-x86_64.tar.gz
+    tar xzf cmake-3.26.0-Linux-x86_64.tar.gz
+    ln -s `pwd`/cmake-3.26.0-Linux-x86_64/bin/cmake /usr/local/bin
+  SHELL
+end

extlib/libfmt/support/bazel/.bazelversion

@@ -0,0 +1 @@
+7.1.2

extlib/libfmt/support/bazel/BUILD.bazel

@@ -0,0 +1,20 @@
+cc_library(
+    name = "fmt",
+    srcs = [
+        #"src/fmt.cc", # No C++ module support, yet in Bazel (https://github.com/bazelbuild/bazel/pull/19940)
+        "src/format.cc",
+        "src/os.cc",
+    ],
+    hdrs = glob([
+        "include/fmt/*.h",
+    ]),
+    copts = select({
+        "@platforms//os:windows": ["-utf-8"],
+        "//conditions:default": [],
+    }),
+    includes = [
+        "include",
+    ],
+    strip_include_prefix = "include",
+    visibility = ["//visibility:public"],
+)

extlib/libfmt/support/bazel/MODULE.bazel

@@ -0,0 +1,6 @@
+module(
+   name = "fmt",
+   compatibility_level = 10,
+)
+
+bazel_dep(name = "platforms", version = "0.0.10")

extlib/libfmt/support/bazel/README.md

@@ -0,0 +1,28 @@
+# Bazel support
+
+To get [Bazel](https://bazel.build/) working with {fmt} you can copy the files `BUILD.bazel`, 
+`MODULE.bazel`, `WORKSPACE.bazel`, and `.bazelversion` from this folder (`support/bazel`) to the root folder of this project. 
+This way {fmt} gets bazelized and can be used with Bazel (e.g. doing a `bazel build //...` on {fmt}). 
+
+## Using {fmt} as a dependency
+
+### Using Bzlmod
+
+The [Bazel Central Registry](https://github.com/bazelbuild/bazel-central-registry/tree/main/modules/fmt) provides support for {fmt}.
+
+For instance, to use {fmt} add to your `MODULE.bazel` file:
+
+```
+bazel_dep(name = "fmt", version = "10.2.1")
+```
+
+### Live at head
+
+For a live-at-head approach, you can copy the contents of this repository and move the Bazel-related build files to the root folder of this project as described above and make use of `local_path_override`, e.g.:
+
+```
+local_path_override(
+    module_name = "fmt",
+    path = "../third_party/fmt",
+)
+```

extlib/libfmt/support/bazel/WORKSPACE.bazel

@@ -0,0 +1,2 @@
+# WORKSPACE marker file needed by Bazel
+

extlib/libfmt/support/build.gradle

@@ -0,0 +1,132 @@
+import java.nio.file.Paths
+
+// General gradle arguments for root project
+buildscript {    
+    repositories {
+        google()
+        jcenter()
+    }
+    dependencies {
+        //
+        // https://developer.android.com/studio/releases/gradle-plugin#updating-gradle
+        //
+        // Notice that 4.0.0 here is the version of [Android Gradle Plugin]
+        // According to URL above you will need Gradle 6.1 or higher
+        //
+        classpath "com.android.tools.build:gradle:4.1.1"
+    }
+}
+repositories {
+    google()
+    jcenter()
+}
+
+// Project's root where CMakeLists.txt exists: rootDir/support/.cxx -> rootDir
+def rootDir = Paths.get(project.buildDir.getParent()).getParent()
+println("rootDir: ${rootDir}")
+
+// Output: Shared library (.so) for Android 
+apply plugin: "com.android.library"
+android {
+    compileSdkVersion 25    // Android 7.0
+
+    // Target ABI
+    //  - This option controls target platform of module
+    //  - The platform might be limited by compiler's support
+    //    some can work with Clang(default), but some can work only with GCC...
+    //    if bad, both toolchains might not support it
+    splits {
+        abi {
+            enable true
+            // Specify platforms for Application
+            reset()
+            include  "arm64-v8a", "armeabi-v7a", "x86_64"
+        }
+    }
+    ndkVersion "21.3.6528147" // ANDROID_NDK_HOME is deprecated. Be explicit
+
+    defaultConfig {
+        minSdkVersion 21    // Android 5.0+
+        targetSdkVersion 25 // Follow Compile SDK
+        versionCode 34      // Follow release count
+        versionName "7.1.2" // Follow Official version
+        
+        externalNativeBuild {
+            cmake {
+                arguments "-DANDROID_STL=c++_shared"    // Specify Android STL
+                arguments "-DBUILD_SHARED_LIBS=true"    // Build shared object
+                arguments "-DFMT_TEST=false"            // Skip test
+                arguments "-DFMT_DOC=false"             // Skip document
+                cppFlags  "-std=c++17"
+                targets   "fmt"
+            }
+        }
+        println(externalNativeBuild.cmake.cppFlags)
+        println(externalNativeBuild.cmake.arguments)
+    }
+
+    // External Native build
+    //  - Use existing CMakeList.txt
+    //  - Give path to CMake. This gradle file should be 
+    //    neighbor of the top level cmake
+    externalNativeBuild {
+        cmake {
+            version "3.10.0+"
+            path "${rootDir}/CMakeLists.txt"
+            // buildStagingDirectory "./build"  // Custom path for cmake output
+        }
+    }
+    
+    sourceSets{
+        // Android Manifest for Gradle
+        main {
+            manifest.srcFile "AndroidManifest.xml"
+        }
+    }
+
+    // https://developer.android.com/studio/build/native-dependencies#build_system_configuration
+    buildFeatures {
+        prefab true
+        prefabPublishing true
+    }
+    prefab {
+        fmt {
+            headers "${rootDir}/include"
+        }
+    }
+}
+
+assemble.doLast
+{
+    // Instead of `ninja install`, Gradle will deploy the files.
+    // We are doing this since FMT is dependent to the ANDROID_STL after build
+    copy {
+        from "build/intermediates/cmake"
+        into "${rootDir}/libs"
+    }
+    // Copy debug binaries
+    copy {
+        from "${rootDir}/libs/debug/obj"
+        into "${rootDir}/libs/debug"
+    }
+    // Copy Release binaries
+    copy {
+        from "${rootDir}/libs/release/obj"
+        into "${rootDir}/libs/release"
+    }
+    // Remove empty directory
+    delete "${rootDir}/libs/debug/obj"
+    delete "${rootDir}/libs/release/obj"
+
+    // Copy AAR files. Notice that the aar is named after the folder of this script.
+    copy {
+        from "build/outputs/aar/support-release.aar"
+        into "${rootDir}/libs"
+        rename "support-release.aar", "fmt-release.aar"
+    }
+    copy {
+        from "build/outputs/aar/support-debug.aar"
+        into "${rootDir}/libs"
+        rename "support-debug.aar", "fmt-debug.aar"
+    }
+}

extlib/libfmt/support/check-commits

@@ -0,0 +1,43 @@
+#!/usr/bin/env python3
+
+"""Compile source on a range of commits
+
+Usage:
+  check-commits <start> <source>
+"""
+
+import docopt, os, sys, tempfile
+from subprocess import check_call, check_output, run
+
+args = docopt.docopt(__doc__)
+start = args.get('<start>')
+source = args.get('<source>')
+
+cwd = os.getcwd()
+
+with tempfile.TemporaryDirectory() as work_dir:
+  check_call(['git', 'clone', 'https://github.com/fmtlib/fmt.git'],
+             cwd=work_dir)
+  repo_dir = os.path.join(work_dir, 'fmt')
+  commits = check_output(
+    ['git', 'rev-list', f'{start}..HEAD', '--abbrev-commit',
+     '--', 'include', 'src'],
+    text=True, cwd=repo_dir).rstrip().split('\n')
+  commits.reverse()
+  print('Time\tCommit')
+  for commit in commits:
+    check_call(['git', '-c', 'advice.detachedHead=false', 'checkout', commit],
+               cwd=repo_dir)
+    returncode = run(
+      ['c++', '-std=c++11', '-O3', '-DNDEBUG', '-I', 'include',
+       'src/format.cc', os.path.join(cwd, source)], cwd=repo_dir).returncode
+    if returncode != 0:
+      continue
+    times = []
+    for i in range(5):
+      output = check_output([os.path.join(repo_dir, 'a.out')], text=True)
+      times.append(float(output))
+    message = check_output(['git', 'log', '-1', '--pretty=format:%s', commit],
+                           cwd=repo_dir, text=True)
+    print(f'{min(times)}\t{commit} {message[:40]}')
+    sys.stdout.flush()

extlib/libfmt/support/cmake/FindSetEnv.cmake

@@ -0,0 +1,7 @@
+# A CMake script to find SetEnv.cmd.
+
+find_program(WINSDK_SETENV NAMES SetEnv.cmd
+  PATHS "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Microsoft SDKs\\Windows;CurrentInstallFolder]/bin")
+if (WINSDK_SETENV AND PRINT_PATH)
+  execute_process(COMMAND ${CMAKE_COMMAND} -E echo "${WINSDK_SETENV}")
+endif ()

extlib/libfmt/support/cmake/JoinPaths.cmake

@@ -0,0 +1,26 @@
+# This module provides function for joining paths
+# known from from most languages
+#
+# Original license:
+# SPDX-License-Identifier: (MIT OR CC0-1.0)
+# Explicit permission given to distribute this module under
+# the terms of the project as described in /LICENSE.rst.
+# Copyright 2020 Jan Tojnar
+# https://github.com/jtojnar/cmake-snips
+#
+# Modelled after Python’s os.path.join
+# https://docs.python.org/3.7/library/os.path.html#os.path.join
+# Windows not supported
+function(join_paths joined_path first_path_segment)
+    set(temp_path "${first_path_segment}")
+    foreach(current_segment IN LISTS ARGN)
+        if(NOT ("${current_segment}" STREQUAL ""))
+            if(IS_ABSOLUTE "${current_segment}")
+                set(temp_path "${current_segment}")
+            else()
+                set(temp_path "${temp_path}/${current_segment}")
+            endif()
+        endif()
+    endforeach()
+    set(${joined_path} "${temp_path}" PARENT_SCOPE)
+endfunction()

extlib/libfmt/support/cmake/fmt-config.cmake.in

@@ -0,0 +1,7 @@
+@PACKAGE_INIT@
+
+if (NOT TARGET fmt::fmt)
+  include(${CMAKE_CURRENT_LIST_DIR}/@targets_export_name@.cmake)
+endif ()
+
+check_required_components(fmt)

extlib/libfmt/support/cmake/fmt.pc.in

@@ -0,0 +1,11 @@
+prefix=@CMAKE_INSTALL_PREFIX@
+exec_prefix=@CMAKE_INSTALL_PREFIX@
+libdir=@libdir_for_pc_file@
+includedir=@includedir_for_pc_file@
+
+Name: fmt
+Description: A modern formatting library
+Version: @FMT_VERSION@
+Libs: -L${libdir} -l@FMT_LIB_NAME@
+Cflags: -I${includedir}
+

extlib/libfmt/support/docopt.py

@@ -0,0 +1,581 @@
+"""Pythonic command-line interface parser that will make you smile.
+
+ * http://docopt.org
+ * Repository and issue-tracker: https://github.com/docopt/docopt
+ * Licensed under terms of MIT license (see LICENSE-MIT)
+ * Copyright (c) 2013 Vladimir Keleshev, vladimir@keleshev.com
+
+"""
+import sys
+import re
+
+
+__all__ = ['docopt']
+__version__ = '0.6.1'
+
+
+class DocoptLanguageError(Exception):
+
+    """Error in construction of usage-message by developer."""
+
+
+class DocoptExit(SystemExit):
+
+    """Exit in case user invoked program with incorrect arguments."""
+
+    usage = ''
+
+    def __init__(self, message=''):
+        SystemExit.__init__(self, (message + '\n' + self.usage).strip())
+
+
+class Pattern(object):
+
+    def __eq__(self, other):
+        return repr(self) == repr(other)
+
+    def __hash__(self):
+        return hash(repr(self))
+
+    def fix(self):
+        self.fix_identities()
+        self.fix_repeating_arguments()
+        return self
+
+    def fix_identities(self, uniq=None):
+        """Make pattern-tree tips point to same object if they are equal."""
+        if not hasattr(self, 'children'):
+            return self
+        uniq = list(set(self.flat())) if uniq is None else uniq
+        for i, child in enumerate(self.children):
+            if not hasattr(child, 'children'):
+                assert child in uniq
+                self.children[i] = uniq[uniq.index(child)]
+            else:
+                child.fix_identities(uniq)
+
+    def fix_repeating_arguments(self):
+        """Fix elements that should accumulate/increment values."""
+        either = [list(child.children) for child in transform(self).children]
+        for case in either:
+            for e in [child for child in case if case.count(child) > 1]:
+                if type(e) is Argument or type(e) is Option and e.argcount:
+                    if e.value is None:
+                        e.value = []
+                    elif type(e.value) is not list:
+                        e.value = e.value.split()
+                if type(e) is Command or type(e) is Option and e.argcount == 0:
+                    e.value = 0
+        return self
+
+
+def transform(pattern):
+    """Expand pattern into an (almost) equivalent one, but with single Either.
+
+    Example: ((-a | -b) (-c | -d)) => (-a -c | -a -d | -b -c | -b -d)
+    Quirks: [-a] => (-a), (-a...) => (-a -a)
+
+    """
+    result = []
+    groups = [[pattern]]
+    while groups:
+        children = groups.pop(0)
+        parents = [Required, Optional, OptionsShortcut, Either, OneOrMore]
+        if any(t in map(type, children) for t in parents):
+            child = [c for c in children if type(c) in parents][0]
+            children.remove(child)
+            if type(child) is Either:
+                for c in child.children:
+                    groups.append([c] + children)
+            elif type(child) is OneOrMore:
+                groups.append(child.children * 2 + children)
+            else:
+                groups.append(child.children + children)
+        else:
+            result.append(children)
+    return Either(*[Required(*e) for e in result])
+
+
+class LeafPattern(Pattern):
+
+    """Leaf/terminal node of a pattern tree."""
+
+    def __init__(self, name, value=None):
+        self.name, self.value = name, value
+
+    def __repr__(self):
+        return '%s(%r, %r)' % (self.__class__.__name__, self.name, self.value)
+
+    def flat(self, *types):
+        return [self] if not types or type(self) in types else []
+
+    def match(self, left, collected=None):
+        collected = [] if collected is None else collected
+        pos, match = self.single_match(left)
+        if match is None:
+            return False, left, collected
+        left_ = left[:pos] + left[pos + 1:]
+        same_name = [a for a in collected if a.name == self.name]
+        if type(self.value) in (int, list):
+            if type(self.value) is int:
+                increment = 1
+            else:
+                increment = ([match.value] if type(match.value) is str
+                             else match.value)
+            if not same_name:
+                match.value = increment
+                return True, left_, collected + [match]
+            same_name[0].value += increment
+            return True, left_, collected
+        return True, left_, collected + [match]
+
+
+class BranchPattern(Pattern):
+
+    """Branch/inner node of a pattern tree."""
+
+    def __init__(self, *children):
+        self.children = list(children)
+
+    def __repr__(self):
+        return '%s(%s)' % (self.__class__.__name__,
+                           ', '.join(repr(a) for a in self.children))
+
+    def flat(self, *types):
+        if type(self) in types:
+            return [self]
+        return sum([child.flat(*types) for child in self.children], [])
+
+
+class Argument(LeafPattern):
+
+    def single_match(self, left):
+        for n, pattern in enumerate(left):
+            if type(pattern) is Argument:
+                return n, Argument(self.name, pattern.value)
+        return None, None
+
+    @classmethod
+    def parse(class_, source):
+        name = re.findall('(<\S*?>)', source)[0]
+        value = re.findall('\[default: (.*)\]', source, flags=re.I)
+        return class_(name, value[0] if value else None)
+
+
+class Command(Argument):
+
+    def __init__(self, name, value=False):
+        self.name, self.value = name, value
+
+    def single_match(self, left):
+        for n, pattern in enumerate(left):
+            if type(pattern) is Argument:
+                if pattern.value == self.name:
+                    return n, Command(self.name, True)
+                else:
+                    break
+        return None, None
+
+
+class Option(LeafPattern):
+
+    def __init__(self, short=None, long=None, argcount=0, value=False):
+        assert argcount in (0, 1)
+        self.short, self.long, self.argcount = short, long, argcount
+        self.value = None if value is False and argcount else value
+
+    @classmethod
+    def parse(class_, option_description):
+        short, long, argcount, value = None, None, 0, False
+        options, _, description = option_description.strip().partition('  ')
+        options = options.replace(',', ' ').replace('=', ' ')
+        for s in options.split():
+            if s.startswith('--'):
+                long = s
+            elif s.startswith('-'):
+                short = s
+            else:
+                argcount = 1
+        if argcount:
+            matched = re.findall('\[default: (.*)\]', description, flags=re.I)
+            value = matched[0] if matched else None
+        return class_(short, long, argcount, value)
+
+    def single_match(self, left):
+        for n, pattern in enumerate(left):
+            if self.name == pattern.name:
+                return n, pattern
+        return None, None
+
+    @property
+    def name(self):
+        return self.long or self.short
+
+    def __repr__(self):
+        return 'Option(%r, %r, %r, %r)' % (self.short, self.long,
+                                           self.argcount, self.value)
+
+
+class Required(BranchPattern):
+
+    def match(self, left, collected=None):
+        collected = [] if collected is None else collected
+        l = left
+        c = collected
+        for pattern in self.children:
+            matched, l, c = pattern.match(l, c)
+            if not matched:
+                return False, left, collected
+        return True, l, c
+
+
+class Optional(BranchPattern):
+
+    def match(self, left, collected=None):
+        collected = [] if collected is None else collected
+        for pattern in self.children:
+            m, left, collected = pattern.match(left, collected)
+        return True, left, collected
+
+
+class OptionsShortcut(Optional):
+
+    """Marker/placeholder for [options] shortcut."""
+
+
+class OneOrMore(BranchPattern):
+
+    def match(self, left, collected=None):
+        assert len(self.children) == 1
+        collected = [] if collected is None else collected
+        l = left
+        c = collected
+        l_ = None
+        matched = True
+        times = 0
+        while matched:
+            # could it be that something didn't match but changed l or c?
+            matched, l, c = self.children[0].match(l, c)
+            times += 1 if matched else 0
+            if l_ == l:
+                break
+            l_ = l
+        if times >= 1:
+            return True, l, c
+        return False, left, collected
+
+
+class Either(BranchPattern):
+
+    def match(self, left, collected=None):
+        collected = [] if collected is None else collected
+        outcomes = []
+        for pattern in self.children:
+            matched, _, _ = outcome = pattern.match(left, collected)
+            if matched:
+                outcomes.append(outcome)
+        if outcomes:
+            return min(outcomes, key=lambda outcome: len(outcome[1]))
+        return False, left, collected
+
+
+class Tokens(list):
+
+    def __init__(self, source, error=DocoptExit):
+        self += source.split() if hasattr(source, 'split') else source
+        self.error = error
+
+    @staticmethod
+    def from_pattern(source):
+        source = re.sub(r'([\[\]\(\)\|]|\.\.\.)', r' \1 ', source)
+        source = [s for s in re.split('\s+|(\S*<.*?>)', source) if s]
+        return Tokens(source, error=DocoptLanguageError)
+
+    def move(self):
+        return self.pop(0) if len(self) else None
+
+    def current(self):
+        return self[0] if len(self) else None
+
+
+def parse_long(tokens, options):
+    """long ::= '--' chars [ ( ' ' | '=' ) chars ] ;"""
+    long, eq, value = tokens.move().partition('=')
+    assert long.startswith('--')
+    value = None if eq == value == '' else value
+    similar = [o for o in options if o.long == long]
+    if tokens.error is DocoptExit and similar == []:  # if no exact match
+        similar = [o for o in options if o.long and o.long.startswith(long)]
+    if len(similar) > 1:  # might be simply specified ambiguously 2+ times?
+        raise tokens.error('%s is not a unique prefix: %s?' %
+                           (long, ', '.join(o.long for o in similar)))
+    elif len(similar) < 1:
+        argcount = 1 if eq == '=' else 0
+        o = Option(None, long, argcount)
+        options.append(o)
+        if tokens.error is DocoptExit:
+            o = Option(None, long, argcount, value if argcount else True)
+    else:
+        o = Option(similar[0].short, similar[0].long,
+                   similar[0].argcount, similar[0].value)
+        if o.argcount == 0:
+            if value is not None:
+                raise tokens.error('%s must not have an argument' % o.long)
+        else:
+            if value is None:
+                if tokens.current() in [None, '--']:
+                    raise tokens.error('%s requires argument' % o.long)
+                value = tokens.move()
+        if tokens.error is DocoptExit:
+            o.value = value if value is not None else True
+    return [o]
+
+
+def parse_shorts(tokens, options):
+    """shorts ::= '-' ( chars )* [ [ ' ' ] chars ] ;"""
+    token = tokens.move()
+    assert token.startswith('-') and not token.startswith('--')
+    left = token.lstrip('-')
+    parsed = []
+    while left != '':
+        short, left = '-' + left[0], left[1:]
+        similar = [o for o in options if o.short == short]
+        if len(similar) > 1:
+            raise tokens.error('%s is specified ambiguously %d times' %
+                               (short, len(similar)))
+        elif len(similar) < 1:
+            o = Option(short, None, 0)
+            options.append(o)
+            if tokens.error is DocoptExit:
+                o = Option(short, None, 0, True)
+        else:  # why copying is necessary here?
+            o = Option(short, similar[0].long,
+                       similar[0].argcount, similar[0].value)
+            value = None
+            if o.argcount != 0:
+                if left == '':
+                    if tokens.current() in [None, '--']:
+                        raise tokens.error('%s requires argument' % short)
+                    value = tokens.move()
+                else:
+                    value = left
+                    left = ''
+            if tokens.error is DocoptExit:
+                o.value = value if value is not None else True
+        parsed.append(o)
+    return parsed
+
+
+def parse_pattern(source, options):
+    tokens = Tokens.from_pattern(source)
+    result = parse_expr(tokens, options)
+    if tokens.current() is not None:
+        raise tokens.error('unexpected ending: %r' % ' '.join(tokens))
+    return Required(*result)
+
+
+def parse_expr(tokens, options):
+    """expr ::= seq ( '|' seq )* ;"""
+    seq = parse_seq(tokens, options)
+    if tokens.current() != '|':
+        return seq
+    result = [Required(*seq)] if len(seq) > 1 else seq
+    while tokens.current() == '|':
+        tokens.move()
+        seq = parse_seq(tokens, options)
+        result += [Required(*seq)] if len(seq) > 1 else seq
+    return [Either(*result)] if len(result) > 1 else result
+
+
+def parse_seq(tokens, options):
+    """seq ::= ( atom [ '...' ] )* ;"""
+    result = []
+    while tokens.current() not in [None, ']', ')', '|']:
+        atom = parse_atom(tokens, options)
+        if tokens.current() == '...':
+            atom = [OneOrMore(*atom)]
+            tokens.move()
+        result += atom
+    return result
+
+
+def parse_atom(tokens, options):
+    """atom ::= '(' expr ')' | '[' expr ']' | 'options'
+             | long | shorts | argument | command ;
+    """
+    token = tokens.current()
+    result = []
+    if token in '([':
+        tokens.move()
+        matching, pattern = {'(': [')', Required], '[': [']', Optional]}[token]
+        result = pattern(*parse_expr(tokens, options))
+        if tokens.move() != matching:
+            raise tokens.error("unmatched '%s'" % token)
+        return [result]
+    elif token == 'options':
+        tokens.move()
+        return [OptionsShortcut()]
+    elif token.startswith('--') and token != '--':
+        return parse_long(tokens, options)
+    elif token.startswith('-') and token not in ('-', '--'):
+        return parse_shorts(tokens, options)
+    elif token.startswith('<') and token.endswith('>') or token.isupper():
+        return [Argument(tokens.move())]
+    else:
+        return [Command(tokens.move())]
+
+
+def parse_argv(tokens, options, options_first=False):
+    """Parse command-line argument vector.
+
+    If options_first:
+        argv ::= [ long | shorts ]* [ argument ]* [ '--' [ argument ]* ] ;
+    else:
+        argv ::= [ long | shorts | argument ]* [ '--' [ argument ]* ] ;
+
+    """
+    parsed = []
+    while tokens.current() is not None:
+        if tokens.current() == '--':
+            return parsed + [Argument(None, v) for v in tokens]
+        elif tokens.current().startswith('--'):
+            parsed += parse_long(tokens, options)
+        elif tokens.current().startswith('-') and tokens.current() != '-':
+            parsed += parse_shorts(tokens, options)
+        elif options_first:
+            return parsed + [Argument(None, v) for v in tokens]
+        else:
+            parsed.append(Argument(None, tokens.move()))
+    return parsed
+
+
+def parse_defaults(doc):
+    defaults = []
+    for s in parse_section('options:', doc):
+        # FIXME corner case "bla: options: --foo"
+        _, _, s = s.partition(':')  # get rid of "options:"
+        split = re.split('\n[ \t]*(-\S+?)', '\n' + s)[1:]
+        split = [s1 + s2 for s1, s2 in zip(split[::2], split[1::2])]
+        options = [Option.parse(s) for s in split if s.startswith('-')]
+        defaults += options
+    return defaults
+
+
+def parse_section(name, source):
+    pattern = re.compile('^([^\n]*' + name + '[^\n]*\n?(?:[ \t].*?(?:\n|$))*)',
+                         re.IGNORECASE | re.MULTILINE)
+    return [s.strip() for s in pattern.findall(source)]
+
+
+def formal_usage(section):
+    _, _, section = section.partition(':')  # drop "usage:"
+    pu = section.split()
+    return '( ' + ' '.join(') | (' if s == pu[0] else s for s in pu[1:]) + ' )'
+
+
+def extras(help, version, options, doc):
+    if help and any((o.name in ('-h', '--help')) and o.value for o in options):
+        print(doc.strip("\n"))
+        sys.exit()
+    if version and any(o.name == '--version' and o.value for o in options):
+        print(version)
+        sys.exit()
+
+
+class Dict(dict):
+    def __repr__(self):
+        return '{%s}' % ',\n '.join('%r: %r' % i for i in sorted(self.items()))
+
+
+def docopt(doc, argv=None, help=True, version=None, options_first=False):
+    """Parse `argv` based on command-line interface described in `doc`.
+
+    `docopt` creates your command-line interface based on its
+    description that you pass as `doc`. Such description can contain
+    --options, <positional-argument>, commands, which could be
+    [optional], (required), (mutually | exclusive) or repeated...
+
+    Parameters
+    ----------
+    doc : str
+        Description of your command-line interface.
+    argv : list of str, optional
+        Argument vector to be parsed. sys.argv[1:] is used if not
+        provided.
+    help : bool (default: True)
+        Set to False to disable automatic help on -h or --help
+        options.
+    version : any object
+        If passed, the object will be printed if --version is in
+        `argv`.
+    options_first : bool (default: False)
+        Set to True to require options precede positional arguments,
+        i.e. to forbid options and positional arguments intermix.
+
+    Returns
+    -------
+    args : dict
+        A dictionary, where keys are names of command-line elements
+        such as e.g. "--verbose" and "<path>", and values are the
+        parsed values of those elements.
+
+    Example
+    -------
+    >>> from docopt import docopt
+    >>> doc = '''
+    ... Usage:
+    ...     my_program tcp <host> <port> [--timeout=<seconds>]
+    ...     my_program serial <port> [--baud=<n>] [--timeout=<seconds>]
+    ...     my_program (-h | --help | --version)
+    ...
+    ... Options:
+    ...     -h, --help  Show this screen and exit.
+    ...     --baud=<n>  Baudrate [default: 9600]
+    ... '''
+    >>> argv = ['tcp', '127.0.0.1', '80', '--timeout', '30']
+    >>> docopt(doc, argv)
+    {'--baud': '9600',
+     '--help': False,
+     '--timeout': '30',
+     '--version': False,
+     '<host>': '127.0.0.1',
+     '<port>': '80',
+     'serial': False,
+     'tcp': True}
+
+    See also
+    --------
+    * For video introduction see http://docopt.org
+    * Full documentation is available in README.rst as well as online
+      at https://github.com/docopt/docopt#readme
+
+    """
+    argv = sys.argv[1:] if argv is None else argv
+
+    usage_sections = parse_section('usage:', doc)
+    if len(usage_sections) == 0:
+        raise DocoptLanguageError('"usage:" (case-insensitive) not found.')
+    if len(usage_sections) > 1:
+        raise DocoptLanguageError('More than one "usage:" (case-insensitive).')
+    DocoptExit.usage = usage_sections[0]
+
+    options = parse_defaults(doc)
+    pattern = parse_pattern(formal_usage(DocoptExit.usage), options)
+    # [default] syntax for argument is disabled
+    #for a in pattern.flat(Argument):
+    #    same_name = [d for d in arguments if d.name == a.name]
+    #    if same_name:
+    #        a.value = same_name[0].value
+    argv = parse_argv(Tokens(argv), list(options), options_first)
+    pattern_options = set(pattern.flat(Option))
+    for options_shortcut in pattern.flat(OptionsShortcut):
+        doc_options = parse_defaults(doc)
+        options_shortcut.children = list(set(doc_options) - pattern_options)
+        #if any_options:
+        #    options_shortcut.children += [Option(o.short, o.long, o.argcount)
+        #                    for o in argv if type(o) is Option]
+    extras(help, version, argv, doc)
+    matched, left, collected = pattern.fix().match(argv)
+    if matched and left == []:  # better error message if left?
+        return Dict((a.name, a.value) for a in (pattern.flat() + collected))
+    raise DocoptExit()

extlib/libfmt/support/mkdocs

@@ -0,0 +1,76 @@
+#!/usr/bin/env python3
+# A script to invoke mkdocs with the correct environment.
+# Additionally supports deploying via mike:
+#   ./mkdocs deploy [mike-deploy-options]
+
+import errno, os, shutil, sys
+from subprocess import call
+
+support_dir = os.path.dirname(os.path.normpath(__file__))
+build_dir = os.path.join(os.path.dirname(support_dir), 'build')
+
+# Set PYTHONPATH for the mkdocstrings handler.
+env = os.environ.copy()
+path = env.get('PYTHONPATH')
+env['PYTHONPATH'] = \
+  (path + ':' if path else '') + os.path.join(support_dir, 'python')
+
+redirect_page = \
+'''<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Redirecting</title>
+  <noscript>
+    <meta http-equiv="refresh" content="1; url=11.0/" />
+  </noscript>
+  <script>
+    window.location.replace(
+      "api/" + window.location.search + window.location.hash
+    );
+  </script>
+</head>
+<body>
+  Redirecting to <a href="api/">api</a>...
+</body>
+</html>
+'''
+
+config_path = os.path.join(support_dir, 'mkdocs.yml')
+args = sys.argv[1:]
+if len(args) > 0:
+  command = args[0]
+  if command == 'deploy':
+    git_url = 'https://github.com/' if 'CI' in os.environ else 'git@github.com:'
+    site_repo = git_url + 'fmtlib/fmt.dev.git'
+
+    site_dir = os.path.join(build_dir, 'fmt.dev')
+    try:
+      shutil.rmtree(site_dir)
+    except OSError as e:
+      if e.errno == errno.ENOENT:
+        pass
+    ret = call(['git', 'clone', '--depth=1', site_repo, site_dir])
+    if ret != 0:
+      sys.exit(ret)
+
+    # Copy the config to the build dir because the site is built relative to it.
+    config_build_path = os.path.join(build_dir, 'mkdocs.yml')
+    shutil.copyfile(config_path, config_build_path)
+
+    version = args[1]
+    ret = call(['mike'] + args + ['--config-file', config_build_path,
+               '--branch', 'master'], cwd=site_dir, env=env)
+    if ret != 0 or version == 'dev':
+      sys.exit(ret)
+    redirect_page_path = os.path.join(site_dir, version, 'api.html')
+    with open(redirect_page_path, "w") as file:
+      file.write(redirect_page)
+    ret = call(['git', 'add', redirect_page_path], cwd=site_dir)
+    if ret != 0:
+      sys.exit(ret)
+    ret = call(['git', 'commit', '--amend', '--no-edit'], cwd=site_dir)
+    sys.exit(ret)
+  elif not command.startswith('-'):
+    args += ['-f', config_path]
+sys.exit(call(['mkdocs'] + args, env=env))

extlib/libfmt/support/mkdocs.yml

@@ -0,0 +1,48 @@
+site_name: '{fmt}'
+
+docs_dir: ../doc
+
+repo_url: https://github.com/fmtlib/fmt
+
+theme:
+  name: material
+  features:
+    - navigation.tabs
+    - navigation.top
+    - toc.integrate
+
+extra_javascript:
+  - https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.7.2/highlight.min.js
+  - fmt.js
+
+extra_css:
+  - https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.7.2/styles/default.min.css
+  - fmt.css
+
+markdown_extensions:
+  - pymdownx.highlight:
+      # Use JavaScript syntax highlighter instead of Pygments because it
+      # automatically applies to code blocks extracted through Doxygen.
+      use_pygments: false
+      anchor_linenums: true
+      line_spans: __span
+      pygments_lang_class: true
+  - pymdownx.inlinehilite
+  - pymdownx.snippets
+
+plugins:
+  - search
+  - mkdocstrings:
+      default_handler: cxx
+nav:
+  - Home: index.md
+  - Get Started: get-started.md
+  - API: api.md
+  - Syntax: syntax.md
+
+exclude_docs: ChangeLog-old.md
+
+extra:
+  version:
+    provider: mike
+  generator: false

extlib/libfmt/support/printable.py

@@ -0,0 +1,201 @@
+#!/usr/bin/env python3
+
+# This script is based on
+# https://github.com/rust-lang/rust/blob/master/library/core/src/unicode/printable.py
+# distributed under https://github.com/rust-lang/rust/blob/master/LICENSE-MIT.
+
+# This script uses the following Unicode tables:
+# - UnicodeData.txt
+
+
+from collections import namedtuple
+import csv
+import os
+import subprocess
+
+NUM_CODEPOINTS=0x110000
+
+def to_ranges(iter):
+    current = None
+    for i in iter:
+        if current is None or i != current[1] or i in (0x10000, 0x20000):
+            if current is not None:
+                yield tuple(current)
+            current = [i, i + 1]
+        else:
+            current[1] += 1
+    if current is not None:
+        yield tuple(current)
+
+def get_escaped(codepoints):
+    for c in codepoints:
+        if (c.class_ or "Cn") in "Cc Cf Cs Co Cn Zl Zp Zs".split() and c.value != ord(' '):
+            yield c.value
+
+def get_file(f):
+    try:
+        return open(os.path.basename(f))
+    except FileNotFoundError:
+        subprocess.run(["curl", "-O", f], check=True)
+        return open(os.path.basename(f))
+
+Codepoint = namedtuple('Codepoint', 'value class_')
+
+def get_codepoints(f):
+    r = csv.reader(f, delimiter=";")
+    prev_codepoint = 0
+    class_first = None
+    for row in r:
+        codepoint = int(row[0], 16)
+        name = row[1]
+        class_ = row[2]
+
+        if class_first is not None:
+            if not name.endswith("Last>"):
+                raise ValueError("Missing Last after First")
+
+        for c in range(prev_codepoint + 1, codepoint):
+            yield Codepoint(c, class_first)
+
+        class_first = None
+        if name.endswith("First>"):
+            class_first = class_
+
+        yield Codepoint(codepoint, class_)
+        prev_codepoint = codepoint
+
+    if class_first is not None:
+        raise ValueError("Missing Last after First")
+
+    for c in range(prev_codepoint + 1, NUM_CODEPOINTS):
+        yield Codepoint(c, None)
+
+def compress_singletons(singletons):
+    uppers = [] # (upper, # items in lowers)
+    lowers = []
+
+    for i in singletons:
+        upper = i >> 8
+        lower = i & 0xff
+        if len(uppers) == 0 or uppers[-1][0] != upper:
+            uppers.append((upper, 1))
+        else:
+            upper, count = uppers[-1]
+            uppers[-1] = upper, count + 1
+        lowers.append(lower)
+
+    return uppers, lowers
+
+def compress_normal(normal):
+    # lengths 0x00..0x7f are encoded as 00, 01, ..., 7e, 7f
+    # lengths 0x80..0x7fff are encoded as 80 80, 80 81, ..., ff fe, ff ff
+    compressed = [] # [truelen, (truelenaux), falselen, (falselenaux)]
+
+    prev_start = 0
+    for start, count in normal:
+        truelen = start - prev_start
+        falselen = count
+        prev_start = start + count
+
+        assert truelen < 0x8000 and falselen < 0x8000
+        entry = []
+        if truelen > 0x7f:
+            entry.append(0x80 | (truelen >> 8))
+            entry.append(truelen & 0xff)
+        else:
+            entry.append(truelen & 0x7f)
+        if falselen > 0x7f:
+            entry.append(0x80 | (falselen >> 8))
+            entry.append(falselen & 0xff)
+        else:
+            entry.append(falselen & 0x7f)
+
+        compressed.append(entry)
+
+    return compressed
+
+def print_singletons(uppers, lowers, uppersname, lowersname):
+    print("  static constexpr singleton {}[] = {{".format(uppersname))
+    for u, c in uppers:
+        print("    {{{:#04x}, {}}},".format(u, c))
+    print("  };")
+    print("  static constexpr unsigned char {}[] = {{".format(lowersname))
+    for i in range(0, len(lowers), 8):
+        print("    {}".format(" ".join("{:#04x},".format(l) for l in lowers[i:i+8])))
+    print("  };")
+
+def print_normal(normal, normalname):
+    print("  static constexpr unsigned char {}[] = {{".format(normalname))
+    for v in normal:
+        print("    {}".format(" ".join("{:#04x},".format(i) for i in v)))
+    print("  };")
+
+def main():
+    file = get_file("https://www.unicode.org/Public/UNIDATA/UnicodeData.txt")
+
+    codepoints = get_codepoints(file)
+
+    CUTOFF=0x10000
+    singletons0 = []
+    singletons1 = []
+    normal0 = []
+    normal1 = []
+    extra = []
+
+    for a, b in to_ranges(get_escaped(codepoints)):
+        if a > 2 * CUTOFF:
+            extra.append((a, b - a))
+        elif a == b - 1:
+            if a & CUTOFF:
+                singletons1.append(a & ~CUTOFF)
+            else:
+                singletons0.append(a)
+        elif a == b - 2:
+            if a & CUTOFF:
+                singletons1.append(a & ~CUTOFF)
+                singletons1.append((a + 1) & ~CUTOFF)
+            else:
+                singletons0.append(a)
+                singletons0.append(a + 1)
+        else:
+            if a >= 2 * CUTOFF:
+                extra.append((a, b - a))
+            elif a & CUTOFF:
+                normal1.append((a & ~CUTOFF, b - a))
+            else:
+                normal0.append((a, b - a))
+
+    singletons0u, singletons0l = compress_singletons(singletons0)
+    singletons1u, singletons1l = compress_singletons(singletons1)
+    normal0 = compress_normal(normal0)
+    normal1 = compress_normal(normal1)
+
+    print("""\
+FMT_FUNC auto is_printable(uint32_t cp) -> bool {\
+""")
+    print_singletons(singletons0u, singletons0l, 'singletons0', 'singletons0_lower')
+    print_singletons(singletons1u, singletons1l, 'singletons1', 'singletons1_lower')
+    print_normal(normal0, 'normal0')
+    print_normal(normal1, 'normal1')
+    print("""\
+  auto lower = static_cast<uint16_t>(cp);
+  if (cp < 0x10000) {
+    return is_printable(lower, singletons0,
+                        sizeof(singletons0) / sizeof(*singletons0),
+                        singletons0_lower, normal0, sizeof(normal0));
+  }
+  if (cp < 0x20000) {
+    return is_printable(lower, singletons1,
+                        sizeof(singletons1) / sizeof(*singletons1),
+                        singletons1_lower, normal1, sizeof(normal1));
+  }\
+""")
+    for a, b in extra:
+        print("  if (0x{:x} <= cp && cp < 0x{:x}) return false;".format(a, a + b))
+    print("""\
+  return cp < 0x{:x};
+}}\
+""".format(NUM_CODEPOINTS))
+
+if __name__ == '__main__':
+    main()

extlib/libfmt/support/python/mkdocstrings_handlers/cxx/__init__.py

@@ -0,0 +1,338 @@
+# A basic mkdocstrings handler for {fmt}.
+# Copyright (c) 2012 - present, Victor Zverovich
+# https://github.com/fmtlib/fmt/blob/master/LICENSE
+
+import os
+import xml.etree.ElementTree as ElementTree
+from pathlib import Path
+from subprocess import PIPE, STDOUT, CalledProcessError, Popen
+from typing import Any, List, Mapping, Optional
+
+from mkdocstrings.handlers.base import BaseHandler
+
+
+class Definition:
+    """A definition extracted by Doxygen."""
+
+    def __init__(self, name: str, kind: Optional[str] = None,
+                 node: Optional[ElementTree.Element] = None,
+                 is_member: bool = False):
+        self.name = name
+        self.kind = kind if kind is not None else node.get('kind')
+        self.desc = None
+        self.id = name if not is_member else None
+        self.members = None
+        self.params = None
+        self.template_params = None
+        self.trailing_return_type = None
+        self.type = None
+
+
+# A map from Doxygen to HTML tags.
+tag_map = {
+    'bold': 'b',
+    'emphasis': 'em',
+    'computeroutput': 'code',
+    'para': 'p',
+    'programlisting': 'pre',
+    'verbatim': 'pre'
+}
+
+# A map from Doxygen tags to text.
+tag_text_map = {
+    'codeline': '',
+    'highlight': '',
+    'sp': ' '
+}
+
+
+def escape_html(s: str) -> str:
+    return s.replace("<", "&lt;")
+
+
+def doxyxml2html(nodes: List[ElementTree.Element]):
+    out = ''
+    for n in nodes:
+        tag = tag_map.get(n.tag)
+        if not tag:
+            out += tag_text_map[n.tag]
+        out += '<' + tag + '>' if tag else ''
+        out += '<code class="language-cpp">' if tag == 'pre' else ''
+        if n.text:
+            out += escape_html(n.text)
+        out += doxyxml2html(list(n))
+        out += '</code>' if tag == 'pre' else ''
+        out += '</' + tag + '>' if tag else ''
+        if n.tail:
+            out += n.tail
+    return out
+
+
+def convert_template_params(node: ElementTree.Element) -> Optional[List[Definition]]:
+    template_param_list = node.find('templateparamlist')
+    if template_param_list is None:
+        return None
+    params = []
+    for param_node in template_param_list.findall('param'):
+        name = param_node.find('declname')
+        param = Definition(name.text if name is not None else '', 'param')
+        param.type = param_node.find('type').text
+        params.append(param)
+    return params
+
+
+def get_description(node: ElementTree.Element) -> List[ElementTree.Element]:
+    return node.findall('briefdescription/para') + \
+        node.findall('detaileddescription/para')
+
+
+def normalize_type(type_: str) -> str:
+    type_ = type_.replace('< ', '<').replace(' >', '>')
+    return type_.replace(' &', '&').replace(' *', '*')
+
+
+def convert_type(type_: ElementTree.Element) -> Optional[str]:
+    if type_ is None:
+        return None
+    result = type_.text if type_.text else ''
+    for ref in type_:
+        result += ref.text
+        if ref.tail:
+            result += ref.tail
+    result += type_.tail.strip()
+    return normalize_type(result)
+
+
+def convert_params(func: ElementTree.Element) -> List[Definition]:
+    params = []
+    for p in func.findall('param'):
+        d = Definition(p.find('declname').text, 'param')
+        d.type = convert_type(p.find('type'))
+        params.append(d)
+    return params
+
+
+def convert_return_type(d: Definition, node: ElementTree.Element) -> None:
+    d.trailing_return_type = None
+    if d.type == 'auto' or d.type == 'constexpr auto':
+        parts = node.find('argsstring').text.split(' -> ')
+        if len(parts) > 1:
+            d.trailing_return_type = normalize_type(parts[1])
+
+
+def render_param(param: Definition) -> str:
+    return param.type + (f'&nbsp;{param.name}' if len(param.name) > 0 else '')
+
+
+def render_decl(d: Definition) -> str:
+    text = ''
+    if d.id is not None:
+        text += f'<a id="{d.id}">\n'
+    text += '<pre><code class="language-cpp decl">'
+
+    text += '<div>'
+    if d.template_params is not None:
+        text += 'template &lt;'
+        text += ', '.join([render_param(p) for p in d.template_params])
+        text += '&gt;\n'
+    text += '</div>'
+
+    text += '<div>'
+    end = ';'
+    if d.kind == 'function' or d.kind == 'variable':
+        text += d.type + ' ' if len(d.type) > 0 else ''
+    elif d.kind == 'typedef':
+        text += 'using '
+    elif d.kind == 'define':
+        end = ''
+    else:
+        text += d.kind + ' '
+    text += d.name
+
+    if d.params is not None:
+        params = ', '.join([
+            (p.type + ' ' if p.type else '') + p.name for p in d.params])
+        text += '(' + escape_html(params) + ')'
+        if d.trailing_return_type:
+            text += ' -&NoBreak;>&nbsp;' + escape_html(d.trailing_return_type)
+    elif d.kind == 'typedef':
+        text += ' = ' + escape_html(d.type)
+
+    text += end
+    text += '</div>'
+    text += '</code></pre>\n'
+    if d.id is not None:
+        text += f'</a>\n'
+    return text
+
+
+class CxxHandler(BaseHandler):
+    def __init__(self, **kwargs: Any) -> None:
+        super().__init__(handler='cxx', **kwargs)
+
+        headers = [
+            'args.h', 'base.h', 'chrono.h', 'color.h', 'compile.h', 'format.h',
+            'os.h', 'ostream.h', 'printf.h', 'ranges.h', 'std.h', 'xchar.h'
+        ]
+
+        # Run doxygen.
+        cmd = ['doxygen', '-']
+        support_dir = Path(__file__).parents[3]
+        top_dir = os.path.dirname(support_dir)
+        include_dir = os.path.join(top_dir, 'include', 'fmt')
+        self._ns2doxyxml = {}
+        build_dir = os.path.join(top_dir, 'build')
+        os.makedirs(build_dir, exist_ok=True)
+        self._doxyxml_dir = os.path.join(build_dir, 'doxyxml')
+        p = Popen(cmd, stdin=PIPE, stdout=PIPE, stderr=STDOUT)
+        _, _ = p.communicate(input=r'''
+            PROJECT_NAME     = fmt
+            GENERATE_XML     = YES
+            GENERATE_LATEX   = NO
+            GENERATE_HTML    = NO
+            INPUT            = {0}
+            XML_OUTPUT       = {1}
+            QUIET            = YES
+            AUTOLINK_SUPPORT = NO
+            MACRO_EXPANSION  = YES
+            PREDEFINED       = _WIN32=1 \
+                               __linux__=1 \
+                               FMT_ENABLE_IF(...)= \
+                               FMT_USE_USER_LITERALS=1 \
+                               FMT_USE_ALIAS_TEMPLATES=1 \
+                               FMT_USE_NONTYPE_TEMPLATE_ARGS=1 \
+                               FMT_API= \
+                               "FMT_BEGIN_NAMESPACE=namespace fmt {{" \
+                               "FMT_END_NAMESPACE=}}" \
+                               "FMT_DOC=1"
+            '''.format(
+                ' '.join([os.path.join(include_dir, h) for h in headers]),
+                self._doxyxml_dir).encode('utf-8'))
+        if p.returncode != 0:
+            raise CalledProcessError(p.returncode, cmd)
+
+        # Merge all file-level XMLs into one to simplify search.
+        self._file_doxyxml = None
+        for h in headers:
+            filename = h.replace(".h", "_8h.xml")
+            with open(os.path.join(self._doxyxml_dir, filename)) as f:
+                doxyxml = ElementTree.parse(f)
+                if self._file_doxyxml is None:
+                    self._file_doxyxml = doxyxml
+                    continue
+                root = self._file_doxyxml.getroot()
+                for node in doxyxml.getroot():
+                    root.append(node)
+
+    def collect_compound(self, identifier: str,
+                         cls: List[ElementTree.Element]) -> Definition:
+        """Collect a compound definition such as a struct."""
+        path = os.path.join(self._doxyxml_dir, cls[0].get('refid') + '.xml')
+        with open(path) as f:
+            xml = ElementTree.parse(f)
+            node = xml.find('compounddef')
+            d = Definition(identifier, node=node)
+            d.template_params = convert_template_params(node)
+            d.desc = get_description(node)
+            d.members = []
+            for m in \
+                    node.findall('sectiondef[@kind="public-attrib"]/memberdef') + \
+                    node.findall('sectiondef[@kind="public-func"]/memberdef'):
+                name = m.find('name').text
+                # Doxygen incorrectly classifies members of private unnamed unions as
+                # public members of the containing class.
+                if name.endswith('_'):
+                    continue
+                desc = get_description(m)
+                if len(desc) == 0:
+                    continue
+                kind = m.get('kind')
+                member = Definition(name if name else '', kind=kind, is_member=True)
+                type_text = m.find('type').text
+                member.type = type_text if type_text else ''
+                if kind == 'function':
+                    member.params = convert_params(m)
+                    convert_return_type(member, m)
+                member.template_params = None
+                member.desc = desc
+                d.members.append(member)
+            return d
+
+    def collect(self, identifier: str, _config: Mapping[str, Any]) -> Definition:
+        qual_name = 'fmt::' + identifier
+
+        param_str = None
+        paren = qual_name.find('(')
+        if paren > 0:
+            qual_name, param_str = qual_name[:paren], qual_name[paren + 1:-1]
+
+        colons = qual_name.rfind('::')
+        namespace, name = qual_name[:colons], qual_name[colons + 2:]
+
+        # Load XML.
+        doxyxml = self._ns2doxyxml.get(namespace)
+        if doxyxml is None:
+            path = f'namespace{namespace.replace("::", "_1_1")}.xml'
+            with open(os.path.join(self._doxyxml_dir, path)) as f:
+                doxyxml = ElementTree.parse(f)
+                self._ns2doxyxml[namespace] = doxyxml
+
+        nodes = doxyxml.findall(
+            f"compounddef/sectiondef/memberdef/name[.='{name}']/..")
+        if len(nodes) == 0:
+            nodes = self._file_doxyxml.findall(
+                f"compounddef/sectiondef/memberdef/name[.='{name}']/..")
+        candidates = []
+        for node in nodes:
+            # Process a function or a typedef.
+            params = None
+            d = Definition(name, node=node)
+            if d.kind == 'function':
+                params = convert_params(node)
+                node_param_str = ', '.join([p.type for p in params])
+                if param_str and param_str != node_param_str:
+                    candidates.append(f'{name}({node_param_str})')
+                    continue
+            elif d.kind == 'define':
+                params = []
+                for p in node.findall('param'):
+                    param = Definition(p.find('defname').text, kind='param')
+                    param.type = None
+                    params.append(param)
+            d.type = convert_type(node.find('type'))
+            d.template_params = convert_template_params(node)
+            d.params = params
+            convert_return_type(d, node)
+            d.desc = get_description(node)
+            return d
+
+        cls = doxyxml.findall(f"compounddef/innerclass[.='{qual_name}']")
+        if not cls:
+            raise Exception(f'Cannot find {identifier}. Candidates: {candidates}')
+        return self.collect_compound(identifier, cls)
+
+    def render(self, d: Definition, config: dict) -> str:
+        if d.id is not None:
+            self.do_heading('', 0, id=d.id)
+        text = '<div class="docblock">\n'
+        text += render_decl(d)
+        text += '<div class="docblock-desc">\n'
+        text += doxyxml2html(d.desc)
+        if d.members is not None:
+            for m in d.members:
+                text += self.render(m, config)
+        text += '</div>\n'
+        text += '</div>\n'
+        return text
+
+
+def get_handler(theme: str, custom_templates: Optional[str] = None,
+                **_config: Any) -> CxxHandler:
+    """Return an instance of `CxxHandler`.
+
+    Arguments:
+        theme: The theme to use when rendering contents.
+        custom_templates: Directory containing custom templates.
+        **_config: Configuration passed to the handler.
+    """
+    return CxxHandler(theme=theme, custom_templates=custom_templates)

extlib/libfmt/support/python/mkdocstrings_handlers/cxx/templates/README

@@ -0,0 +1 @@
+mkdocsstrings requires a handler to have a templates directory.

extlib/libfmt/support/release.py

@@ -0,0 +1,188 @@
+#!/usr/bin/env python3
+
+"""Make a release.
+
+Usage:
+  release.py [<branch>]
+
+For the release command $FMT_TOKEN should contain a GitHub personal access token
+obtained from https://github.com/settings/tokens.
+"""
+
+from __future__ import print_function
+import datetime, docopt, errno, fileinput, json, os
+import re, shutil, sys
+from subprocess import check_call
+import urllib.request
+
+
+class Git:
+    def __init__(self, dir):
+        self.dir = dir
+
+    def call(self, method, args, **kwargs):
+        return check_call(['git', method] + list(args), **kwargs)
+
+    def add(self, *args):
+        return self.call('add', args, cwd=self.dir)
+
+    def checkout(self, *args):
+        return self.call('checkout', args, cwd=self.dir)
+
+    def clean(self, *args):
+        return self.call('clean', args, cwd=self.dir)
+
+    def clone(self, *args):
+        return self.call('clone', list(args) + [self.dir])
+
+    def commit(self, *args):
+        return self.call('commit', args, cwd=self.dir)
+
+    def pull(self, *args):
+        return self.call('pull', args, cwd=self.dir)
+
+    def push(self, *args):
+        return self.call('push', args, cwd=self.dir)
+
+    def reset(self, *args):
+        return self.call('reset', args, cwd=self.dir)
+
+    def update(self, *args):
+        clone = not os.path.exists(self.dir)
+        if clone:
+            self.clone(*args)
+        return clone
+
+
+def clean_checkout(repo, branch):
+    repo.clean('-f', '-d')
+    repo.reset('--hard')
+    repo.checkout(branch)
+
+
+class Runner:
+    def __init__(self, cwd):
+        self.cwd = cwd
+
+    def __call__(self, *args, **kwargs):
+        kwargs['cwd'] = kwargs.get('cwd', self.cwd)
+        check_call(args, **kwargs)
+
+
+def create_build_env():
+    """Create a build environment."""
+    class Env:
+        pass
+    env = Env()
+    env.fmt_dir = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+    env.build_dir = 'build'
+    env.fmt_repo = Git(os.path.join(env.build_dir, 'fmt'))
+    return env
+
+
+if __name__ == '__main__':
+    args = docopt.docopt(__doc__)
+    env = create_build_env()
+    fmt_repo = env.fmt_repo
+
+    branch = args.get('<branch>')
+    if branch is None:
+        branch = 'master'
+    if not fmt_repo.update('-b', branch, 'git@github.com:fmtlib/fmt'):
+        clean_checkout(fmt_repo, branch)
+
+    # Update the date in the changelog and extract the version and the first
+    # section content.
+    changelog = 'ChangeLog.md'
+    changelog_path = os.path.join(fmt_repo.dir, changelog)
+    is_first_section = True
+    first_section = []
+    for i, line in enumerate(fileinput.input(changelog_path, inplace=True)):
+        if i == 0:
+            version = re.match(r'# (.*) - TBD', line).group(1)
+            line = '# {} - {}\n'.format(
+                version, datetime.date.today().isoformat())
+        elif not is_first_section:
+            pass
+        elif line.startswith('#'):
+            is_first_section = False
+        else:
+            first_section.append(line)
+        sys.stdout.write(line)
+    if first_section[0] == '\n':
+        first_section.pop(0)
+
+    ns_version = None
+    base_h_path = os.path.join(fmt_repo.dir, 'include', 'fmt', 'base.h')
+    for line in fileinput.input(base_h_path):
+        m = re.match(r'\s*inline namespace v(.*) .*', line)
+        if m:
+            ns_version = m.group(1)
+            break
+    major_version = version.split('.')[0]
+    if not ns_version or ns_version != major_version:
+        raise Exception(f'Version mismatch {ns_version} != {major_version}')
+
+    # Workaround GitHub-flavored Markdown treating newlines as <br>.
+    changes = ''
+    code_block = False
+    stripped = False
+    for line in first_section:
+        if re.match(r'^\s*```', line):
+            code_block = not code_block
+            changes += line
+            stripped = False
+            continue
+        if code_block:
+            changes += line
+            continue
+        if line == '\n' or re.match(r'^\s*\|.*', line):
+            if stripped:
+                changes += '\n'
+                stripped = False
+            changes += line
+            continue
+        if stripped:
+            line = ' ' + line.lstrip()
+        changes += line.rstrip()
+        stripped = True
+
+    fmt_repo.checkout('-B', 'release')
+    fmt_repo.add(changelog)
+    fmt_repo.commit('-m', 'Update version')
+
+    # Build the docs and package.
+    run = Runner(fmt_repo.dir)
+    run('cmake', '.')
+    run('make', 'doc', 'package_source')
+
+    # Create a release on GitHub.
+    fmt_repo.push('origin', 'release')
+    auth_headers = {'Authorization': 'token ' + os.getenv('FMT_TOKEN')}
+    req = urllib.request.Request(
+        'https://api.github.com/repos/fmtlib/fmt/releases',
+        data=json.dumps({'tag_name': version,
+                         'target_commitish': 'release',
+                         'body': changes, 'draft': True}).encode('utf-8'),
+        headers=auth_headers, method='POST')
+    with urllib.request.urlopen(req) as response:
+        if response.status != 201:
+            raise Exception(f'Failed to create a release ' +
+                            '{response.status} {response.reason}')
+        response_data = json.loads(response.read().decode('utf-8'))
+        id = response_data['id']
+
+    # Upload the package.
+    uploads_url = 'https://uploads.github.com/repos/fmtlib/fmt/releases'
+    package = 'fmt-{}.zip'.format(version)
+    req = urllib.request.Request(
+        f'{uploads_url}/{id}/assets?name={package}',
+        headers={'Content-Type': 'application/zip'} | auth_headers,
+        data=open('build/fmt/' + package, 'rb').read(), method='POST')
+    with urllib.request.urlopen(req) as response:
+        if response.status != 201:
+            raise Exception(f'Failed to upload an asset '
+                            '{response.status} {response.reason}')
+
+    short_version = '.'.join(version.split('.')[:-1])
+    check_call(['./mkdocs', 'deploy', short_version])

src/amiibo-data/amiiboc.cpp

@@ -37,6 +37,9 @@ using std::vector;
 
 // libfmt
 #include <fmt/format.h>
+#ifdef _WIN32
+#  include <fmt/xchar.h>
+#endif /* !_WIN32 */
 #define FSTR FMT_STRING
 
 // tchar

src/libromdata/stdafx.h

@@ -38,6 +38,9 @@
 
 // libfmt
 #include <fmt/format.h>
+#ifdef _WIN32
+#  include <fmt/xchar.h>
+#endif /* !_WIN32 */
 #define FSTR FMT_STRING
 
 #else /* !__cplusplus */

src/libromdata/tests/RomHeaderTest.cpp

@@ -44,6 +44,9 @@ using std::string;
 
 // libfmt
 #include <fmt/format.h>
+#ifdef _WIN32
+#  include <fmt/xchar.h>
+#endif /* !_WIN32 */
 #define FSTR FMT_STRING
 
 // Uninitialized vector class