Fmt Versions Save

A modern formatting library

10.2.1

3 months ago

10.2.0

3 months ago

10.1.1

7 months ago

Added formatters for std::atomic and atomic_flag (#3574, #3594). Thanks @wangzw (Zhanwei Wang) and @AlexGuteniev (Alex Guteniev).

Fixed an error about partial specialization of formatter<string> after instantiation when compiled with gcc and C++20 (#3584).

Fixed compilation as a C++20 module with gcc and clang (#3587, #3597, #3605). Thanks @MathewBensonCode (Mathew Benson).

Made fmt::to_string work with types that have format_as overloads (#3575). Thanks @phprus (Vladislav Shchapov).

Made formatted_size work with integral format specifiers at compile time (#3591). Thanks @elbeno (Ben Deane).

Fixed a warning about the no_unique_address attribute on clang-cl (#3599). Thanks @lukester1975.

Improved compatibility with the legacy GBK encoding (#3598, #3599). Thanks @YuHuanTin.

Added OpenSSF Scorecard analysis (#3530, #3571). Thanks @joycebrum (Joyce).

Updated CI dependencies (#3591, #3592, #3593, #3602).

Pull Requests

New Contributors

10.1.0

8 months ago

Optimized format string compilation resulting in up to 40% speed up in compiled format_to and ~4x speed up in compiled format_to_n on a concatenation benchmark (#3133, #3484).

{fmt} 10.0:

---------------------------------------------------------
Benchmark               Time             CPU   Iterations
---------------------------------------------------------
BM_format_to         78.9 ns         78.9 ns      8881746
BM_format_to_n        568 ns          568 ns      1232089

{fmt} 10.1:

---------------------------------------------------------
Benchmark               Time             CPU   Iterations
---------------------------------------------------------
BM_format_to         54.9 ns         54.9 ns     12727944
BM_format_to_n        133 ns          133 ns      5257795

Optimized storage of an empty allocator in basic_memory_buffer (#3485). Thanks @Minty-Meeo.

Added formatters for proxy references to elements of std::vector<bool> and std::bitset<N> (#3567, #3570). For example (godbolt):

#include <vector>
#include <fmt/std.h>

int main() {
  auto v = std::vector<bool>{true};
  fmt::print("{}", v[0]);
}

Thanks @phprus (Vladislav Shchapov) and @felix642 (Félix-Antoine Constantin).

Fixed an ambiguous formatter specialization for containers that look like container adaptors such as boost::flat_set (#3556, #3561). Thanks @5chmidti.

Fixed compilation when formatting durations not convertible from std::chrono::seconds (#3430). Thanks @patlkli (Patrick Geltinger).

Made the formatter specialization for char* const-correct (#3432). Thanks @timsong-cpp.

Made {} and {:} handled consistently during compile-time checks (#3526).

Disallowed passing temporaries to make_format_args to improve API safety by preventing dangling references.

Improved the compile-time error for unformattable types (#3478). Thanks @BRevzin (Barry Revzin).

Improved the floating-point formatter (#3448, #3450). Thanks @florimond-collette (Florimond Collette).

Fixed handling of precision for long double larger than 64 bits. (#3539, #3564).

Made floating-point and chrono tests less platform-dependent (#3337, #3433, #3434). Thanks @phprus (Vladislav Shchapov).

Removed the remnants of the Grisu floating-point formatter that has been replaced by Dragonbox in earlier versions.

Added throw_format_error to the public API (#3551). Thanks @mjerabek (Martin Jeřábek).

Made FMT_THROW assert even if assertions are disabled when compiling with exceptions disabled (#3418, #3439). Thanks @BRevzin (Barry Revzin).

  • Added support for the ? format specifier to std::filesystem::path and made the default unescaped for consistency with strings.

Made format_as and std::filesystem::path formatter work with exotic code unit types. (#3457, #3476). Thanks @gix (Nico Rieck), @hmbj (Hans-Martin B. Jensen).

Deprecated the wide stream overload of printf.

Removed unused basic_printf_parse_context.

Improved RTTI detection used when formatting exceptions (#3468). Thanks @danakj (Dana Jansens).

Improved compatibility with VxWorks7 (#3467). Thanks @wenshan1 (Bin Lan).

Improved documentation (#3174, #3423, #3454, #3458, #3461, #3487, #3515). Thanks @zencatalyst (Kasra Hashemi), @rlalik, @mikecrowe (Mike Crowe).

Improved build and CI configurations (#3449, #3451, #3452, #3453, #3459, #3481, #3486, #3489, #3496, #3517, #3523, #3563). Thanks @joycebrum (Joyce), @glebm (Gleb Mazovetskiy), @phprus (Vladislav Shchapov), @petrmanek (Petr Mánek), @setoye (Alta), @abouvier (Alexandre Bouvier).

Fixed various warnings and compilation issues (#3408, #3424, #3444, #3446, #3475, #3482, #3492, #3493, #3508, #3509, #3533, #3542, #3543, #3540, #3544, #3548, #3549, #3550, #3552). Thanks @adesitter (Arnaud Desitter), @hmbj (Hans-Martin B. Jensen), @Minty-Meeo, @phprus (Vladislav Shchapov), @TobiSchluter (Tobias Schlüter), @kieranclancy (Kieran Clancy), @alexeedm (Dmitry Alexeev), @jurihock (Jürgen Hock), @Ozomahtli, @razaqq.

Pull Requests

New Contributors

10.0.0

11 months ago

Replaced Grisu with a new floating-point formatting algorithm for given precision (#3262, #2750, #3269, #3276). The new algorithm is based on Dragonbox already used for the shortest representation and gives substantial performance improvement:

Red: new algorithm

Green: new algorithm with `FMT_USE_FULL_CACHE_DRAGONBOX` defined to 1

Blue: old algorithm

Thanks @jk-jeon (Junekey Jeon).

Replaced snprintf-based hex float formatter with an internal implementation (#3179, #3203). This removes the last usage of s(n)printf in {fmt}. Thanks @phprus (Vladislav Shchapov).

Fixed alignment of floating-point numbers with localization (#3263, #3272). Thanks @ShawnZhong (Shawn Zhong).

  • Made handling of # consistent with std::format.

Improved C++20 module support (#3134, #3254, #3386, #3387, #3388, #3392, #3397, #3399, #3400). Thanks @laitingsheng (Tinson Lai), @Orvid (Orvid King), @DanielaE (Daniela Engert). Switched to the modules CMake library which allows building {fmt} as a C++20 module with clang:

CXX=clang++ cmake -DFMT_MODULE=ON .
make

Made format_as work with any user-defined type and not just enums. For example (godbolt):

#include <fmt/format.h>

struct floaty_mc_floatface {
  double value;
};

auto format_as(floaty_mc_floatface f) { return f.value; }

int main() {
  fmt::print("{:8}\n", floaty_mc_floatface{0.42}); // prints "    0.42"
}

Removed deprecated implicit conversions for enums and conversions to primitive types for compatibility with std::format and to prevent potential ODR violations. Use format_as instead.

Added support for fill, align and width to the time point formatter (#3237, #3260, #3275). For example (godbolt):

#include <fmt/chrono.h>

int main() {
  // prints "    2023"
  fmt::print("{:>8%Y}\n", std::chrono::system_clock::now());
}

Thanks @ShawnZhong (Shawn Zhong).

Implemented formatting of subseconds (#2207, #3117, #3115, #3143, #3144, #3349). For example (godbolt):

#include <fmt/chrono.h>

int main() {
  // prints 01.234567
  fmt::print("{:%S}\n", std::chrono::microseconds(1234567));
}

Thanks @patrickroocks (Patrick Roocks) @phprus (Vladislav Shchapov), @BRevzin (Barry Revzin).

Added precision support to %S (#3148). Thanks @SappyJoy (Stepan Ponomaryov)

Added support for std::utc_time (#3098, #3110). Thanks @patrickroocks (Patrick Roocks).

Switched formatting of std::chrono::system_clock from local time to UTC for compatibility with the standard (#3199, #3230). Thanks @ned14 (Niall Douglas).

Added support for %Ez and %Oz to chrono formatters. (#3220, #3222). Thanks @phprus (Vladislav Shchapov).

Improved validation of format specifiers for std::chrono::duration (#3219, #3232). Thanks @ShawnZhong (Shawn Zhong).

Fixed formatting of time points before the epoch (#3117, #3261). For example (godbolt):

#include <fmt/chrono.h>

int main() {
  auto t = std::chrono::system_clock::from_time_t(0) -
           std::chrono::milliseconds(250);
  fmt::print("{:%S}\n", t); // prints 59.750000000
}

Thanks @ShawnZhong (Shawn Zhong).

Experimental: implemented glibc extension for padding seconds, minutes and hours (#2959, #3271). Thanks @ShawnZhong (Shawn Zhong).

Added a formatter for std::exception (#2977, #3012, #3062, #3076, #3119). For example (godbolt):

#include <fmt/std.h>
#include <vector>

int main() {
  try {
    std::vector<bool>().at(0);
  } catch(const std::exception& e) {
    fmt::print("{}", e);
  }
}

prints:

vector<bool>::_M_range_check: __n (which is 0) >= this->size() (which is 0)

on libstdc++. Thanks @zach2good (Zach Toogood) and @phprus (Vladislav Shchapov).

Moved std::error_code formatter from fmt/os.h to fmt/std.h. (#3125). Thanks @phprus (Vladislav Shchapov).

Added formatters for standard container adapters: std::priority_queue, std::queue and std::stack (#3215, #3279). For example (godbolt):

#include <fmt/ranges.h>
#include <stack>
#include <vector>

int main() {
  auto s = std::stack<bool, std::vector<bool>>();
  for (auto b: {true, false, true}) s.push(b);
  fmt::print("{}\n", s); // prints [true, false, true]
}

Thanks @ShawnZhong (Shawn Zhong).

Added a formatter for std::optional to fmt/std.h. Thanks @tom-huntington.

Fixed formatting of valueless by exception variants (#3347). Thanks @TheOmegaCarrot.

Made fmt::ptr accept unique_ptr with a custom deleter (#3177). Thanks @hmbj (Hans-Martin B. Jensen).

Fixed formatting of noncopyable ranges and nested ranges of chars (#3158 #3286, #3290). Thanks @BRevzin (Barry Revzin).

Fixed issues with formatting of paths and ranges of paths (#3319, #3321 #3322). Thanks @phprus (Vladislav Shchapov).

Improved handling of invalid Unicode in paths.

Enabled compile-time checks on Apple clang 14 and later (#3331). Thanks @cloyce (Cloyce D. Spradling).

Improved compile-time checks of named arguments (#3105, #3214). Thanks @rbrich (Radek Brich).

Fixed formatting when both alignment and 0 are given (#3236, #3248). Thanks @ShawnZhong (Shawn Zhong).

Improved Unicode support in the experimental file API on Windows (#3234, #3293). Thanks @Fros1er (Froster).

Unified UTF transcoding (#3416). Thanks @phprus (Vladislav Shchapov).

Added support for UTF-8 digit separators via an experimental locale facet (#1861). For example (godbolt):

auto loc = std::locale(
  std::locale(), new fmt::format_facet<std::locale>("’"));
auto s = fmt::format(loc, "{:L}", 1000);

where ’ is U+2019 used as a digit separator in the de_CH locale.

Added an overload of formatted_size that takes a locale (#3084, #3087). Thanks @gerboengels.

Removed the deprecated FMT_DEPRECATED_OSTREAM.

Fixed a UB when using a null std::string_view with fmt::to_string or format string compilation (#3241, #3244). Thanks @phprus (Vladislav Shchapov).

Added starts_with to the fallback string_view implementation (#3080). Thanks @phprus (Vladislav Shchapov).

Added fmt::basic_format_string::get() for compatibility with basic_format_string (#3111). Thanks @huangqinjin.

Added println for compatibility with C++23 (#3267). Thanks @ShawnZhong (Shawn Zhong).

  • Renamed the FMT_EXPORT macro for shared library usage to FMT_LIB_EXPORT.

  • Improved documentation (#3108, #3169, #3243). #3404). Thanks @Cleroth and @Vertexwahn.

Improved build configuration and tests (#3118, #3120, #3188, #3189, #3198, #3205, #3207, #3210, #3240, #3256, #3264, #3299, #3302, #3312, #3317, #3328, #3333, #3369, #3373, #3395, #3406, #3411). Thanks @dimztimz (Dimitrij Mijoski), @phprus (Vladislav Shchapov), @DavidKorczynski, @ChrisThrasher (Chris Thrasher), @FrancoisCarouge (François Carouge), @kennyweiss (Kenny Weiss), @luzpaz, @codeinred (Alecto Irene Perez), @Mixaill (Mikhail Paulyshka), @joycebrum (Joyce), @kevinhwang (Kevin Hwang), @Vertexwahn.

Fixed a regression in handling empty format specifiers after a colon ({:}) (#3086). Thanks @oxidase (Michael Krasnyk).

Worked around a broken implementation of std::is_constant_evaluated in some versions of libstdc++ on clang (#3247, #3281). Thanks @phprus (Vladislav Shchapov).

Fixed formatting of volatile variables (#3068).

Fixed various warnings and compilation issues (#3057, #3066, #3072, #3082, #3091, #3092, #3093, #3095, #3096, #3097, #3128, #3129, #3137, #3139, #3140, #3142, #3149, #3150, #3154, #3163, #3178, #3184, #3196, #3204, #3206, #3208, #3213, #3216, #3224, #3226, #3228, #3229, #3259, #3274, #3287, #3288, #3292, #3295, #3296, #3298, #3325, #3326, #3334, #3342, #3343, #3351, #3352, #3362, #3365, #3366, #3374, #3377, #3378, #3381, #3398, #3413, #3415). Thanks @phprus (Vladislav Shchapov), @gsjaardema (Greg Sjaardema), @NewbieOrange, @EngineLessCC (VivyaCC), @asmaloney (Andy Maloney), @HazardyKnusperkeks (Björn Schäpers), @sergiud (Sergiu Deitsch), @Youw (Ihor Dutchak), @thesmurph, @czudziakm (Maksymilian Czudziak), @Roman-Koshelev, @chronoxor (Ivan Shynkarenka), @ShawnZhong (Shawn Zhong), @russelltg (Russell Greene), @glebm (Gleb Mazovetskiy), @tmartin-gh, @Zhaojun-Liu (June Liu), @louiswins (Louis Wilson), @mogemimi.

Pull Requests

New Contributors

Full Changelog: https://github.com/fmtlib/fmt/compare/9.1.0...10.0.0

9.1.0

1 year ago

fmt::formatted_size now works at compile time (#3026). For example (godbolt):

#include <fmt/compile.h>

int main() {
  using namespace fmt::literals;
  constexpr size_t n = fmt::formatted_size("{}"_cf, 42);
  fmt::print("{}\n", n); // prints 2
}

Thanks @marksantaniello (Mark Santaniello).

Fixed handling of invalid UTF-8 (#3038, #3044, #3056). Thanks @phprus (Vladislav Shchapov) and @skeeto (Christopher Wellons).

Improved Unicode support in ostream overloads of print (#2994, #3001, #3025). Thanks @dimztimz (Dimitrij Mijoski).

Fixed handling of the sign specifier in localized formatting on systems with 32-bit wchar_t (#3041).

Added support for wide streams to fmt::streamed (#2994). Thanks @phprus (Vladislav Shchapov).

Added the n specifier that disables the output of delimiters when formatting ranges (#2981, #2983). For example (godbolt):

#include <fmt/ranges.h>
#include <vector>

int main() {
  auto v = std::vector{1, 2, 3};
  fmt::print("{:n}\n", v); // prints 1, 2, 3
}

Thanks @BRevzin (Barry Revzin).

Worked around problematic std::string_view constructors introduced in C++23 (#3030, #3050). Thanks @strega-nil-ms (nicole mazzuca).

Improve handling (exclusion) of recursive ranges (#2968, #2974). Thanks @Dani-Hub (Daniel Krügler).

Improved error reporting in format string compilation (#3055).

Improved the implementation of Dragonbox, the algorithm used for the default floating-point formatting (#2984). Thanks @jk-jeon (Junekey Jeon).

Fixed issues with floating-point formatting on exotic platforms.

Improved the implementation of chrono formatting (#3010). Thanks @phprus (Vladislav Shchapov).

Improved documentation (#2966, #3009, #3020, #3037). Thanks @mwinterb, @jcelerier (Jean-Michaël Celerier) and @remiburtin (Rémi Burtin).

Improved build configuration (#2991, #2995, #3004, #3007, #3040). Thanks @dimztimz (Dimitrij Mijoski) and @hwhsu1231 (Haowei Hsu).

Fixed various warnings and compilation issues (#2969, #2971, #2975, #2982, #2985, #2988, #3000, #3006, #3014, #3015, #3021, #3023, #3024, #3029, #3043, #3052, #3053, #3054). Thanks @h-friederich (Hannes Friederich), @dimztimz (Dimitrij Mijoski), @olupton (Olli Lupton), @bernhardmgruber (Bernhard Manfred Gruber), @phprus (Vladislav Shchapov).

Pull Requests

New Contributors

Full Changelog: https://github.com/fmtlib/fmt/compare/9.0.0...9.1.0

9.0.0

1 year ago

Switched to the internal floating point formatter for all decimal presentation formats. In particular this results in consistent rounding on all platforms and removing the s[n]printf fallback for decimal FP formatting.

Compile-time floating point formatting no longer requires the header-only mode. For example (godbolt):

#include <array>
#include <fmt/compile.h>

consteval auto compile_time_dtoa(double value) -> std::array<char, 10> {
  auto result = std::array<char, 10>();
  fmt::format_to(result.data(), FMT_COMPILE("{}"), value);
  return result;
}

constexpr auto answer = compile_time_dtoa(0.42);

works with the default settings.

Improved the implementation of Dragonbox, the algorithm used for the default floating-point formatting (#2713, #2750). Thanks @jk-jeon (Junekey Jeon).

Made fmt::to_string work with __float128. This uses the internal FP formatter and works even on system without __float128 support in [s]printf.

Disabled automatic std::ostream insertion operator (operator<<) discovery when fmt/ostream.h is included to prevent ODR violations. You can get the old behavior by defining FMT_DEPRECATED_OSTREAM but this will be removed in the next major release. Use fmt::streamed or fmt::ostream_formatter to enable formatting via std::ostream instead.

Added fmt::ostream_formatter that can be used to write formatter specializations that perform formatting via std::ostream. For example (godbolt):

#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"

Added the fmt::streamed function that takes an object and formats it via std::ostream. For example (godbolt):

#include <thread>
#include <fmt/ostream.h>

int main() {
  fmt::print("Current thread id: {}\n",
             fmt::streamed(std::this_thread::get_id()));
}

Note that fmt/std.h provides a formatter specialization for std::thread::id so you don't need to format it via std::ostream.

Deprecated implicit conversions of unscoped enums to integers for consistency with scoped enums.

Added an argument-dependent lookup based format_as extension API to simplify formatting of enums.

Added experimental std::variant formatting support (#2941). For example (godbolt):

#include <variant>
#include <fmt/std.h>

int main() {
  auto v = std::variant<int, std::string>(42);
  fmt::print("{}\n", v);
}

prints:

variant(42)

Thanks @jehelset.

Added experimental std::filesystem::path formatting support (#2865, #2902, #2917, #2918). For example (godbolt):

#include <filesystem>
#include <fmt/std.h>

int main() {
  fmt::print("There is no place like {}.", std::filesystem::path("/home"));
}

prints:

There is no place like "/home".

Thanks @phprus (Vladislav Shchapov).

Added a std::thread::id formatter to fmt/std.h. For example (godbolt):

#include <thread>
#include <fmt/std.h>

int main() {
  fmt::print("Current thread id: {}\n", std::this_thread::get_id());
}

Added fmt::styled that applies a text style to an individual argument (#2793). For example (godbolt):

#include <fmt/chrono.h>
#include <fmt/color.h>

int main() {
  auto now = std::chrono::system_clock::now();
  fmt::print(
    "[{}] {}: {}\n",
    fmt::styled(now, fmt::emphasis::bold),
    fmt::styled("error", fg(fmt::color::red)),
    "something went wrong");
}

prints

Thanks @rbrugo (Riccardo Brugo).

Made fmt::print overload for text styles correctly handle UTF-8 (#2681, #2701). Thanks @AlexGuteniev (Alex Guteniev).

Fixed Unicode handling when writing to an ostream.

Added support for nested specifiers to range formatting (#2673). For example (godbolt):

#include <vector>
#include <fmt/ranges.h>

int main() {
  fmt::print("{::#x}\n", std::vector{10, 20, 30});
}

prints [0xa, 0x14, 0x1e].

Thanks @BRevzin (Barry Revzin).

Implemented escaping of wide strings in ranges (#2904). Thanks @phprus (Vladislav Shchapov).

Added support for ranges with begin / end found via the argument-dependent lookup (#2807). Thanks @rbrugo (Riccardo Brugo).

Fixed formatting of certain kinds of ranges of ranges (#2787). Thanks @BRevzin (Barry Revzin).

Fixed handling of maps with element types other than std::pair (#2944). Thanks @BrukerJWD (Jonathan W).

Made tuple formatter enabled only if elements are formattable (#2939, #2940). Thanks @jehelset.

Made fmt::join compatible with format string compilation (#2719, #2720). Thanks @phprus (Vladislav Shchapov).

Made compile-time checks work with named arguments of custom types and std::ostream print overloads (#2816, #2817, #2819). Thanks @timsong-cpp.

Removed make_args_checked because it is no longer needed for compile-time checks (#2760). Thanks @phprus (Vladislav Shchapov).

Removed the following deprecated APIs: _format, arg_join, the format_to overload that takes a memory buffer, [v]fprintf that takes an ostream.

Removed the deprecated implicit conversion of [const] signed char* and [const] unsigned char* to C strings.

Removed the deprecated fmt/locale.h.

Replaced the deprecated fileno() with descriptor() in buffered_file.

Moved to_string_view to the detail namespace since it's an implementation detail.

Made access mode of a created file consistent with fopen by setting S_IWGRP and S_IWOTH (#2733). Thanks @arogge (Andreas Rogge).

Removed a redundant buffer resize when formatting to std::ostream (#2842, #2843). Thanks @jcelerier (Jean-Michaël Celerier).

Made precision computation for strings consistent with width (#2888).

Fixed handling of locale separators in floating point formatting (#2830).

Made sign specifiers work with __int128_t (#2773).

Improved support for systems such as CHERI with extra data stored in pointers (#2932). Thanks @davidchisnall (David Chisnall).

Improved documentation (#2706, #2712, #2789, #2803, #2805, #2815, #2924). Thanks @BRevzin (Barry Revzin), @Pokechu22, @setoye (Alta), @rtobar, @rbrugo (Riccardo Brugo), @anoonD (cre), @leha-bot (Alex).

Improved build configuration (#2766, #2772, #2836, #2852, #2907, #2913, #2914). Thanks @kambala-decapitator (Andrey Filipenkov), @mattiasljungstrom (Mattias Ljungström), @kieselnb (Nick Kiesel), @nathannaveen, @Vertexwahn.

Fixed various warnings and compilation issues (#2408, #2507, #2697, #2715, #2717, #2722, #2724, #2725, #2726, #2728, #2732, #2738, #2742, #2744, #2745, #2746, #2754, #2755, #2757, #2758, #2761, #2762, #2763, #2765, #2769, #2770, #2771, #2777, #2779, #2782, #2783, #2794, #2796, #2797, #2801, #2802, #2808, #2818, #2819, #2829, #2835, #2848, #2860, #2861, #2882, #2886, #2891, #2892, #2895, #2896, #2903, #2906, #2908, #2909, #2920, #2922, #2927, #2929, #2936, #2937, #2938, #2951, #2954, #2957, #2958, #2960). Thanks @matrackif @Tobi823 (Tobias Hellmann), @ivan-volnov (Ivan Volnov), @VasiliPupkin256, @federico-busato (Federico), @barcharcraz (Charlie Barto), @jk-jeon (Junekey Jeon), @HazardyKnusperkeks (Björn Schäpers), @dalboris (Boris Dalstein), @seanm (Sean McBride), @gsjaardema (Greg Sjaardema), @timsong-cpp, @seanm (Sean McBride), @frithrah, @chronoxor (Ivan Shynkarenka), @Agga, @madmaxoft (Mattes D), @JurajX (Juraj), @phprus (Vladislav Shchapov), @Dani-Hub (Daniel Krügler).

Pull Requests

New Contributors

Full Changelog: https://github.com/fmtlib/fmt/compare/8.1.1...9.0.0

8.1.1

2 years ago

Restored ABI compatibility with version 8.0.x (#2695, #2696). Thanks @saraedum (Julian Rüth).

Fixed chrono formatting on big endian systems (#2698, #2699). Thanks @phprus (Vladislav Shchapov) and @xvitaly (Vitaly Zaitsev).

Fixed a linkage error with mingw (#2691, #2692). Thanks @rbberger (Richard Berger).

8.1.0

2 years ago

Optimized chrono formatting (#2500, #2537, #2541, #2544, #2550, #2551, #2576, #2577, #2586, #2591, #2594, #2602, #2617, #2628, #2633, #2670, #2671).

Processing of some specifiers such as %z and %Y is now up to 10-20 times faster, for example on GCC 11 with libstdc++:

----------------------------------------------------------------------------
Benchmark                                  Before             After
----------------------------------------------------------------------------
FMTFormatter_z                             261 ns             26.3 ns
FMTFormatterCompile_z                      246 ns             11.6 ns
FMTFormatter_Y                             263 ns             26.1 ns
FMTFormatterCompile_Y                      244 ns             10.5 ns
----------------------------------------------------------------------------

Thanks @phprus (Vladislav Shchapov) and @toughengineer (Pavel Novikov).

Implemented subsecond formatting for chrono durations (#2623). For example (godbolt):

#include <fmt/chrono.h>

int main() {
  fmt::print("{:%S}", std::chrono::milliseconds(1234));
}

prints "01.234".

Thanks @matrackif.

Fixed handling of precision 0 when formatting chrono durations (#2587, #2588). Thanks @lukester1975.

Fixed an overflow on invalid inputs in the tm formatter (#2564). Thanks @phprus (Vladislav Shchapov).

Added fmt::group_digits that formats integers with a non-localized digit separator (comma) for groups of three digits. For example (godbolt):

#include <fmt/format.h>

int main() {
  fmt::print("{} dollars", fmt::group_digits(1000000));
}

prints "1,000,000 dollars".

Added support for faint, conceal, reverse and blink text styles (#2394):

https://user-images.githubusercontent.com/576385/147710227-c68f5317-f8fa-42c3-9123-7c4ba3c398cb.mp4

Thanks @benit8 (Benoît Lormeau) and @data-man (Dmitry Atamanov).

Added experimental support for compile-time floating point formatting (#2426, #2470). It is currently limited to the header-only mode. Thanks @alexezeder (Alexey Ochapov).

Added UDL-based named argument support to compile-time format string checks (#2640, #2649). For example (godbolt):

#include <fmt/format.h>

int main() {
  using namespace fmt::literals;
  fmt::print("{answer:s}", "answer"_a=42);
}

gives a compile-time error on compilers with C++20 consteval and non-type template parameter support (gcc 10+) because s is not a valid format specifier for an integer.

Thanks @alexezeder (Alexey Ochapov).

Implemented escaping of string range elements. For example (godbolt):

#include <fmt/ranges.h>
#include <vector>

int main() {
  fmt::print("{}", std::vector<std::string>{"\naan"});
}

is now printed as:

["\naan"]

instead of:

["
aan"]

Switched to JSON-like representation of maps and sets for consistency with Python's str.format. For example (godbolt):

#include <fmt/ranges.h>
#include <map>

int main() {
  fmt::print("{}", std::map<std::string, int>{{"answer", 42}});
}

is now printed as:

{"answer": 42}

Extended fmt::join to support C++20-only ranges (#2549). Thanks @BRevzin (Barry Revzin).

Optimized handling of non-const-iterable ranges and implemented initial support for non-const-formattable types.

Disabled implicit conversions of scoped enums to integers that was accidentally introduced in earlier versions (#1841).

Deprecated implicit conversion of [const] signed char* and [const] unsigned char* to C strings.

Deprecated _format, a legacy UDL-based format API (#2646). Thanks @alexezeder (Alexey Ochapov).

Marked format, formatted_size and to_string as [[nodiscard]] (#2612). @0x8000-0000 (Florin Iucha).

Added missing diagnostic when trying to format function and member pointers as well as objects convertible to pointers which is explicitly disallowed (#2598, #2609, #2610). Thanks @AlexGuteniev (Alex Guteniev).

Optimized writing to a contiguous buffer with format_to_n (#2489). Thanks @Roman-Koshelev.

Optimized writing to non-char buffers (#2477). Thanks @Roman-Koshelev.

Decimal point is now localized when using the L specifier.

Improved floating point formatter implementation (#2498, #2499). Thanks @Roman-Koshelev.

Fixed handling of very large precision in fixed format (#2616).

Made a table of cached powers used in FP formatting static (#2509). Thanks @jk-jeon (Junekey Jeon).

Resolved a lookup ambiguity with C++20 format-related functions due to ADL (#2639, #2641). Thanks @mkurdej (Marek Kurdej).

Removed unnecessary inline namespace qualification (#2642, #2643). Thanks @mkurdej (Marek Kurdej).

Implemented argument forwarding in format_to_n (#2462, #2463). Thanks @owent (WenTao Ou).

Fixed handling of implicit conversions in fmt::to_string and format string compilation (#2565).

Changed the default access mode of files created by fmt::output_file to -rw-r--r-- for consistency with fopen (#2530).

Make fmt::ostream::flush public (#2435).

Improved C++14/17 attribute detection (#2615). Thanks @AlexGuteniev (Alex Guteniev).

Improved consteval detection for MSVC (#2559). Thanks @DanielaE (Daniela Engert).

Improved documentation (#2406, #2446, #2493, #2513, #2515, #2522, #2562, #2575, #2606, #2620, #2676). Thanks @sobolevn (Nikita Sobolev), @UnePierre (Max FERGER), @zhsj, @phprus (Vladislav Shchapov), @ericcurtin (Eric Curtin), @Lounarok.

Improved fuzzers and added a fuzzer for chrono timepoint formatting (#2461, #2469). @pauldreik (Paul Dreik),

Added the FMT_SYSTEM_HEADERS CMake option setting which marks {fmt}'s headers as system. It can be used to suppress warnings (#2644, #2651). Thanks @alexezeder (Alexey Ochapov).

Added the Bazel build system support (#2505, #2516). Thanks @Vertexwahn.

Improved build configuration and tests (#2437, #2558, #2648, #2650, #2663, #2677). Thanks @DanielaE (Daniela Engert), @alexezeder (Alexey Ochapov), @phprus (Vladislav Shchapov).

Fixed various warnings and compilation issues (#2353, #2356, #2399, #2408, #2414, #2427, #2432, #2442, #2434, #2439, #2447, #2450, #2455, #2465, #2472, #2474, #2476, #2478, #2479, #2481, #2482, #2483, #2490, #2491, #2510, #2518, #2528, #2529, #2539, #2540, #2545, #2555, #2557, #2570, #2573, #2582, #2605, #2611, #2647, #2627, #2630, #2635, #2638, #2653, #2654, #2661, #2664, #2684). Thanks @DanielaE (Daniela Engert), @mwinterb, @cdacamar (Cameron DaCamara), @TrebledJ (Johnathan), @bodomartin (brm), @cquammen (Cory Quammen), @white238 (Chris White), @mmarkeloff (Max), @palacaze (Pierre-Antoine Lacaze), @jcelerier (Jean-Michaël Celerier), @mborn-adi (Mathias Born), @BrukerJWD (Jonathan W), @spyridon97 (Spiros Tsalikis), @phprus (Vladislav Shchapov), @oliverlee (Oliver Lee), @joshessman-llnl (Josh Essman), @akohlmey (Axel Kohlmeyer), @timkalu, @olupton (Olli Lupton), @Acretock, @alexezeder (Alexey Ochapov), @andrewcorrigan (Andrew Corrigan), @lucpelletier, @HazardyKnusperkeks (Björn Schäpers).

8.0.1

2 years ago

Fixed the version number in the inline namespace (#2374).

Added a missing presentation type check for std::string (#2402).

Fixed a linkage error when mixing code built with clang and gcc (#2377).

Fixed documentation issues (#2396, #2403, #2406). Thanks @mkurdej (Marek Kurdej).

Removed dead code in FP formatter ( #2398). Thanks @javierhonduco (Javier Honduvilla Coto).

Fixed various warnings and compilation issues (#2351, #2359, #2365, #2368, #2370, #2376, #2381, #2382, #2386, #2389, #2395, #2397, #2400 #2401, #2407). Thanks @zx2c4 (Jason A. Donenfeld), @AidanSun05 (Aidan Sun), @mattiasljungstrom (Mattias Ljungström), @joemmett (Jonathan Emmett), @erengy (Eren Okka), @patlkli (Patrick Geltinger), @gsjaardema (Greg Sjaardema), @phprus (Vladislav Shchapov).