196 KiB
10.2.0 - TBD
-
Added support for the
%j
specifier (the number of days) forstd::chrono::duration
(https://github.com/fmtlib/fmt/issues/3643, https://github.com/fmtlib/fmt/pull/3732). Thanks @intelfx. -
Added support for the chrono suffix for days and changed the suffix for minutes from "m" to the correct "min" (https://github.com/fmtlib/fmt/issues/3662, https://github.com/fmtlib/fmt/pull/3664). For example (godbolt):
#include <fmt/chrono.h> int main() { fmt::print("{}\n", std::chrono::days(42)); // prints "42d" }
Thanks @Richardk2n.
-
Fixed an overflow in
std::chrono::time_point
formatting with large dates (https://github.com/fmtlib/fmt/issues/3725, https://github.com/fmtlib/fmt/pull/3727). Thanks @cschreib. -
Added a formatter for
std::source_location
(https://github.com/fmtlib/fmt/pull/3730). For example (godbolt):#include <source_location> #include <fmt/std.h> int main() { fmt::print("{}\n", std::source_location::current()); }
prints
/app/example.cpp:5:51: int main()
Thanks @felix642.
-
Added a formatter for
std::bitset
(https://github.com/fmtlib/fmt/pull/3660). For example (godbolt):#include <bitset> #include <fmt/std.h> int main() { fmt::print("{}\n", std::bitset<6>(42)); // prints "101010" }
Thanks @muggenhor.
-
Added an experimental
nested_formatter
that provides an easy way of applying a formatter to one or more subobjects while automatically handling width, fill and alignment. 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, "({}, {})", nested(p.x), nested(p.y)); }); } }; int main() { fmt::print("[{:>20.2f}]", point{1, 2}); }
prints
[ (1.00, 2.00)]
-
Added the generic representation (
g
) tostd::filesystem::path
(https://github.com/fmtlib/fmt/issues/3715, https://github.com/fmtlib/fmt/pull/3729). For example:#include <filesystem> #include <fmt/std.h> int main() { fmt::print("{:g}\n", std::filesystem::path("C:\\foo")); }
prints
"C:/foo"
on Windows.Thanks @js324.
-
Made
format_as
work with references (https://github.com/fmtlib/fmt/pull/3739). Thanks @tchaikov. -
Fixed formatting of invalid UTF-8 with precision (https://github.com/fmtlib/fmt/issues/3284).
-
Fixed an inconsistency between
fmt::to_string
andfmt::format
(https://github.com/fmtlib/fmt/issues/3684). -
Disallowed unsafe uses of
fmt::styled
(https://github.com/fmtlib/fmt/issues/3625):auto s = fmt::styled(std::string("dangler"), fmt::emphasis::bold); fmt::print("{}\n", s); // compile error
Pass
fmt::styled(...)
as a parameter instead. -
Added a null check when formatting C strings with the
s
specifier (https://github.com/fmtlib/fmt/issues/3706). -
Disallowed the
c
specifier forbool
(https://github.com/fmtlib/fmt/issues/3726, https://github.com/fmtlib/fmt/pull/3734). Thanks @js324. -
Made the default formatting unlocalized in
fmt::ostream_formatter
for consistency with the rest of the library (https://github.com/fmtlib/fmt/issues/3460). -
Fixed localized formatting in bases other than decimal (https://github.com/fmtlib/fmt/issues/3693, https://github.com/fmtlib/fmt/pull/3750). Thanks @js324.
-
Fixed a performance regression in experimental
fmt::ostream::print
(https://github.com/fmtlib/fmt/issues/3674). -
Added synchronization with the underlying output stream when writing to the Windows console (https://github.com/fmtlib/fmt/pull/3668, https://github.com/fmtlib/fmt/issues/3688, https://github.com/fmtlib/fmt/pull/3689). Thanks @Roman-Koshelev and @dimztimz.
-
Changed to only export
format_error
when {fmt} is built as a shared library (https://github.com/fmtlib/fmt/issues/3626, https://github.com/fmtlib/fmt/pull/3627). Thanks @phprus. -
Made
fmt::streamed
constexpr
. (https://github.com/fmtlib/fmt/pull/3650). Thanks @muggenhor. -
Enabled
consteval
on older versions of MSVC (https://github.com/fmtlib/fmt/pull/3757). Thanks @phprus. -
Added an option to build without
wchar_t
support on Windows (https://github.com/fmtlib/fmt/issues/3631, https://github.com/fmtlib/fmt/pull/3636). Thanks @glebm. -
Improved build and CI configuration (https://github.com/fmtlib/fmt/pull/3679, https://github.com/fmtlib/fmt/issues/3701, https://github.com/fmtlib/fmt/pull/3702, https://github.com/fmtlib/fmt/pull/3749). Thanks @jcar87, @pklima and @tchaikov.
-
Fixed various warnings, compilation and test issues (https://github.com/fmtlib/fmt/issues/3607, https://github.com/fmtlib/fmt/pull/3610, https://github.com/fmtlib/fmt/pull/3624, https://github.com/fmtlib/fmt/pull/3630, https://github.com/fmtlib/fmt/pull/3634, https://github.com/fmtlib/fmt/pull/3638, https://github.com/fmtlib/fmt/issues/3645, https://github.com/fmtlib/fmt/issues/3646, https://github.com/fmtlib/fmt/pull/3647, https://github.com/fmtlib/fmt/pull/3652, https://github.com/fmtlib/fmt/issues/3654, https://github.com/fmtlib/fmt/pull/3663, https://github.com/fmtlib/fmt/issues/3670, https://github.com/fmtlib/fmt/pull/3680, https://github.com/fmtlib/fmt/issues/3694, https://github.com/fmtlib/fmt/pull/3695, https://github.com/fmtlib/fmt/pull/3699, https://github.com/fmtlib/fmt/issues/3705, https://github.com/fmtlib/fmt/issues/3710, https://github.com/fmtlib/fmt/issues/3712, https://github.com/fmtlib/fmt/pull/3713, https://github.com/fmtlib/fmt/issues/3714, https://github.com/fmtlib/fmt/pull/3716, https://github.com/fmtlib/fmt/pull/3723, https://github.com/fmtlib/fmt/issues/3738, https://github.com/fmtlib/fmt/issues/3740, https://github.com/fmtlib/fmt/pull/3741, https://github.com/fmtlib/fmt/pull/3743, https://github.com/fmtlib/fmt/issues/3745, https://github.com/fmtlib/fmt/pull/3747, https://github.com/fmtlib/fmt/pull/3748, https://github.com/fmtlib/fmt/pull/3751, https://github.com/fmtlib/fmt/pull/3754, https://github.com/fmtlib/fmt/pull/3755, https://github.com/fmtlib/fmt/issues/3760, https://github.com/fmtlib/fmt/pull/3762, https://github.com/fmtlib/fmt/issues/3763, https://github.com/fmtlib/fmt/pull/3764, https://github.com/fmtlib/fmt/issues/3774). Thanks @danakj, @vinayyadav3016, @cyyever, @phprus, @qimiko, @saschasc, @gsjaardema, @lazka, @Zhaojun-Liu, @carlsmedstad, @hotwatermorning, @cptFracassa, @kuguma, @PeterJohnson, @H1X4Dev, @asantoni, @eltociear, @msimberg, @tchaikov.
-
Improved documentation and README (https://github.com/fmtlib/fmt/issues/2086, https://github.com/fmtlib/fmt/issues/3637, https://github.com/fmtlib/fmt/pull/3642, https://github.com/fmtlib/fmt/pull/3653, https://github.com/fmtlib/fmt/pull/3655, https://github.com/fmtlib/fmt/pull/3661, https://github.com/fmtlib/fmt/issues/3673, https://github.com/fmtlib/fmt/pull/3677, https://github.com/fmtlib/fmt/pull/3737, https://github.com/fmtlib/fmt/issues/3742, https://github.com/fmtlib/fmt/pull/3744). Thanks @idzm, @perlun, @joycebrum, @fennewald, @reinhardt1053, @GeorgeLS.
-
Updated CI dependencies (https://github.com/fmtlib/fmt/pull/3615, https://github.com/fmtlib/fmt/pull/3622, https://github.com/fmtlib/fmt/pull/3623, https://github.com/fmtlib/fmt/pull/3666, https://github.com/fmtlib/fmt/pull/3696, https://github.com/fmtlib/fmt/pull/3697, https://github.com/fmtlib/fmt/pull/3759).
10.1.1 - 2023-08-28
- Added formatters for
std::atomic
andatomic_flag
(https://github.com/fmtlib/fmt/pull/3574, https://github.com/fmtlib/fmt/pull/3594). Thanks @wangzw and @AlexGuteniev. - Fixed an error about partial specialization of
formatter<string>
after instantiation when compiled with gcc and C++20 (https://github.com/fmtlib/fmt/issues/3584). - Fixed compilation as a C++20 module with gcc and clang (https://github.com/fmtlib/fmt/issues/3587, https://github.com/fmtlib/fmt/pull/3597, https://github.com/fmtlib/fmt/pull/3605). Thanks @MathewBensonCode.
- Made
fmt::to_string
work with types that haveformat_as
overloads (https://github.com/fmtlib/fmt/pull/3575). Thanks @phprus. - Made
formatted_size
work with integral format specifiers at compile time (https://github.com/fmtlib/fmt/pull/3591). Thanks @elbeno. - Fixed a warning about the
no_unique_address
attribute on clang-cl (https://github.com/fmtlib/fmt/pull/3599). Thanks @lukester1975. - Improved compatibility with the legacy GBK encoding (https://github.com/fmtlib/fmt/issues/3598, https://github.com/fmtlib/fmt/pull/3599). Thanks @YuHuanTin.
- Added OpenSSF Scorecard analysis (https://github.com/fmtlib/fmt/issues/3530, https://github.com/fmtlib/fmt/pull/3571). Thanks @joycebrum.
- Updated CI dependencies (https://github.com/fmtlib/fmt/pull/3591, https://github.com/fmtlib/fmt/pull/3592, https://github.com/fmtlib/fmt/pull/3593, https://github.com/fmtlib/fmt/pull/3602).
10.1.0 - 2023-08-12
-
Optimized format string compilation resulting in up to 40% speed up in compiled
format_to
and ~4x speed up in compiledformat_to_n
on a concatenation benchmark (https://github.com/fmtlib/fmt/issues/3133, https://github.com/fmtlib/fmt/issues/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
(https://github.com/fmtlib/fmt/pull/3485). Thanks @Minty-Meeo. -
Added formatters for proxy references to elements of
std::vector<bool>
andstd::bitset<N>
(https://github.com/fmtlib/fmt/issues/3567, https://github.com/fmtlib/fmt/pull/3570). For example (godbolt):#include <vector> #include <fmt/std.h> int main() { auto v = std::vector<bool>{true}; fmt::print("{}", v[0]); }
Thanks @phprus and @felix642.
-
Fixed an ambiguous formatter specialization for containers that look like container adaptors such as
boost::flat_set
(https://github.com/fmtlib/fmt/issues/3556, https://github.com/fmtlib/fmt/pull/3561). Thanks @5chmidti. -
Fixed compilation when formatting durations not convertible from
std::chrono::seconds
(https://github.com/fmtlib/fmt/pull/3430). Thanks @patlkli. -
Made the
formatter
specialization forchar*
const-correct (https://github.com/fmtlib/fmt/pull/3432). Thanks @timsong-cpp. -
Made
{}
and{:}
handled consistently during compile-time checks (https://github.com/fmtlib/fmt/issues/3526). -
Disallowed passing temporaries to
make_format_args
to improve API safety by preventing dangling references. -
Improved the compile-time error for unformattable types (https://github.com/fmtlib/fmt/pull/3478). Thanks @BRevzin.
-
Improved the floating-point formatter (https://github.com/fmtlib/fmt/pull/3448, https://github.com/fmtlib/fmt/pull/3450). Thanks @florimond-collette.
-
Fixed handling of precision for
long double
larger than 64 bits. (https://github.com/fmtlib/fmt/issues/3539, https://github.com/fmtlib/fmt/issues/3564). -
Made floating-point and chrono tests less platform-dependent (https://github.com/fmtlib/fmt/issues/3337, https://github.com/fmtlib/fmt/issues/3433, https://github.com/fmtlib/fmt/pull/3434). Thanks @phprus.
-
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 (https://github.com/fmtlib/fmt/pull/3551). Thanks @mjerabek. -
Made
FMT_THROW
assert even if assertions are disabled when compiling with exceptions disabled (https://github.com/fmtlib/fmt/issues/3418, https://github.com/fmtlib/fmt/pull/3439). Thanks @BRevzin. -
Made
format_as
andstd::filesystem::path
formatter work with exotic code unit types. (https://github.com/fmtlib/fmt/pull/3457, https://github.com/fmtlib/fmt/pull/3476). Thanks @gix and @hmbj. -
Added support for the
?
format specifier tostd::filesystem::path
and made the default unescaped for consistency with strings. -
Deprecated the wide stream overload of
printf
. -
Removed unused
basic_printf_parse_context
. -
Improved RTTI detection used when formatting exceptions (https://github.com/fmtlib/fmt/pull/3468). Thanks @danakj.
-
Improved compatibility with VxWorks7 (https://github.com/fmtlib/fmt/pull/3467). Thanks @wenshan1.
-
Improved documentation (https://github.com/fmtlib/fmt/issues/3174, https://github.com/fmtlib/fmt/issues/3423, https://github.com/fmtlib/fmt/pull/3454, https://github.com/fmtlib/fmt/issues/3458, https://github.com/fmtlib/fmt/pull/3461, https://github.com/fmtlib/fmt/issues/3487, https://github.com/fmtlib/fmt/pull/3515). Thanks @zencatalyst, @rlalik and @mikecrowe.
-
Improved build and CI configurations (https://github.com/fmtlib/fmt/issues/3449, https://github.com/fmtlib/fmt/pull/3451, https://github.com/fmtlib/fmt/pull/3452, https://github.com/fmtlib/fmt/pull/3453, https://github.com/fmtlib/fmt/pull/3459, https://github.com/fmtlib/fmt/issues/3481, https://github.com/fmtlib/fmt/pull/3486, https://github.com/fmtlib/fmt/issues/3489, https://github.com/fmtlib/fmt/pull/3496, https://github.com/fmtlib/fmt/issues/3517, https://github.com/fmtlib/fmt/pull/3523, https://github.com/fmtlib/fmt/pull/3563). Thanks @joycebrum, @glebm, @phprus, @petrmanek, @setoye and @abouvier.
-
Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/issues/3408, https://github.com/fmtlib/fmt/issues/3424, https://github.com/fmtlib/fmt/issues/3444, https://github.com/fmtlib/fmt/pull/3446, https://github.com/fmtlib/fmt/pull/3475, https://github.com/fmtlib/fmt/pull/3482, https://github.com/fmtlib/fmt/issues/3492, https://github.com/fmtlib/fmt/pull/3493, https://github.com/fmtlib/fmt/pull/3508, https://github.com/fmtlib/fmt/issues/3509, https://github.com/fmtlib/fmt/issues/3533, https://github.com/fmtlib/fmt/pull/3542, https://github.com/fmtlib/fmt/issues/3543, https://github.com/fmtlib/fmt/issues/3540, https://github.com/fmtlib/fmt/pull/3544, https://github.com/fmtlib/fmt/issues/3548, https://github.com/fmtlib/fmt/pull/3549, https://github.com/fmtlib/fmt/pull/3550, https://github.com/fmtlib/fmt/pull/3552). Thanks @adesitter, @hmbj, @Minty-Meeo, @phprus, @TobiSchluter, @kieranclancy, @alexeedm, @jurihock, @Ozomahtli and @razaqq.
10.0.0 - 2023-05-09
-
Replaced Grisu with a new floating-point formatting algorithm for given precision (https://github.com/fmtlib/fmt/issues/3262, https://github.com/fmtlib/fmt/issues/2750, https://github.com/fmtlib/fmt/pull/3269, https://github.com/fmtlib/fmt/pull/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.
-
Replaced
snprintf
-based hex float formatter with an internal implementation (https://github.com/fmtlib/fmt/pull/3179, https://github.com/fmtlib/fmt/pull/3203). This removes the last usage ofs(n)printf
in {fmt}. Thanks @phprus. -
Fixed alignment of floating-point numbers with localization (https://github.com/fmtlib/fmt/issues/3263, https://github.com/fmtlib/fmt/pull/3272). Thanks @ShawnZhong.
-
Made handling of
#
consistent withstd::format
. -
Improved C++20 module support (https://github.com/fmtlib/fmt/pull/3134, https://github.com/fmtlib/fmt/pull/3254, https://github.com/fmtlib/fmt/pull/3386, https://github.com/fmtlib/fmt/pull/3387, https://github.com/fmtlib/fmt/pull/3388, https://github.com/fmtlib/fmt/pull/3392, https://github.com/fmtlib/fmt/pull/3397, https://github.com/fmtlib/fmt/pull/3399, https://github.com/fmtlib/fmt/pull/3400). Thanks @laitingsheng, @Orvid and @DanielaE.
-
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. Useformat_as
instead. -
Added support for fill, align and width to the time point formatter (https://github.com/fmtlib/fmt/issues/3237, https://github.com/fmtlib/fmt/pull/3260, https://github.com/fmtlib/fmt/pull/3275). For example (godbolt):
#include <fmt/chrono.h> int main() { // prints " 2023" fmt::print("{:>8%Y}\n", std::chrono::system_clock::now()); }
Thanks @ShawnZhong.
-
Implemented formatting of subseconds (https://github.com/fmtlib/fmt/issues/2207, https://github.com/fmtlib/fmt/issues/3117, https://github.com/fmtlib/fmt/pull/3115, https://github.com/fmtlib/fmt/pull/3143, https://github.com/fmtlib/fmt/pull/3144, https://github.com/fmtlib/fmt/pull/3349). For example (godbolt):
#include <fmt/chrono.h> int main() { // prints 01.234567 fmt::print("{:%S}\n", std::chrono::microseconds(1234567)); }
Thanks @patrickroocks @phprus and @BRevzin.
-
Added precision support to
%S
(https://github.com/fmtlib/fmt/pull/3148). Thanks @SappyJoy -
Added support for
std::utc_time
(https://github.com/fmtlib/fmt/issues/3098, https://github.com/fmtlib/fmt/pull/3110). Thanks @patrickroocks. -
Switched formatting of
std::chrono::system_clock
from local time to UTC for compatibility with the standard (https://github.com/fmtlib/fmt/issues/3199, https://github.com/fmtlib/fmt/pull/3230). Thanks @ned14. -
Added support for
%Ez
and%Oz
to chrono formatters. (https://github.com/fmtlib/fmt/issues/3220, https://github.com/fmtlib/fmt/pull/3222). Thanks @phprus. -
Improved validation of format specifiers for
std::chrono::duration
(https://github.com/fmtlib/fmt/issues/3219, https://github.com/fmtlib/fmt/pull/3232). Thanks @ShawnZhong. -
Fixed formatting of time points before the epoch (https://github.com/fmtlib/fmt/issues/3117, https://github.com/fmtlib/fmt/pull/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.
-
Experimental: implemented glibc extension for padding seconds, minutes and hours (https://github.com/fmtlib/fmt/issues/2959, https://github.com/fmtlib/fmt/pull/3271). Thanks @ShawnZhong.
-
Added a formatter for
std::exception
(https://github.com/fmtlib/fmt/issues/2977, https://github.com/fmtlib/fmt/issues/3012, https://github.com/fmtlib/fmt/pull/3062, https://github.com/fmtlib/fmt/pull/3076, https://github.com/fmtlib/fmt/pull/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 and @phprus.
-
Moved
std::error_code
formatter fromfmt/os.h
tofmt/std.h
. (https://github.com/fmtlib/fmt/pull/3125). Thanks @phprus. -
Added formatters for standard container adapters:
std::priority_queue
,std::queue
andstd::stack
(https://github.com/fmtlib/fmt/issues/3215, https://github.com/fmtlib/fmt/pull/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.
-
Added a formatter for
std::optional
tofmt/std.h
(https://github.com/fmtlib/fmt/issues/1367, https://github.com/fmtlib/fmt/pull/3303). Thanks @tom-huntington. -
Fixed formatting of valueless by exception variants (https://github.com/fmtlib/fmt/pull/3347). Thanks @TheOmegaCarrot.
-
Made
fmt::ptr
acceptunique_ptr
with a custom deleter (https://github.com/fmtlib/fmt/pull/3177). Thanks @hmbj. -
Fixed formatting of noncopyable ranges and nested ranges of chars (https://github.com/fmtlib/fmt/pull/3158 https://github.com/fmtlib/fmt/issues/3286, https://github.com/fmtlib/fmt/pull/3290). Thanks @BRevzin.
-
Fixed issues with formatting of paths and ranges of paths (https://github.com/fmtlib/fmt/issues/3319, https://github.com/fmtlib/fmt/pull/3321 https://github.com/fmtlib/fmt/issues/3322). Thanks @phprus.
-
Improved handling of invalid Unicode in paths.
-
Enabled compile-time checks on Apple clang 14 and later (https://github.com/fmtlib/fmt/pull/3331). Thanks @cloyce.
-
Improved compile-time checks of named arguments (https://github.com/fmtlib/fmt/issues/3105, https://github.com/fmtlib/fmt/pull/3214). Thanks @rbrich.
-
Fixed formatting when both alignment and
0
are given (https://github.com/fmtlib/fmt/issues/3236, https://github.com/fmtlib/fmt/pull/3248). Thanks @ShawnZhong. -
Improved Unicode support in the experimental file API on Windows (https://github.com/fmtlib/fmt/issues/3234, https://github.com/fmtlib/fmt/pull/3293). Thanks @Fros1er.
-
Unified UTF transcoding (https://github.com/fmtlib/fmt/pull/3416). Thanks @phprus.
-
Added support for UTF-8 digit separators via an experimental locale facet (https://github.com/fmtlib/fmt/issues/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 (https://github.com/fmtlib/fmt/issues/3084, https://github.com/fmtlib/fmt/pull/3087). Thanks @gerboengels. -
Removed the deprecated
FMT_DEPRECATED_OSTREAM
. -
Fixed a UB when using a null
std::string_view
withfmt::to_string
or format string compilation (https://github.com/fmtlib/fmt/issues/3241, https://github.com/fmtlib/fmt/pull/3244). Thanks @phprus. -
Added
starts_with
to the fallbackstring_view
implementation (https://github.com/fmtlib/fmt/pull/3080). Thanks @phprus. -
Added
fmt::basic_format_string::get()
for compatibility withbasic_format_string
(https://github.com/fmtlib/fmt/pull/3111). Thanks @huangqinjin. -
Added
println
for compatibility with C++23 (https://github.com/fmtlib/fmt/pull/3267). Thanks @ShawnZhong. -
Renamed the
FMT_EXPORT
macro for shared library usage toFMT_LIB_EXPORT
. -
Improved documentation (https://github.com/fmtlib/fmt/issues/3108, https://github.com/fmtlib/fmt/issues/3169, https://github.com/fmtlib/fmt/pull/3243). https://github.com/fmtlib/fmt/pull/3404). Thanks @Cleroth and @Vertexwahn.
-
Improved build configuration and tests (https://github.com/fmtlib/fmt/pull/3118, https://github.com/fmtlib/fmt/pull/3120, https://github.com/fmtlib/fmt/pull/3188, https://github.com/fmtlib/fmt/issues/3189, https://github.com/fmtlib/fmt/pull/3198, https://github.com/fmtlib/fmt/pull/3205, https://github.com/fmtlib/fmt/pull/3207, https://github.com/fmtlib/fmt/pull/3210, https://github.com/fmtlib/fmt/pull/3240, https://github.com/fmtlib/fmt/pull/3256, https://github.com/fmtlib/fmt/pull/3264, https://github.com/fmtlib/fmt/issues/3299, https://github.com/fmtlib/fmt/pull/3302, https://github.com/fmtlib/fmt/pull/3312, https://github.com/fmtlib/fmt/issues/3317, https://github.com/fmtlib/fmt/pull/3328, https://github.com/fmtlib/fmt/pull/3333, https://github.com/fmtlib/fmt/pull/3369, https://github.com/fmtlib/fmt/issues/3373, https://github.com/fmtlib/fmt/pull/3395, https://github.com/fmtlib/fmt/pull/3406, https://github.com/fmtlib/fmt/pull/3411). Thanks @dimztimz, @phprus, @DavidKorczynski, @ChrisThrasher, @FrancoisCarouge, @kennyweiss, @luzpaz, @codeinred, @Mixaill, @joycebrum, @kevinhwang and @Vertexwahn.
-
Fixed a regression in handling empty format specifiers after a colon (
{:}
) (https://github.com/fmtlib/fmt/pull/3086). Thanks @oxidase. -
Worked around a broken implementation of
std::is_constant_evaluated
in some versions of libstdc++ on clang (https://github.com/fmtlib/fmt/issues/3247, https://github.com/fmtlib/fmt/pull/3281). Thanks @phprus. -
Fixed formatting of volatile variables (https://github.com/fmtlib/fmt/pull/3068).
-
Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/pull/3057, https://github.com/fmtlib/fmt/pull/3066, https://github.com/fmtlib/fmt/pull/3072, https://github.com/fmtlib/fmt/pull/3082, https://github.com/fmtlib/fmt/pull/3091, https://github.com/fmtlib/fmt/issues/3092, https://github.com/fmtlib/fmt/pull/3093, https://github.com/fmtlib/fmt/pull/3095, https://github.com/fmtlib/fmt/issues/3096, https://github.com/fmtlib/fmt/pull/3097, https://github.com/fmtlib/fmt/issues/3128, https://github.com/fmtlib/fmt/pull/3129, https://github.com/fmtlib/fmt/pull/3137, https://github.com/fmtlib/fmt/pull/3139, https://github.com/fmtlib/fmt/issues/3140, https://github.com/fmtlib/fmt/pull/3142, https://github.com/fmtlib/fmt/issues/3149, https://github.com/fmtlib/fmt/pull/3150, https://github.com/fmtlib/fmt/issues/3154, https://github.com/fmtlib/fmt/issues/3163, https://github.com/fmtlib/fmt/issues/3178, https://github.com/fmtlib/fmt/pull/3184, https://github.com/fmtlib/fmt/pull/3196, https://github.com/fmtlib/fmt/issues/3204, https://github.com/fmtlib/fmt/pull/3206, https://github.com/fmtlib/fmt/pull/3208, https://github.com/fmtlib/fmt/issues/3213, https://github.com/fmtlib/fmt/pull/3216, https://github.com/fmtlib/fmt/issues/3224, https://github.com/fmtlib/fmt/issues/3226, https://github.com/fmtlib/fmt/issues/3228, https://github.com/fmtlib/fmt/pull/3229, https://github.com/fmtlib/fmt/pull/3259, https://github.com/fmtlib/fmt/issues/3274, https://github.com/fmtlib/fmt/issues/3287, https://github.com/fmtlib/fmt/pull/3288, https://github.com/fmtlib/fmt/issues/3292, https://github.com/fmtlib/fmt/pull/3295, https://github.com/fmtlib/fmt/pull/3296, https://github.com/fmtlib/fmt/issues/3298, https://github.com/fmtlib/fmt/issues/3325, https://github.com/fmtlib/fmt/pull/3326, https://github.com/fmtlib/fmt/issues/3334, https://github.com/fmtlib/fmt/issues/3342, https://github.com/fmtlib/fmt/pull/3343, https://github.com/fmtlib/fmt/issues/3351, https://github.com/fmtlib/fmt/pull/3352, https://github.com/fmtlib/fmt/pull/3362, https://github.com/fmtlib/fmt/issues/3365, https://github.com/fmtlib/fmt/pull/3366, https://github.com/fmtlib/fmt/pull/3374, https://github.com/fmtlib/fmt/issues/3377, https://github.com/fmtlib/fmt/pull/3378, https://github.com/fmtlib/fmt/issues/3381, https://github.com/fmtlib/fmt/pull/3398, https://github.com/fmtlib/fmt/pull/3413, https://github.com/fmtlib/fmt/issues/3415). Thanks @phprus, @gsjaardema, @NewbieOrange, @EngineLessCC, @asmaloney, @HazardyKnusperkeks, @sergiud, @Youw, @thesmurph, @czudziakm, @Roman-Koshelev, @chronoxor, @ShawnZhong, @russelltg, @glebm, @tmartin-gh, @Zhaojun-Liu, @louiswins and @mogemimi.
9.1.0 - 2022-08-27
-
fmt::formatted_size
now works at compile time (https://github.com/fmtlib/fmt/pull/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.
-
Fixed handling of invalid UTF-8 (https://github.com/fmtlib/fmt/pull/3038, https://github.com/fmtlib/fmt/pull/3044, https://github.com/fmtlib/fmt/pull/3056). Thanks @phprus and @skeeto.
-
Improved Unicode support in
ostream
overloads ofprint
(https://github.com/fmtlib/fmt/pull/2994, https://github.com/fmtlib/fmt/pull/3001, https://github.com/fmtlib/fmt/pull/3025). Thanks @dimztimz. -
Fixed handling of the sign specifier in localized formatting on systems with 32-bit
wchar_t
(https://github.com/fmtlib/fmt/issues/3041). -
Added support for wide streams to
fmt::streamed
(https://github.com/fmtlib/fmt/pull/2994). Thanks @phprus. -
Added the
n
specifier that disables the output of delimiters when formatting ranges (https://github.com/fmtlib/fmt/pull/2981, https://github.com/fmtlib/fmt/pull/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.
-
Worked around problematic
std::string_view
constructors introduced in C++23 (https://github.com/fmtlib/fmt/issues/3030, https://github.com/fmtlib/fmt/issues/3050). Thanks @strega-nil-ms. -
Improve handling (exclusion) of recursive ranges (https://github.com/fmtlib/fmt/issues/2968, https://github.com/fmtlib/fmt/pull/2974). Thanks @Dani-Hub.
-
Improved error reporting in format string compilation (https://github.com/fmtlib/fmt/issues/3055).
-
Improved the implementation of Dragonbox, the algorithm used for the default floating-point formatting (https://github.com/fmtlib/fmt/pull/2984). Thanks @jk-jeon.
-
Fixed issues with floating-point formatting on exotic platforms.
-
Improved the implementation of chrono formatting (https://github.com/fmtlib/fmt/pull/3010). Thanks @phprus.
-
Improved documentation (https://github.com/fmtlib/fmt/pull/2966, https://github.com/fmtlib/fmt/pull/3009, https://github.com/fmtlib/fmt/issues/3020, https://github.com/fmtlib/fmt/pull/3037). Thanks @mwinterb, @jcelerier and @remiburtin.
-
Improved build configuration (https://github.com/fmtlib/fmt/pull/2991, https://github.com/fmtlib/fmt/pull/2995, https://github.com/fmtlib/fmt/issues/3004, https://github.com/fmtlib/fmt/pull/3007, https://github.com/fmtlib/fmt/pull/3040). Thanks @dimztimz and @hwhsu1231.
-
Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/issues/2969, https://github.com/fmtlib/fmt/pull/2971, https://github.com/fmtlib/fmt/issues/2975, https://github.com/fmtlib/fmt/pull/2982, https://github.com/fmtlib/fmt/pull/2985, https://github.com/fmtlib/fmt/issues/2988, https://github.com/fmtlib/fmt/issues/2989, https://github.com/fmtlib/fmt/issues/3000, https://github.com/fmtlib/fmt/issues/3006, https://github.com/fmtlib/fmt/issues/3014, https://github.com/fmtlib/fmt/issues/3015, https://github.com/fmtlib/fmt/pull/3021, https://github.com/fmtlib/fmt/issues/3023, https://github.com/fmtlib/fmt/pull/3024, https://github.com/fmtlib/fmt/pull/3029, https://github.com/fmtlib/fmt/pull/3043, https://github.com/fmtlib/fmt/issues/3052, https://github.com/fmtlib/fmt/pull/3053, https://github.com/fmtlib/fmt/pull/3054). Thanks @h-friederich, @dimztimz, @olupton, @bernhardmgruber and @phprus.
9.0.0 - 2022-07-04
-
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 (https://github.com/fmtlib/fmt/pull/2713, https://github.com/fmtlib/fmt/pull/2750). Thanks @jk-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 whenfmt/ostream.h
is included to prevent ODR violations. You can get the old behavior by definingFMT_DEPRECATED_OSTREAM
but this will be removed in the next major release. Usefmt::streamed
orfmt::ostream_formatter
to enable formatting viastd::ostream
instead. -
Added
fmt::ostream_formatter
that can be used to writeformatter
specializations that perform formatting viastd::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 viastd::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 aformatter
specialization forstd::thread::id
so you don't need to format it viastd::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 (https://github.com/fmtlib/fmt/pull/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 (https://github.com/fmtlib/fmt/issues/2865, https://github.com/fmtlib/fmt/pull/2902, https://github.com/fmtlib/fmt/issues/2917, https://github.com/fmtlib/fmt/pull/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.
-
Added a
std::thread::id
formatter tofmt/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 (https://github.com/fmtlib/fmt/pull/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.
-
Made
fmt::print
overload for text styles correctly handle UTF-8 (https://github.com/fmtlib/fmt/issues/2681, https://github.com/fmtlib/fmt/pull/2701). Thanks @AlexGuteniev. -
Fixed Unicode handling when writing to an ostream.
-
Added support for nested specifiers to range formatting (https://github.com/fmtlib/fmt/pull/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.
-
Implemented escaping of wide strings in ranges (https://github.com/fmtlib/fmt/pull/2904). Thanks @phprus.
-
Added support for ranges with
begin
/end
found via the argument-dependent lookup (https://github.com/fmtlib/fmt/pull/2807). Thanks @rbrugo. -
Fixed formatting of certain kinds of ranges of ranges (https://github.com/fmtlib/fmt/pull/2787). Thanks @BRevzin.
-
Fixed handling of maps with element types other than
std::pair
(https://github.com/fmtlib/fmt/pull/2944). Thanks @BrukerJWD. -
Made tuple formatter enabled only if elements are formattable (https://github.com/fmtlib/fmt/issues/2939, https://github.com/fmtlib/fmt/pull/2940). Thanks @jehelset.
-
Made
fmt::join
compatible with format string compilation (https://github.com/fmtlib/fmt/issues/2719, https://github.com/fmtlib/fmt/pull/2720). Thanks @phprus. -
Made compile-time checks work with named arguments of custom types and
std::ostream
print
overloads (https://github.com/fmtlib/fmt/issues/2816, https://github.com/fmtlib/fmt/issues/2817, https://github.com/fmtlib/fmt/pull/2819). Thanks @timsong-cpp. -
Removed
make_args_checked
because it is no longer needed for compile-time checks (https://github.com/fmtlib/fmt/pull/2760). Thanks @phprus. -
Removed the following deprecated APIs:
_format
,arg_join
, theformat_to
overload that takes a memory buffer,[v]fprintf
that takes anostream
. -
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()
withdescriptor()
inbuffered_file
. -
Moved
to_string_view
to thedetail
namespace since it's an implementation detail. -
Made access mode of a created file consistent with
fopen
by settingS_IWGRP
andS_IWOTH
(https://github.com/fmtlib/fmt/pull/2733). Thanks @arogge. -
Removed a redundant buffer resize when formatting to
std::ostream
(https://github.com/fmtlib/fmt/issues/2842, https://github.com/fmtlib/fmt/pull/2843). Thanks @jcelerier. -
Made precision computation for strings consistent with width (https://github.com/fmtlib/fmt/issues/2888).
-
Fixed handling of locale separators in floating point formatting (https://github.com/fmtlib/fmt/issues/2830).
-
Made sign specifiers work with
__int128_t
(https://github.com/fmtlib/fmt/issues/2773). -
Improved support for systems such as CHERI with extra data stored in pointers (https://github.com/fmtlib/fmt/pull/2932). Thanks @davidchisnall.
-
Improved documentation (https://github.com/fmtlib/fmt/pull/2706, https://github.com/fmtlib/fmt/pull/2712, https://github.com/fmtlib/fmt/pull/2789, https://github.com/fmtlib/fmt/pull/2803, https://github.com/fmtlib/fmt/pull/2805, https://github.com/fmtlib/fmt/pull/2815, https://github.com/fmtlib/fmt/pull/2924). Thanks @BRevzin, @Pokechu22, @setoye, @rtobar, @rbrugo, @anoonD and @leha-bot.
-
Improved build configuration (https://github.com/fmtlib/fmt/pull/2766, https://github.com/fmtlib/fmt/pull/2772, https://github.com/fmtlib/fmt/pull/2836, https://github.com/fmtlib/fmt/pull/2852, https://github.com/fmtlib/fmt/pull/2907, https://github.com/fmtlib/fmt/pull/2913, https://github.com/fmtlib/fmt/pull/2914). Thanks @kambala-decapitator, @mattiasljungstrom, @kieselnb, @nathannaveen and @Vertexwahn.
-
Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/issues/2408, https://github.com/fmtlib/fmt/issues/2507, https://github.com/fmtlib/fmt/issues/2697, https://github.com/fmtlib/fmt/issues/2715, https://github.com/fmtlib/fmt/issues/2717, https://github.com/fmtlib/fmt/pull/2722, https://github.com/fmtlib/fmt/pull/2724, https://github.com/fmtlib/fmt/pull/2725, https://github.com/fmtlib/fmt/issues/2726, https://github.com/fmtlib/fmt/pull/2728, https://github.com/fmtlib/fmt/pull/2732, https://github.com/fmtlib/fmt/issues/2738, https://github.com/fmtlib/fmt/pull/2742, https://github.com/fmtlib/fmt/issues/2744, https://github.com/fmtlib/fmt/issues/2745, https://github.com/fmtlib/fmt/issues/2746, https://github.com/fmtlib/fmt/issues/2754, https://github.com/fmtlib/fmt/pull/2755, https://github.com/fmtlib/fmt/issues/2757, https://github.com/fmtlib/fmt/pull/2758, https://github.com/fmtlib/fmt/issues/2761, https://github.com/fmtlib/fmt/pull/2762, https://github.com/fmtlib/fmt/issues/2763, https://github.com/fmtlib/fmt/pull/2765, https://github.com/fmtlib/fmt/issues/2769, https://github.com/fmtlib/fmt/pull/2770, https://github.com/fmtlib/fmt/issues/2771, https://github.com/fmtlib/fmt/issues/2777, https://github.com/fmtlib/fmt/pull/2779, https://github.com/fmtlib/fmt/pull/2782, https://github.com/fmtlib/fmt/pull/2783, https://github.com/fmtlib/fmt/issues/2794, https://github.com/fmtlib/fmt/issues/2796, https://github.com/fmtlib/fmt/pull/2797, https://github.com/fmtlib/fmt/pull/2801, https://github.com/fmtlib/fmt/pull/2802, https://github.com/fmtlib/fmt/issues/2808, https://github.com/fmtlib/fmt/issues/2818, https://github.com/fmtlib/fmt/pull/2819, https://github.com/fmtlib/fmt/issues/2829, https://github.com/fmtlib/fmt/issues/2835, https://github.com/fmtlib/fmt/issues/2848, https://github.com/fmtlib/fmt/issues/2860, https://github.com/fmtlib/fmt/pull/2861, https://github.com/fmtlib/fmt/pull/2882, https://github.com/fmtlib/fmt/issues/2886, https://github.com/fmtlib/fmt/issues/2891, https://github.com/fmtlib/fmt/pull/2892, https://github.com/fmtlib/fmt/issues/2895, https://github.com/fmtlib/fmt/issues/2896, https://github.com/fmtlib/fmt/pull/2903, https://github.com/fmtlib/fmt/issues/2906, https://github.com/fmtlib/fmt/issues/2908, https://github.com/fmtlib/fmt/pull/2909, https://github.com/fmtlib/fmt/issues/2920, https://github.com/fmtlib/fmt/pull/2922, https://github.com/fmtlib/fmt/pull/2927, https://github.com/fmtlib/fmt/pull/2929, https://github.com/fmtlib/fmt/issues/2936, https://github.com/fmtlib/fmt/pull/2937, https://github.com/fmtlib/fmt/pull/2938, https://github.com/fmtlib/fmt/pull/2951, https://github.com/fmtlib/fmt/issues/2954, https://github.com/fmtlib/fmt/pull/2957, https://github.com/fmtlib/fmt/issues/2958, https://github.com/fmtlib/fmt/pull/2960). Thanks @matrackif @Tobi823, @ivan-volnov, @VasiliPupkin256, @federico-busato, @barcharcraz, @jk-jeon, @HazardyKnusperkeks, @dalboris, @seanm, @gsjaardema, @timsong-cpp, @seanm, @frithrah, @chronoxor, @Agga, @madmaxoft, @JurajX, @phprus and @Dani-Hub.
8.1.1 - 2022-01-06
- Restored ABI compatibility with version 8.0.x (https://github.com/fmtlib/fmt/issues/2695, https://github.com/fmtlib/fmt/pull/2696). Thanks @saraedum.
- Fixed chrono formatting on big endian systems (https://github.com/fmtlib/fmt/issues/2698, https://github.com/fmtlib/fmt/pull/2699). Thanks @phprus and @xvitaly.
- Fixed a linkage error with mingw (https://github.com/fmtlib/fmt/issues/2691, https://github.com/fmtlib/fmt/pull/2692). Thanks @rbberger.
8.1.0 - 2022-01-02
-
Optimized chrono formatting (https://github.com/fmtlib/fmt/pull/2500, https://github.com/fmtlib/fmt/pull/2537, https://github.com/fmtlib/fmt/issues/2541, https://github.com/fmtlib/fmt/pull/2544, https://github.com/fmtlib/fmt/pull/2550, https://github.com/fmtlib/fmt/pull/2551, https://github.com/fmtlib/fmt/pull/2576, https://github.com/fmtlib/fmt/issues/2577, https://github.com/fmtlib/fmt/pull/2586, https://github.com/fmtlib/fmt/pull/2591, https://github.com/fmtlib/fmt/pull/2594, https://github.com/fmtlib/fmt/pull/2602, https://github.com/fmtlib/fmt/pull/2617, https://github.com/fmtlib/fmt/issues/2628, https://github.com/fmtlib/fmt/pull/2633, https://github.com/fmtlib/fmt/issues/2670, https://github.com/fmtlib/fmt/pull/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 and @toughengineer.
-
Implemented subsecond formatting for chrono durations (https://github.com/fmtlib/fmt/pull/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 (https://github.com/fmtlib/fmt/issues/2587, https://github.com/fmtlib/fmt/pull/2588). Thanks @lukester1975.
-
Fixed an overflow on invalid inputs in the
tm
formatter (https://github.com/fmtlib/fmt/pull/2564). Thanks @phprus. -
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 (https://github.com/fmtlib/fmt/pull/2394):
https://user-images.githubusercontent.com/576385/147710227-c68f5317-f8fa-42c3-9123-7c4ba3c398cb.mp4
Thanks @benit8 and @data-man.
-
Added experimental support for compile-time floating point formatting (https://github.com/fmtlib/fmt/pull/2426, https://github.com/fmtlib/fmt/pull/2470). It is currently limited to the header-only mode. Thanks @alexezeder.
-
Added UDL-based named argument support to compile-time format string checks (https://github.com/fmtlib/fmt/issues/2640, https://github.com/fmtlib/fmt/pull/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+) becauses
is not a valid format specifier for an integer.Thanks @alexezeder.
-
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"]
-
Added an experimental
?
specifier for escaping strings. (https://github.com/fmtlib/fmt/pull/2674). Thanks @BRevzin. -
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 (https://github.com/fmtlib/fmt/pull/2549). Thanks @BRevzin. -
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 (https://github.com/fmtlib/fmt/pull/1841).
-
Deprecated implicit conversion of
[const] signed char*
and[const] unsigned char*
to C strings. -
Deprecated
_format
, a legacy UDL-based format API (https://github.com/fmtlib/fmt/pull/2646). Thanks @alexezeder. -
Marked
format
,formatted_size
andto_string
as[[nodiscard]]
(https://github.com/fmtlib/fmt/pull/2612). @0x8000-0000. -
Added missing diagnostic when trying to format function and member pointers as well as objects convertible to pointers which is explicitly disallowed (https://github.com/fmtlib/fmt/issues/2598, https://github.com/fmtlib/fmt/pull/2609, https://github.com/fmtlib/fmt/pull/2610). Thanks @AlexGuteniev.
-
Optimized writing to a contiguous buffer with
format_to_n
(https://github.com/fmtlib/fmt/pull/2489). Thanks @Roman-Koshelev. -
Optimized writing to non-
char
buffers (https://github.com/fmtlib/fmt/pull/2477). Thanks @Roman-Koshelev. -
Decimal point is now localized when using the
L
specifier. -
Improved floating point formatter implementation (https://github.com/fmtlib/fmt/pull/2498, https://github.com/fmtlib/fmt/pull/2499). Thanks @Roman-Koshelev.
-
Fixed handling of very large precision in fixed format (https://github.com/fmtlib/fmt/pull/2616).
-
Made a table of cached powers used in FP formatting static (https://github.com/fmtlib/fmt/pull/2509). Thanks @jk-jeon.
-
Resolved a lookup ambiguity with C++20 format-related functions due to ADL (https://github.com/fmtlib/fmt/issues/2639, https://github.com/fmtlib/fmt/pull/2641). Thanks @mkurdej.
-
Removed unnecessary inline namespace qualification (https://github.com/fmtlib/fmt/issues/2642, https://github.com/fmtlib/fmt/pull/2643). Thanks @mkurdej.
-
Implemented argument forwarding in
format_to_n
(https://github.com/fmtlib/fmt/issues/2462, https://github.com/fmtlib/fmt/pull/2463). Thanks @owent. -
Fixed handling of implicit conversions in
fmt::to_string
and format string compilation (https://github.com/fmtlib/fmt/issues/2565). -
Changed the default access mode of files created by
fmt::output_file
to-rw-r--r--
for consistency withfopen
(https://github.com/fmtlib/fmt/issues/2530). -
Make
fmt::ostream::flush
public (https://github.com/fmtlib/fmt/issues/2435). -
Improved C++14/17 attribute detection (https://github.com/fmtlib/fmt/pull/2615). Thanks @AlexGuteniev.
-
Improved
consteval
detection for MSVC (https://github.com/fmtlib/fmt/pull/2559). Thanks @DanielaE. -
Improved documentation (https://github.com/fmtlib/fmt/issues/2406, https://github.com/fmtlib/fmt/pull/2446, https://github.com/fmtlib/fmt/issues/2493, https://github.com/fmtlib/fmt/issues/2513, https://github.com/fmtlib/fmt/pull/2515, https://github.com/fmtlib/fmt/issues/2522, https://github.com/fmtlib/fmt/pull/2562, https://github.com/fmtlib/fmt/pull/2575, https://github.com/fmtlib/fmt/pull/2606, https://github.com/fmtlib/fmt/pull/2620, https://github.com/fmtlib/fmt/issues/2676). Thanks @sobolevn, @UnePierre, @zhsj, @phprus, @ericcurtin and @Lounarok.
-
Improved fuzzers and added a fuzzer for chrono timepoint formatting (https://github.com/fmtlib/fmt/pull/2461, https://github.com/fmtlib/fmt/pull/2469). @pauldreik,
-
Added the
FMT_SYSTEM_HEADERS
CMake option setting which marks {fmt}'s headers as system. It can be used to suppress warnings (https://github.com/fmtlib/fmt/issues/2644, https://github.com/fmtlib/fmt/pull/2651). Thanks @alexezeder. -
Added the Bazel build system support (https://github.com/fmtlib/fmt/pull/2505, https://github.com/fmtlib/fmt/pull/2516). Thanks @Vertexwahn.
-
Improved build configuration and tests (https://github.com/fmtlib/fmt/issues/2437, https://github.com/fmtlib/fmt/pull/2558, https://github.com/fmtlib/fmt/pull/2648, https://github.com/fmtlib/fmt/pull/2650, https://github.com/fmtlib/fmt/pull/2663, https://github.com/fmtlib/fmt/pull/2677). Thanks @DanielaE, @alexezeder and @phprus.
-
Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/pull/2353, https://github.com/fmtlib/fmt/pull/2356, https://github.com/fmtlib/fmt/pull/2399, https://github.com/fmtlib/fmt/issues/2408, https://github.com/fmtlib/fmt/pull/2414, https://github.com/fmtlib/fmt/pull/2427, https://github.com/fmtlib/fmt/pull/2432, https://github.com/fmtlib/fmt/pull/2442, https://github.com/fmtlib/fmt/pull/2434, https://github.com/fmtlib/fmt/issues/2439, https://github.com/fmtlib/fmt/pull/2447, https://github.com/fmtlib/fmt/pull/2450, https://github.com/fmtlib/fmt/issues/2455, https://github.com/fmtlib/fmt/issues/2465, https://github.com/fmtlib/fmt/issues/2472, https://github.com/fmtlib/fmt/issues/2474, https://github.com/fmtlib/fmt/pull/2476, https://github.com/fmtlib/fmt/issues/2478, https://github.com/fmtlib/fmt/issues/2479, https://github.com/fmtlib/fmt/issues/2481, https://github.com/fmtlib/fmt/pull/2482, https://github.com/fmtlib/fmt/pull/2483, https://github.com/fmtlib/fmt/issues/2490, https://github.com/fmtlib/fmt/pull/2491, https://github.com/fmtlib/fmt/pull/2510, https://github.com/fmtlib/fmt/pull/2518, https://github.com/fmtlib/fmt/issues/2528, https://github.com/fmtlib/fmt/pull/2529, https://github.com/fmtlib/fmt/pull/2539, https://github.com/fmtlib/fmt/issues/2540, https://github.com/fmtlib/fmt/pull/2545, https://github.com/fmtlib/fmt/pull/2555, https://github.com/fmtlib/fmt/issues/2557, https://github.com/fmtlib/fmt/issues/2570, https://github.com/fmtlib/fmt/pull/2573, https://github.com/fmtlib/fmt/pull/2582, https://github.com/fmtlib/fmt/issues/2605, https://github.com/fmtlib/fmt/pull/2611, https://github.com/fmtlib/fmt/pull/2647, https://github.com/fmtlib/fmt/issues/2627, https://github.com/fmtlib/fmt/pull/2630, https://github.com/fmtlib/fmt/issues/2635, https://github.com/fmtlib/fmt/issues/2638, https://github.com/fmtlib/fmt/issues/2653, https://github.com/fmtlib/fmt/issues/2654, https://github.com/fmtlib/fmt/issues/2661, https://github.com/fmtlib/fmt/pull/2664, https://github.com/fmtlib/fmt/pull/2684). Thanks @DanielaE, @mwinterb, @cdacamar, @TrebledJ, @bodomartin, @cquammen, @white238, @mmarkeloff, @palacaze, @jcelerier, @mborn-adi, @BrukerJWD, @spyridon97, @phprus, @oliverlee, @joshessman-llnl, @akohlmey, @timkalu, @olupton, @Acretock, @alexezeder, @andrewcorrigan, @lucpelletier and @HazardyKnusperkeks.
8.0.1 - 2021-07-02
- Fixed the version number in the inline namespace (https://github.com/fmtlib/fmt/issues/2374).
- Added a missing presentation type check for
std::string
(https://github.com/fmtlib/fmt/issues/2402). - Fixed a linkage error when mixing code built with clang and gcc (https://github.com/fmtlib/fmt/issues/2377).
- Fixed documentation issues (https://github.com/fmtlib/fmt/pull/2396, https://github.com/fmtlib/fmt/issues/2403, https://github.com/fmtlib/fmt/issues/2406). Thanks @mkurdej.
- Removed dead code in FP formatter ( https://github.com/fmtlib/fmt/pull/2398). Thanks @javierhonduco.
- Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/issues/2351, https://github.com/fmtlib/fmt/issues/2359, https://github.com/fmtlib/fmt/pull/2365, https://github.com/fmtlib/fmt/issues/2368, https://github.com/fmtlib/fmt/pull/2370, https://github.com/fmtlib/fmt/pull/2376, https://github.com/fmtlib/fmt/pull/2381, https://github.com/fmtlib/fmt/pull/2382, https://github.com/fmtlib/fmt/issues/2386, https://github.com/fmtlib/fmt/pull/2389, https://github.com/fmtlib/fmt/pull/2395, https://github.com/fmtlib/fmt/pull/2397, https://github.com/fmtlib/fmt/issues/2400, https://github.com/fmtlib/fmt/issues/2401, https://github.com/fmtlib/fmt/pull/2407). Thanks @zx2c4, @AidanSun05, @mattiasljungstrom, @joemmett, @erengy, @patlkli, @gsjaardema and @phprus.
8.0.0 - 2021-06-21
-
Enabled compile-time format string checks by default. For example (godbolt):
#include <fmt/core.h> int main() { fmt::print("{:d}", "I am not a number"); }
gives a compile-time error on compilers with C++20
consteval
support (gcc 10+, clang 11+) becaused
is not a valid format specifier for a string.To pass a runtime string wrap it in
fmt::runtime
:fmt::print(fmt::runtime("{:d}"), "I am not a number");
-
Added compile-time formatting (https://github.com/fmtlib/fmt/pull/2019, https://github.com/fmtlib/fmt/pull/2044, https://github.com/fmtlib/fmt/pull/2056, https://github.com/fmtlib/fmt/pull/2072, https://github.com/fmtlib/fmt/pull/2075, https://github.com/fmtlib/fmt/issues/2078, https://github.com/fmtlib/fmt/pull/2129, https://github.com/fmtlib/fmt/pull/2326). For example (godbolt):
#include <fmt/compile.h> consteval auto compile_time_itoa(int 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_itoa(42);
Most of the formatting functionality is available at compile time with a notable exception of floating-point numbers and pointers. Thanks @alexezeder.
-
Optimized handling of format specifiers during format string compilation. For example, hexadecimal formatting (
"{:x}"
) is now 3-7x faster than before when usingformat_to
with format string compilation and a stack-allocated buffer (https://github.com/fmtlib/fmt/issues/1944).Before (7.1.3):
---------------------------------------------------------------------------- Benchmark Time CPU Iterations ---------------------------------------------------------------------------- FMTCompileOld/0 15.5 ns 15.5 ns 43302898 FMTCompileOld/42 16.6 ns 16.6 ns 43278267 FMTCompileOld/273123 18.7 ns 18.6 ns 37035861 FMTCompileOld/9223372036854775807 19.4 ns 19.4 ns 35243000 ----------------------------------------------------------------------------
After (8.x):
---------------------------------------------------------------------------- Benchmark Time CPU Iterations ---------------------------------------------------------------------------- FMTCompileNew/0 1.99 ns 1.99 ns 360523686 FMTCompileNew/42 2.33 ns 2.33 ns 279865664 FMTCompileNew/273123 3.72 ns 3.71 ns 190230315 FMTCompileNew/9223372036854775807 5.28 ns 5.26 ns 130711631 ----------------------------------------------------------------------------
It is even faster than
std::to_chars
from libc++ compiled with clang on macOS:---------------------------------------------------------------------------- Benchmark Time CPU Iterations ---------------------------------------------------------------------------- ToChars/0 4.42 ns 4.41 ns 160196630 ToChars/42 5.00 ns 4.98 ns 140735201 ToChars/273123 7.26 ns 7.24 ns 95784130 ToChars/9223372036854775807 8.77 ns 8.75 ns 75872534 ----------------------------------------------------------------------------
In other cases, especially involving
std::string
construction, the speed up is usually lower because handling format specifiers takes a smaller fraction of the total time. -
Added the
_cf
user-defined literal to represent a compiled format string. It can be used instead of theFMT_COMPILE
macro (https://github.com/fmtlib/fmt/pull/2043, https://github.com/fmtlib/fmt/pull/2242):#include <fmt/compile.h> using namespace fmt::literals; auto s = fmt::format(FMT_COMPILE("{}"), 42); // 🙁 not modern auto s = fmt::format("{}"_cf, 42); // 🙂 modern as hell
It requires compiler support for class types in non-type template parameters (a C++20 feature) which is available in GCC 9.3+. Thanks @alexezeder.
-
Format string compilation now requires
format
functions offormatter
specializations for user-defined types to beconst
:template <> struct fmt::formatter<my_type>: formatter<string_view> { template <typename FormatContext> auto format(my_type obj, FormatContext& ctx) const { // Note const here. // ... } };
-
Added UDL-based named argument support to format string compilation (https://github.com/fmtlib/fmt/pull/2243, https://github.com/fmtlib/fmt/pull/2281). For example:
#include <fmt/compile.h> using namespace fmt::literals; auto s = fmt::format(FMT_COMPILE("{answer}"), "answer"_a = 42);
Here the argument named "answer" is resolved at compile time with no runtime overhead. Thanks @alexezeder.
-
Added format string compilation support to
fmt::print
(https://github.com/fmtlib/fmt/issues/2280, https://github.com/fmtlib/fmt/pull/2304). Thanks @alexezeder. -
Added initial support for compiling {fmt} as a C++20 module (https://github.com/fmtlib/fmt/pull/2235, https://github.com/fmtlib/fmt/pull/2240, https://github.com/fmtlib/fmt/pull/2260, https://github.com/fmtlib/fmt/pull/2282, https://github.com/fmtlib/fmt/pull/2283, https://github.com/fmtlib/fmt/pull/2288, https://github.com/fmtlib/fmt/pull/2298, https://github.com/fmtlib/fmt/pull/2306, https://github.com/fmtlib/fmt/pull/2307, https://github.com/fmtlib/fmt/pull/2309, https://github.com/fmtlib/fmt/pull/2318, https://github.com/fmtlib/fmt/pull/2324, https://github.com/fmtlib/fmt/pull/2332, https://github.com/fmtlib/fmt/pull/2340). Thanks @DanielaE.
-
Made symbols private by default reducing shared library size (https://github.com/fmtlib/fmt/pull/2301). For example there was a ~15% reported reduction on one platform. Thanks @sergiud.
-
Optimized includes making the result of preprocessing
fmt/format.h
~20% smaller with libstdc++/C++20 and slightly improving build times (https://github.com/fmtlib/fmt/issues/1998). -
Added support of ranges with non-const
begin
/end
(https://github.com/fmtlib/fmt/pull/1953). Thanks @kitegi. -
Added support of
std::byte
and other formattable types tofmt::join
(https://github.com/fmtlib/fmt/issues/1981, https://github.com/fmtlib/fmt/issues/2040, https://github.com/fmtlib/fmt/pull/2050, https://github.com/fmtlib/fmt/issues/2262). For example:#include <fmt/format.h> #include <cstddef> #include <vector> int main() { auto bytes = std::vector{std::byte(4), std::byte(2)}; fmt::print("{}", fmt::join(bytes, "")); }
prints "42".
Thanks @kamibo.
-
Implemented the default format for
std::chrono::system_clock
(https://github.com/fmtlib/fmt/issues/2319, https://github.com/fmtlib/fmt/pull/2345). For example:#include <fmt/chrono.h> int main() { fmt::print("{}", std::chrono::system_clock::now()); }
prints "2021-06-18 15:22:00" (the output depends on the current date and time). Thanks @sunmy2019.
-
Made more chrono specifiers locale independent by default. Use the
'L'
specifier to get localized formatting. For example:#include <fmt/chrono.h> int main() { std::locale::global(std::locale("ru_RU.UTF-8")); auto monday = std::chrono::weekday(1); fmt::print("{}\n", monday); // prints "Mon" fmt::print("{:L}\n", monday); // prints "пн" }
-
Improved locale handling in chrono formatting (https://github.com/fmtlib/fmt/issues/2337, https://github.com/fmtlib/fmt/pull/2349, https://github.com/fmtlib/fmt/pull/2350). Thanks @phprus.
-
Deprecated
fmt/locale.h
moving the formatting functions that take a locale tofmt/format.h
(char
) andfmt/xchar
(other overloads). This doesn't introduce a dependency on<locale>
so there is virtually no compile time effect. -
Deprecated an undocumented
format_to
overload that takesbasic_memory_buffer
. -
Made parameter order in
vformat_to
consistent withformat_to
(https://github.com/fmtlib/fmt/issues/2327). -
Added support for time points with arbitrary durations (https://github.com/fmtlib/fmt/issues/2208). For example:
#include <fmt/chrono.h> int main() { using tp = std::chrono::time_point< std::chrono::system_clock, std::chrono::seconds>; fmt::print("{:%S}", tp(std::chrono::seconds(42))); }
prints "42".
-
Formatting floating-point numbers no longer produces trailing zeros by default for consistency with
std::format
. For example:#include <fmt/core.h> int main() { fmt::print("{0:.3}", 1.1); }
prints "1.1". Use the
'#'
specifier to keep trailing zeros. -
Dropped a limit on the number of elements in a range and replaced
{}
with[]
as range delimiters for consistency with Python'sstr.format
. -
The
'L'
specifier for locale-specific numeric formatting can now be combined with presentation specifiers as instd::format
. For example:#include <fmt/core.h> #include <locale> int main() { std::locale::global(std::locale("fr_FR.UTF-8")); fmt::print("{0:.2Lf}", 0.42); }
prints "0,42". The deprecated
'n'
specifier has been removed. -
Made the
0
specifier ignored for infinity and NaN (https://github.com/fmtlib/fmt/issues/2305, https://github.com/fmtlib/fmt/pull/2310). Thanks @Liedtke. -
Made the hexfloat formatting use the right alignment by default (https://github.com/fmtlib/fmt/issues/2308, https://github.com/fmtlib/fmt/pull/2317). Thanks @Liedtke.
-
Removed the deprecated numeric alignment (
'='
). Use the'0'
specifier instead. -
Removed the deprecated
fmt/posix.h
header that has been replaced withfmt/os.h
. -
Removed the deprecated
format_to_n_context
,format_to_n_args
andmake_format_to_n_args
. They have been replaced withformat_context
,format_args` and
make_format_args`` respectively. -
Moved
wchar_t
-specific functions and types tofmt/xchar.h
. You can defineFMT_DEPRECATED_INCLUDE_XCHAR
to automatically includefmt/xchar.h
fromfmt/format.h
but this will be disabled in the next major release. -
Fixed handling of the
'+'
specifier in localized formatting (https://github.com/fmtlib/fmt/issues/2133). -
Added support for the
's'
format specifier that gives textual representation ofbool
(https://github.com/fmtlib/fmt/issues/2094, https://github.com/fmtlib/fmt/pull/2109). For example:#include <fmt/core.h> int main() { fmt::print("{:s}", true); }
prints "true". Thanks @powercoderlol.
-
Made
fmt::ptr
work with function pointers (https://github.com/fmtlib/fmt/pull/2131). For example:#include <fmt/format.h> int main() { fmt::print("My main: {}\n", fmt::ptr(main)); }
Thanks @mikecrowe.
-
The undocumented support for specializing
formatter
for pointer types has been removed. -
Fixed
fmt::formatted_size
with format string compilation (https://github.com/fmtlib/fmt/pull/2141, https://github.com/fmtlib/fmt/pull/2161). Thanks @alexezeder. -
Fixed handling of empty format strings during format string compilation (https://github.com/fmtlib/fmt/issues/2042):
auto s = fmt::format(FMT_COMPILE(""));
Thanks @alexezeder.
-
Fixed handling of enums in
fmt::to_string
(https://github.com/fmtlib/fmt/issues/2036). -
Improved width computation (https://github.com/fmtlib/fmt/issues/2033, https://github.com/fmtlib/fmt/issues/2091). For example:
#include <fmt/core.h> int main() { fmt::print("{:-<10}{}\n", "你好", "世界"); fmt::print("{:-<10}{}\n", "hello", "world"); }
prints
on a modern terminal.
-
The experimental fast output stream (
fmt::ostream
) is now truncated by default for consistency withfopen
(https://github.com/fmtlib/fmt/issues/2018). For example:#include <fmt/os.h> int main() { fmt::ostream out1 = fmt::output_file("guide"); out1.print("Zaphod"); out1.close(); fmt::ostream out2 = fmt::output_file("guide"); out2.print("Ford"); }
writes "Ford" to the file "guide". To preserve the old file content if any pass
fmt::file::WRONLY | fmt::file::CREATE
flags tofmt::output_file
. -
Fixed moving of
fmt::ostream
that holds buffered data (https://github.com/fmtlib/fmt/issues/2197, https://github.com/fmtlib/fmt/pull/2198). Thanks @vtta. -
Replaced the
fmt::system_error
exception with a function of the same name that constructsstd::system_error
(https://github.com/fmtlib/fmt/issues/2266). -
Replaced the
fmt::windows_error
exception with a function of the same name that constructsstd::system_error
with the category returned byfmt::system_category()
(https://github.com/fmtlib/fmt/issues/2274, https://github.com/fmtlib/fmt/pull/2275). The latter is similar tostd::sytem_category
but correctly handles UTF-8. Thanks @phprus. -
Replaced
fmt::error_code
withstd::error_code
and made it formattable (https://github.com/fmtlib/fmt/issues/2269, https://github.com/fmtlib/fmt/pull/2270, https://github.com/fmtlib/fmt/pull/2273). Thanks @phprus. -
Added speech synthesis support (https://github.com/fmtlib/fmt/pull/2206).
-
Made
format_to
work with a memory buffer that has a custom allocator (https://github.com/fmtlib/fmt/pull/2300). Thanks @voxmea. -
Added
Allocator::max_size
support tobasic_memory_buffer
. (https://github.com/fmtlib/fmt/pull/1960). Thanks @phprus. -
Added wide string support to
fmt::join
(https://github.com/fmtlib/fmt/pull/2236). Thanks @crbrz. -
Made iterators passed to
formatter
specializations via a format context satisfy C++20std::output_iterator
requirements (https://github.com/fmtlib/fmt/issues/2156, https://github.com/fmtlib/fmt/pull/2158, https://github.com/fmtlib/fmt/issues/2195, https://github.com/fmtlib/fmt/pull/2204). Thanks @randomnetcat. -
Optimized the
printf
implementation (https://github.com/fmtlib/fmt/pull/1982, https://github.com/fmtlib/fmt/pull/1984, https://github.com/fmtlib/fmt/pull/2016, https://github.com/fmtlib/fmt/pull/2164). Thanks @rimathia and @moiwi. -
Improved detection of
constexpr
char_traits
(https://github.com/fmtlib/fmt/pull/2246, https://github.com/fmtlib/fmt/pull/2257). Thanks @phprus. -
Fixed writing to
stdout
when it is redirected toNUL
on Windows (https://github.com/fmtlib/fmt/issues/2080). -
Fixed exception propagation from iterators (https://github.com/fmtlib/fmt/issues/2097).
-
Improved
strftime
error handling (https://github.com/fmtlib/fmt/issues/2238, https://github.com/fmtlib/fmt/pull/2244). Thanks @yumeyao. -
Stopped using deprecated GCC UDL template extension.
-
Added
fmt/args.h
to the install target (https://github.com/fmtlib/fmt/issues/2096). -
Error messages are now passed to assert when exceptions are disabled (https://github.com/fmtlib/fmt/pull/2145). Thanks @NobodyXu.
-
Added the
FMT_MASTER_PROJECT
CMake option to control build and install targets when {fmt} is included viaadd_subdirectory
(https://github.com/fmtlib/fmt/issues/2098, https://github.com/fmtlib/fmt/pull/2100). Thanks @randomizedthinking. -
Improved build configuration (https://github.com/fmtlib/fmt/pull/2026, https://github.com/fmtlib/fmt/pull/2122). Thanks @luncliff and @ibaned.
-
Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/issues/1947, https://github.com/fmtlib/fmt/pull/1959, https://github.com/fmtlib/fmt/pull/1963, https://github.com/fmtlib/fmt/pull/1965, https://github.com/fmtlib/fmt/issues/1966, https://github.com/fmtlib/fmt/pull/1974, https://github.com/fmtlib/fmt/pull/1975, https://github.com/fmtlib/fmt/pull/1990, https://github.com/fmtlib/fmt/issues/2000, https://github.com/fmtlib/fmt/pull/2001, https://github.com/fmtlib/fmt/issues/2002, https://github.com/fmtlib/fmt/issues/2004, https://github.com/fmtlib/fmt/pull/2006, https://github.com/fmtlib/fmt/pull/2009, https://github.com/fmtlib/fmt/pull/2010, https://github.com/fmtlib/fmt/issues/2038, https://github.com/fmtlib/fmt/issues/2039, https://github.com/fmtlib/fmt/issues/2047, https://github.com/fmtlib/fmt/pull/2053, https://github.com/fmtlib/fmt/issues/2059, https://github.com/fmtlib/fmt/pull/2065, https://github.com/fmtlib/fmt/pull/2067, https://github.com/fmtlib/fmt/pull/2068, https://github.com/fmtlib/fmt/pull/2073, https://github.com/fmtlib/fmt/issues/2103, https://github.com/fmtlib/fmt/issues/2105, https://github.com/fmtlib/fmt/pull/2106, https://github.com/fmtlib/fmt/pull/2107, https://github.com/fmtlib/fmt/issues/2116, https://github.com/fmtlib/fmt/pull/2117, https://github.com/fmtlib/fmt/issues/2118, https://github.com/fmtlib/fmt/pull/2119, https://github.com/fmtlib/fmt/issues/2127, https://github.com/fmtlib/fmt/pull/2128, https://github.com/fmtlib/fmt/issues/2140, https://github.com/fmtlib/fmt/issues/2142, https://github.com/fmtlib/fmt/pull/2143, https://github.com/fmtlib/fmt/pull/2144, https://github.com/fmtlib/fmt/issues/2147, https://github.com/fmtlib/fmt/issues/2148, https://github.com/fmtlib/fmt/issues/2149, https://github.com/fmtlib/fmt/pull/2152, https://github.com/fmtlib/fmt/pull/2160, https://github.com/fmtlib/fmt/issues/2170, https://github.com/fmtlib/fmt/issues/2175, https://github.com/fmtlib/fmt/issues/2176, https://github.com/fmtlib/fmt/pull/2177, https://github.com/fmtlib/fmt/issues/2178, https://github.com/fmtlib/fmt/pull/2179, https://github.com/fmtlib/fmt/issues/2180, https://github.com/fmtlib/fmt/issues/2181, https://github.com/fmtlib/fmt/pull/2183, https://github.com/fmtlib/fmt/issues/2184, https://github.com/fmtlib/fmt/issues/2185, https://github.com/fmtlib/fmt/pull/2186, https://github.com/fmtlib/fmt/pull/2187, https://github.com/fmtlib/fmt/pull/2190, https://github.com/fmtlib/fmt/pull/2192, https://github.com/fmtlib/fmt/pull/2194, https://github.com/fmtlib/fmt/pull/2205, https://github.com/fmtlib/fmt/issues/2210, https://github.com/fmtlib/fmt/pull/2211, https://github.com/fmtlib/fmt/pull/2215, https://github.com/fmtlib/fmt/pull/2216, https://github.com/fmtlib/fmt/pull/2218, https://github.com/fmtlib/fmt/pull/2220, https://github.com/fmtlib/fmt/issues/2228, https://github.com/fmtlib/fmt/pull/2229, https://github.com/fmtlib/fmt/pull/2230, https://github.com/fmtlib/fmt/issues/2233, https://github.com/fmtlib/fmt/pull/2239, https://github.com/fmtlib/fmt/issues/2248, https://github.com/fmtlib/fmt/issues/2252, https://github.com/fmtlib/fmt/pull/2253, https://github.com/fmtlib/fmt/pull/2255, https://github.com/fmtlib/fmt/issues/2261, https://github.com/fmtlib/fmt/issues/2278, https://github.com/fmtlib/fmt/issues/2284, https://github.com/fmtlib/fmt/pull/2287, https://github.com/fmtlib/fmt/pull/2289, https://github.com/fmtlib/fmt/pull/2290, https://github.com/fmtlib/fmt/pull/2293, https://github.com/fmtlib/fmt/issues/2295, https://github.com/fmtlib/fmt/pull/2296, https://github.com/fmtlib/fmt/pull/2297, https://github.com/fmtlib/fmt/issues/2311, https://github.com/fmtlib/fmt/pull/2313, https://github.com/fmtlib/fmt/pull/2315, https://github.com/fmtlib/fmt/issues/2320, https://github.com/fmtlib/fmt/pull/2321, https://github.com/fmtlib/fmt/pull/2323, https://github.com/fmtlib/fmt/issues/2328, https://github.com/fmtlib/fmt/pull/2329, https://github.com/fmtlib/fmt/pull/2333, https://github.com/fmtlib/fmt/pull/2338, https://github.com/fmtlib/fmt/pull/2341). Thanks @darklukee, @fagg, @killerbot242, @jgopel, @yeswalrus, @Finkman, @HazardyKnusperkeks, @dkavolis, @concatime, @chronoxor, @summivox, @yNeo, @Apache-HB, @alexezeder, @toojays, @Brainy0207, @vadz, @imsherlock, @phprus, @white238, @yafshar, @BillyDonahue, @jstaahl, @denchat, @DanielaE, @ilyakurdyukov, @ilmai, @JessyDL, @sergiud, @mwinterb, @sven-herrmann, @jmelas, @twoixter, @crbrz and @upsj.
-
Improved documentation (https://github.com/fmtlib/fmt/issues/1986, https://github.com/fmtlib/fmt/pull/2051, https://github.com/fmtlib/fmt/issues/2057, https://github.com/fmtlib/fmt/pull/2081, https://github.com/fmtlib/fmt/issues/2084, https://github.com/fmtlib/fmt/pull/2312). Thanks @imba-tjd, @0x416c69 and @mordante.
-
Continuous integration and test improvements (https://github.com/fmtlib/fmt/issues/1969, https://github.com/fmtlib/fmt/pull/1991, https://github.com/fmtlib/fmt/pull/2020, https://github.com/fmtlib/fmt/pull/2110, https://github.com/fmtlib/fmt/pull/2114, https://github.com/fmtlib/fmt/issues/2196, https://github.com/fmtlib/fmt/pull/2217, https://github.com/fmtlib/fmt/pull/2247, https://github.com/fmtlib/fmt/pull/2256, https://github.com/fmtlib/fmt/pull/2336, https://github.com/fmtlib/fmt/pull/2346). Thanks @jgopel, @alexezeder and @DanielaE.
7.1.3 - 2020-11-24
- Fixed handling of buffer boundaries in
format_to_n
(https://github.com/fmtlib/fmt/issues/1996, https://github.com/fmtlib/fmt/issues/2029). - Fixed linkage errors when linking with a shared library (https://github.com/fmtlib/fmt/issues/2011).
- Reintroduced ostream support to range formatters (https://github.com/fmtlib/fmt/issues/2014).
- Worked around an issue with mixing std versions in gcc (https://github.com/fmtlib/fmt/issues/2017).
7.1.2 - 2020-11-04
- Fixed floating point formatting with large precision (https://github.com/fmtlib/fmt/issues/1976).
7.1.1 - 2020-11-01
- Fixed ABI compatibility with 7.0.x (https://github.com/fmtlib/fmt/issues/1961).
- Added the
FMT_ARM_ABI_COMPATIBILITY
macro to work around ABI incompatibility between GCC and Clang on ARM (https://github.com/fmtlib/fmt/issues/1919). - Worked around a SFINAE bug in GCC 8 (https://github.com/fmtlib/fmt/issues/1957).
- Fixed linkage errors when building with GCC's LTO (https://github.com/fmtlib/fmt/issues/1955).
- Fixed a compilation error when building without
__builtin_clz
or equivalent (https://github.com/fmtlib/fmt/pull/1968). Thanks @tohammer. - Fixed a sign conversion warning (https://github.com/fmtlib/fmt/pull/1964). Thanks @OptoCloud.
7.1.0 - 2020-10-25
-
Switched from Grisu3 to Dragonbox for the default floating-point formatting which gives the shortest decimal representation with round-trip guarantee and correct rounding (https://github.com/fmtlib/fmt/pull/1882, https://github.com/fmtlib/fmt/pull/1887, https://github.com/fmtlib/fmt/pull/1894). This makes {fmt} up to 20-30x faster than common implementations of
std::ostringstream
andsprintf
on dtoa-benchmark and faster than double-conversion and Ryū:It is possible to get even better performance at the cost of larger binary size by compiling with the
FMT_USE_FULL_CACHE_DRAGONBOX
macro set to 1.Thanks @jk-jeon.
-
Added an experimental unsynchronized file output API which, together with format string compilation, can give 5-9 times speed up compared to fprintf on common platforms (godbolt):
#include <fmt/os.h> int main() { auto f = fmt::output_file("guide"); f.print("The answer is {}.", 42); }
-
Added a formatter for
std::chrono::time_point<system_clock>
(https://github.com/fmtlib/fmt/issues/1819, https://github.com/fmtlib/fmt/pull/1837). For example (godbolt):#include <fmt/chrono.h> int main() { auto now = std::chrono::system_clock::now(); fmt::print("The time is {:%H:%M:%S}.\n", now); }
Thanks @adamburgess.
-
Added support for ranges with non-const
begin
/end
tofmt::join
(https://github.com/fmtlib/fmt/issues/1784, https://github.com/fmtlib/fmt/pull/1786). For example (godbolt):#include <fmt/ranges.h> #include <range/v3/view/filter.hpp> int main() { using std::literals::string_literals::operator""s; auto strs = std::array{"a"s, "bb"s, "ccc"s}; auto range = strs | ranges::views::filter( [] (const std::string &x) { return x.size() != 2; } ); fmt::print("{}\n", fmt::join(range, "")); }
prints "accc".
Thanks @tonyelewis.
-
Added a
memory_buffer::append
overload that takes a range (https://github.com/fmtlib/fmt/pull/1806). Thanks @BRevzin. -
Improved handling of single code units in
FMT_COMPILE
. For example:#include <fmt/compile.h> char* f(char* buf) { return fmt::format_to(buf, FMT_COMPILE("x{}"), 42); }
compiles to just (godbolt):
_Z1fPc: movb $120, (%rdi) xorl %edx, %edx cmpl $42, _ZN3fmt2v76detail10basic_dataIvE23zero_or_powers_of_10_32E+8(%rip) movl $3, %eax seta %dl subl %edx, %eax movzwl _ZN3fmt2v76detail10basic_dataIvE6digitsE+84(%rip), %edx cltq addq %rdi, %rax movw %dx, -2(%rax) ret
Here a single
mov
instruction writes'x'
($120
) to the output buffer. -
Added dynamic width support to format string compilation (https://github.com/fmtlib/fmt/issues/1809).
-
Improved error reporting for unformattable types: now you'll get the type name directly in the error message instead of the note:
#include <fmt/core.h> struct how_about_no {}; int main() { fmt::print("{}", how_about_no()); }
Error (godbolt):
fmt/core.h:1438:3: error: static_assert failed due to requirement 'fmt::v7::formattable<how_about_no>()' "Cannot format an argument. To make type T formattable provide a formatter<T> specialization: https://fmt.dev/latest/api.html#udt" ...
-
Added the make_args_checked function template that allows you to write formatting functions with compile-time format string checks and avoid binary code bloat (godbolt):
void vlog(const char* file, int line, fmt::string_view format, fmt::format_args args) { fmt::print("{}: {}: ", file, line); fmt::vprint(format, args); } template <typename S, typename... Args> void log(const char* file, int line, const S& format, Args&&... args) { vlog(file, line, format, fmt::make_args_checked<Args...>(format, args...)); } #define MY_LOG(format, ...) \ log(__FILE__, __LINE__, FMT_STRING(format), __VA_ARGS__) MY_LOG("invalid squishiness: {}", 42);
-
Replaced
snprintf
fallback with a faster internal IEEE 754float
anddouble
formatter for arbitrary precision. For example (godbolt):#include <fmt/core.h> int main() { fmt::print("{:.500}\n", 4.9406564584124654E-324); }
prints
4.9406564584124654417656879286822137236505980261432476442558568250067550727020875186529983636163599237979656469544571773092665671035593979639877479601078187812630071319031140452784581716784898210368871863605699873072305000638740915356498438731247339727316961514003171538539807412623856559117102665855668676818703956031062493194527159149245532930545654440112748012970999954193198940908041656332452475714786901472678015935523861155013480352649347201937902681071074917033322268447533357208324319360923829e-324
. -
Made
format_to_n
andformatted_size
part of the core API (godbolt):#include <fmt/core.h> int main() { char buffer[10]; auto result = fmt::format_to_n(buffer, sizeof(buffer), "{}", 42); }
-
Added
fmt::format_to_n
overload with format string compilation (https://github.com/fmtlib/fmt/issues/1764, https://github.com/fmtlib/fmt/pull/1767, https://github.com/fmtlib/fmt/pull/1869). For example (godbolt):#include <fmt/compile.h> int main() { char buffer[8]; fmt::format_to_n(buffer, sizeof(buffer), FMT_COMPILE("{}"), 42); }
Thanks @Kurkin and @alexezeder.
-
Added
fmt::format_to
overload that taketext_style
(https://github.com/fmtlib/fmt/issues/1593, https://github.com/fmtlib/fmt/issues/1842, https://github.com/fmtlib/fmt/pull/1843). For example (godbolt):#include <fmt/color.h> int main() { std::string out; fmt::format_to(std::back_inserter(out), fmt::emphasis::bold | fg(fmt::color::red), "The answer is {}.", 42); }
Thanks @Naios.
-
Made the
'#'
specifier emit trailing zeros in addition to the decimal point (https://github.com/fmtlib/fmt/issues/1797). For example (godbolt):#include <fmt/core.h> int main() { fmt::print("{:#.2g}", 0.5); }
prints
0.50
. -
Changed the default floating point format to not include
.0
for consistency withstd::format
andstd::to_chars
(https://github.com/fmtlib/fmt/issues/1893, https://github.com/fmtlib/fmt/issues/1943). It is possible to get the decimal point and trailing zero with the#
specifier. -
Fixed an issue with floating-point formatting that could result in addition of a non-significant trailing zero in rare cases e.g.
1.00e-34
instead of1.0e-34
(https://github.com/fmtlib/fmt/issues/1873, https://github.com/fmtlib/fmt/issues/1917). -
Made
fmt::to_string
fallback onostream
insertion operator if theformatter
specialization is not provided (https://github.com/fmtlib/fmt/issues/1815, https://github.com/fmtlib/fmt/pull/1829). Thanks @alexezeder. -
Added support for the append mode to the experimental file API and improved
fcntl.h
detection. (https://github.com/fmtlib/fmt/pull/1847, https://github.com/fmtlib/fmt/pull/1848). Thanks @t-wiser. -
Fixed handling of types that have both an implicit conversion operator and an overloaded
ostream
insertion operator (https://github.com/fmtlib/fmt/issues/1766). -
Fixed a slicing issue in an internal iterator type (https://github.com/fmtlib/fmt/pull/1822). Thanks @BRevzin.
-
Fixed an issue in locale-specific integer formatting (https://github.com/fmtlib/fmt/issues/1927).
-
Fixed handling of exotic code unit types (https://github.com/fmtlib/fmt/issues/1870, https://github.com/fmtlib/fmt/issues/1932).
-
Improved
FMT_ALWAYS_INLINE
(https://github.com/fmtlib/fmt/pull/1878). Thanks @jk-jeon. -
Removed dependency on
windows.h
(https://github.com/fmtlib/fmt/pull/1900). Thanks @bernd5. -
Optimized counting of decimal digits on MSVC (https://github.com/fmtlib/fmt/pull/1890). Thanks @mwinterb.
-
Improved documentation (https://github.com/fmtlib/fmt/issues/1772, https://github.com/fmtlib/fmt/pull/1775, https://github.com/fmtlib/fmt/pull/1792, https://github.com/fmtlib/fmt/pull/1838, https://github.com/fmtlib/fmt/pull/1888, https://github.com/fmtlib/fmt/pull/1918, https://github.com/fmtlib/fmt/pull/1939). Thanks @leolchat, @pepsiman, @Klaim, @ravijanjam, @francesco-st and @udnaan.
-
Added the
FMT_REDUCE_INT_INSTANTIATIONS
CMake option that reduces the binary code size at the cost of some integer formatting performance. This can be useful for extremely memory-constrained embedded systems (https://github.com/fmtlib/fmt/issues/1778, https://github.com/fmtlib/fmt/pull/1781). Thanks @kammce. -
Added the
FMT_USE_INLINE_NAMESPACES
macro to control usage of inline namespaces (https://github.com/fmtlib/fmt/pull/1945). Thanks @darklukee. -
Improved build configuration (https://github.com/fmtlib/fmt/pull/1760, https://github.com/fmtlib/fmt/pull/1770, https://github.com/fmtlib/fmt/issues/1779, https://github.com/fmtlib/fmt/pull/1783, https://github.com/fmtlib/fmt/pull/1823). Thanks @dvetutnev, @xvitaly, @tambry, @medithe and @martinwuehrer.
-
Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/pull/1790, https://github.com/fmtlib/fmt/pull/1802, https://github.com/fmtlib/fmt/pull/1808, https://github.com/fmtlib/fmt/issues/1810, https://github.com/fmtlib/fmt/issues/1811, https://github.com/fmtlib/fmt/pull/1812, https://github.com/fmtlib/fmt/pull/1814, https://github.com/fmtlib/fmt/pull/1816, https://github.com/fmtlib/fmt/pull/1817, https://github.com/fmtlib/fmt/pull/1818, https://github.com/fmtlib/fmt/issues/1825, https://github.com/fmtlib/fmt/pull/1836, https://github.com/fmtlib/fmt/pull/1855, https://github.com/fmtlib/fmt/pull/1856, https://github.com/fmtlib/fmt/pull/1860, https://github.com/fmtlib/fmt/pull/1877, https://github.com/fmtlib/fmt/pull/1879, https://github.com/fmtlib/fmt/pull/1880, https://github.com/fmtlib/fmt/issues/1896, https://github.com/fmtlib/fmt/pull/1897, https://github.com/fmtlib/fmt/pull/1898, https://github.com/fmtlib/fmt/issues/1904, https://github.com/fmtlib/fmt/pull/1908, https://github.com/fmtlib/fmt/issues/1911, https://github.com/fmtlib/fmt/issues/1912, https://github.com/fmtlib/fmt/issues/1928, https://github.com/fmtlib/fmt/pull/1929, https://github.com/fmtlib/fmt/issues/1935, https://github.com/fmtlib/fmt/pull/1937, https://github.com/fmtlib/fmt/pull/1942, https://github.com/fmtlib/fmt/issues/1949). Thanks @TheQwertiest, @medithe, @martinwuehrer, @n16h7hunt3r, @Othereum, @gsjaardema, @AlexanderLanin, @gcerretani, @chronoxor, @noizefloor, @akohlmey, @jk-jeon, @rimathia, @rglarix, @moiwi, @heckad, @MarcDirven. @BartSiwek and @darklukee.
7.0.3 - 2020-08-06
- Worked around broken
numeric_limits
for 128-bit integers (https://github.com/fmtlib/fmt/issues/1787). - Added error reporting on missing named arguments (https://github.com/fmtlib/fmt/issues/1796).
- Stopped using 128-bit integers with clang-cl (https://github.com/fmtlib/fmt/pull/1800). Thanks @Kingcom.
- Fixed issues in locale-specific integer formatting (https://github.com/fmtlib/fmt/issues/1782, https://github.com/fmtlib/fmt/issues/1801).
7.0.2 - 2020-07-29
- Worked around broken
numeric_limits
for 128-bit integers (https://github.com/fmtlib/fmt/issues/1725). - Fixed compatibility with CMake 3.4 (https://github.com/fmtlib/fmt/issues/1779).
- Fixed handling of digit separators in locale-specific formatting (https://github.com/fmtlib/fmt/issues/1782).
7.0.1 - 2020-07-07
- Updated the inline version namespace name.
- Worked around a gcc bug in mangling of alias templates (https://github.com/fmtlib/fmt/issues/1753).
- Fixed a linkage error on Windows (https://github.com/fmtlib/fmt/issues/1757). Thanks @Kurkin.
- Fixed minor issues with the documentation.
7.0.0 - 2020-07-05
-
Reduced the library size. For example, on macOS a stripped test binary statically linked with {fmt} shrank from ~368k to less than 100k.
-
Added a simpler and more efficient format string compilation API:
#include <fmt/compile.h> // Converts 42 into std::string using the most efficient method and no // runtime format string processing. std::string s = fmt::format(FMT_COMPILE("{}"), 42);
The old
fmt::compile
API is now deprecated. -
Optimized integer formatting:
format_to
with format string compilation and a stack-allocated buffer is now faster than to_chars on both libc++ and libstdc++. -
Optimized handling of small format strings. For example,
fmt::format("Result: {}: ({},{},{},{})", str1, str2, str3, str4, str5)
is now ~40% faster (https://github.com/fmtlib/fmt/issues/1685).
-
Applied extern templates to improve compile times when using the core API and
fmt/format.h
(https://github.com/fmtlib/fmt/issues/1452). For example, on macOS with clang the compile time of a test translation unit dropped from 2.3s to 0.3s with-O2
and from 0.6s to 0.3s with the default settings (-O0
).Before (
-O2
):% time c++ -c test.cc -I include -std=c++17 -O2 c++ -c test.cc -I include -std=c++17 -O2 2.22s user 0.08s system 99% cpu 2.311 total
After (
-O2
):% time c++ -c test.cc -I include -std=c++17 -O2 c++ -c test.cc -I include -std=c++17 -O2 0.26s user 0.04s system 98% cpu 0.303 total
Before (default):
% time c++ -c test.cc -I include -std=c++17 c++ -c test.cc -I include -std=c++17 0.53s user 0.06s system 98% cpu 0.601 total
After (default):
% time c++ -c test.cc -I include -std=c++17 c++ -c test.cc -I include -std=c++17 0.24s user 0.06s system 98% cpu 0.301 total
It is still recommended to use
fmt/core.h
instead offmt/format.h
but the compile time difference is now smaller. Thanks @alex3d for the suggestion. -
Named arguments are now stored on stack (no dynamic memory allocations) and the compiled code is more compact and efficient. For example
#include <fmt/core.h> int main() { fmt::print("The answer is {answer}\n", fmt::arg("answer", 42)); }
compiles to just (godbolt)
.LC0: .string "answer" .LC1: .string "The answer is {answer}\n" main: sub rsp, 56 mov edi, OFFSET FLAT:.LC1 mov esi, 23 movabs rdx, 4611686018427387905 lea rax, [rsp+32] lea rcx, [rsp+16] mov QWORD PTR [rsp+8], 1 mov QWORD PTR [rsp], rax mov DWORD PTR [rsp+16], 42 mov QWORD PTR [rsp+32], OFFSET FLAT:.LC0 mov DWORD PTR [rsp+40], 0 call fmt::v6::vprint(fmt::v6::basic_string_view<char>, fmt::v6::format_args) xor eax, eax add rsp, 56 ret .L.str.1: .asciz "answer"
-
Implemented compile-time checks for dynamic width and precision (https://github.com/fmtlib/fmt/issues/1614):
#include <fmt/format.h> int main() { fmt::print(FMT_STRING("{0:{1}}"), 42); }
now gives a compilation error because argument 1 doesn't exist:
In file included from test.cc:1: include/fmt/format.h:2726:27: error: constexpr variable 'invalid_format' must be initialized by a constant expression FMT_CONSTEXPR_DECL bool invalid_format = ^ ... include/fmt/core.h:569:26: note: in call to '&checker(s, {}).context_->on_error(&"argument not found"[0])' if (id >= num_args_) on_error("argument not found"); ^
-
Added sentinel support to
fmt::join
(https://github.com/fmtlib/fmt/pull/1689)struct zstring_sentinel {}; bool operator==(const char* p, zstring_sentinel) { return *p == '\0'; } bool operator!=(const char* p, zstring_sentinel) { return *p != '\0'; } struct zstring { const char* p; const char* begin() const { return p; } zstring_sentinel end() const { return {}; } }; auto s = fmt::format("{}", fmt::join(zstring{"hello"}, "_")); // s == "h_e_l_l_o"
Thanks @BRevzin.
-
Added support for named arguments,
clear
andreserve
todynamic_format_arg_store
(https://github.com/fmtlib/fmt/issues/1655, https://github.com/fmtlib/fmt/pull/1663, https://github.com/fmtlib/fmt/pull/1674, https://github.com/fmtlib/fmt/pull/1677). Thanks @vsolontsov-ll. -
Added support for the
'c'
format specifier to integral types for compatibility withstd::format
(https://github.com/fmtlib/fmt/issues/1652). -
Replaced the
'n'
format specifier with'L'
for compatibility withstd::format
(https://github.com/fmtlib/fmt/issues/1624). The'n'
specifier can be enabled via theFMT_DEPRECATED_N_SPECIFIER
macro. -
The
'='
format specifier is now disabled by default for compatibility withstd::format
. It can be enabled via theFMT_DEPRECATED_NUMERIC_ALIGN
macro. -
Removed the following deprecated APIs:
FMT_STRING_ALIAS
andfmt
macros - replaced byFMT_STRING
fmt::basic_string_view::char_type
- replaced byfmt::basic_string_view::value_type
convert_to_int
format_arg_store::types
*parse_context
- replaced by*format_parse_context
FMT_DEPRECATED_INCLUDE_OS
FMT_DEPRECATED_PERCENT
- incompatible withstd::format
*writer
- replaced by compiled format API
-
Renamed the
internal
namespace todetail
(https://github.com/fmtlib/fmt/issues/1538). The former is still provided as an alias if theFMT_USE_INTERNAL
macro is defined. -
Improved compatibility between
fmt::printf
with the standard specs (https://github.com/fmtlib/fmt/issues/1595, https://github.com/fmtlib/fmt/pull/1682, https://github.com/fmtlib/fmt/pull/1683, https://github.com/fmtlib/fmt/pull/1687, https://github.com/fmtlib/fmt/pull/1699). Thanks @rimathia. -
Fixed handling of
operator<<
overloads that usecopyfmt
(https://github.com/fmtlib/fmt/issues/1666). -
Added the
FMT_OS
CMake option to control inclusion of OS-specific APIs in the fmt target. This can be useful for embedded platforms (https://github.com/fmtlib/fmt/issues/1654, https://github.com/fmtlib/fmt/pull/1656). Thanks @kwesolowski. -
Replaced
FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
with theFMT_FUZZ
macro to prevent interfering with fuzzing of projects using {fmt} (https://github.com/fmtlib/fmt/pull/1650). Thanks @asraa. -
Fixed compatibility with emscripten (https://github.com/fmtlib/fmt/issues/1636, https://github.com/fmtlib/fmt/pull/1637). Thanks @ArthurSonzogni.
-
Improved documentation (https://github.com/fmtlib/fmt/issues/704, https://github.com/fmtlib/fmt/pull/1643, https://github.com/fmtlib/fmt/pull/1660, https://github.com/fmtlib/fmt/pull/1681, https://github.com/fmtlib/fmt/pull/1691, https://github.com/fmtlib/fmt/pull/1706, https://github.com/fmtlib/fmt/pull/1714, https://github.com/fmtlib/fmt/pull/1721, https://github.com/fmtlib/fmt/pull/1739, https://github.com/fmtlib/fmt/pull/1740, https://github.com/fmtlib/fmt/pull/1741, https://github.com/fmtlib/fmt/pull/1751). Thanks @senior7515, @lsr0, @puetzk, @fpelliccioni, Alexey Kuzmenko, @jelly, @claremacrae, @jiapengwen, @gsjaardema and @alexey-milovidov.
-
Implemented various build configuration fixes and improvements (https://github.com/fmtlib/fmt/pull/1603, https://github.com/fmtlib/fmt/pull/1657, https://github.com/fmtlib/fmt/pull/1702, https://github.com/fmtlib/fmt/pull/1728). Thanks @scramsby, @jtojnar, @orivej and @flagarde.
-
Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/pull/1616, https://github.com/fmtlib/fmt/issues/1620, https://github.com/fmtlib/fmt/issues/1622, https://github.com/fmtlib/fmt/issues/1625, https://github.com/fmtlib/fmt/pull/1627, https://github.com/fmtlib/fmt/issues/1628, https://github.com/fmtlib/fmt/pull/1629, https://github.com/fmtlib/fmt/issues/1631, https://github.com/fmtlib/fmt/pull/1633, https://github.com/fmtlib/fmt/pull/1649, https://github.com/fmtlib/fmt/issues/1658, https://github.com/fmtlib/fmt/pull/1661, https://github.com/fmtlib/fmt/pull/1667, https://github.com/fmtlib/fmt/issues/1668, https://github.com/fmtlib/fmt/pull/1669, https://github.com/fmtlib/fmt/issues/1692, https://github.com/fmtlib/fmt/pull/1696, https://github.com/fmtlib/fmt/pull/1697, https://github.com/fmtlib/fmt/issues/1707, https://github.com/fmtlib/fmt/pull/1712, https://github.com/fmtlib/fmt/pull/1716, https://github.com/fmtlib/fmt/pull/1722, https://github.com/fmtlib/fmt/issues/1724, https://github.com/fmtlib/fmt/pull/1729, https://github.com/fmtlib/fmt/pull/1738, https://github.com/fmtlib/fmt/issues/1742, https://github.com/fmtlib/fmt/issues/1743, https://github.com/fmtlib/fmt/pull/1744, https://github.com/fmtlib/fmt/issues/1747, https://github.com/fmtlib/fmt/pull/1750). Thanks @gsjaardema, @gabime, @johnor, @Kurkin, @invexed, @peterbell10, @daixtrose, @petrutlucian94, @Neargye, @ambitslix, @gabime, @erthink, @tohammer and @0x8000-0000.
6.2.1 - 2020-05-09
- Fixed ostream support in
sprintf
(https://github.com/fmtlib/fmt/issues/1631). - Fixed type detection when using implicit conversion to
string_view
and ostreamoperator<<
inconsistently (https://github.com/fmtlib/fmt/issues/1662).
6.2.0 - 2020-04-05
-
Improved error reporting when trying to format an object of a non-formattable type:
fmt::format("{}", S());
now gives:
include/fmt/core.h:1015:5: error: static_assert failed due to requirement 'formattable' "Cannot format argument. To make type T formattable provide a formatter<T> specialization: https://fmt.dev/latest/api.html#formatting-user-defined-types" static_assert( ^ ... note: in instantiation of function template specialization 'fmt::v6::format<char [3], S, char>' requested here fmt::format("{}", S()); ^
if
S
is not formattable. -
Reduced the library size by ~10%.
-
Always print decimal point if
#
is specified (https://github.com/fmtlib/fmt/issues/1476, https://github.com/fmtlib/fmt/issues/1498):fmt::print("{:#.0f}", 42.0);
now prints
42.
-
Implemented the
'L'
specifier for locale-specific numeric formatting to improve compatibility withstd::format
. The'n'
specifier is now deprecated and will be removed in the next major release. -
Moved OS-specific APIs such as
windows_error
fromfmt/format.h
tofmt/os.h
. You can defineFMT_DEPRECATED_INCLUDE_OS
to automatically includefmt/os.h
fromfmt/format.h
for compatibility but this will be disabled in the next major release. -
Added precision overflow detection in floating-point formatting.
-
Implemented detection of invalid use of
fmt::arg
. -
Used
type_identity
to block unnecessary template argument deduction. Thanks Tim Song. -
Improved UTF-8 handling (https://github.com/fmtlib/fmt/issues/1109):
fmt::print("┌{0:─^{2}}┐\n" "│{1: ^{2}}│\n" "└{0:─^{2}}┘\n", "", "Привет, мир!", 20);
now prints:
┌────────────────────┐ │ Привет, мир! │ └────────────────────┘
on systems that support Unicode.
-
Added experimental dynamic argument storage (https://github.com/fmtlib/fmt/issues/1170, https://github.com/fmtlib/fmt/pull/1584):
fmt::dynamic_format_arg_store<fmt::format_context> store; store.push_back("answer"); store.push_back(42); fmt::vprint("The {} is {}.\n", store);
prints:
The answer is 42.
Thanks @vsolontsov-ll.
-
Made
fmt::join
acceptinitializer_list
(https://github.com/fmtlib/fmt/pull/1591). Thanks @Rapotkinnik. -
Fixed handling of empty tuples (https://github.com/fmtlib/fmt/issues/1588).
-
Fixed handling of output iterators in
format_to_n
(https://github.com/fmtlib/fmt/issues/1506). -
Fixed formatting of
std::chrono::duration
types to wide output (https://github.com/fmtlib/fmt/pull/1533). Thanks @zeffy. -
Added const
begin
andend
overload to buffers (https://github.com/fmtlib/fmt/pull/1553). Thanks @dominicpoeschko. -
Added the ability to disable floating-point formatting via
FMT_USE_FLOAT
,FMT_USE_DOUBLE
andFMT_USE_LONG_DOUBLE
macros for extremely memory-constrained embedded system (https://github.com/fmtlib/fmt/pull/1590). Thanks @albaguirre. -
Made
FMT_STRING
work withconstexpr
string_view
(https://github.com/fmtlib/fmt/pull/1589). Thanks @scramsby. -
Implemented a minor optimization in the format string parser (https://github.com/fmtlib/fmt/pull/1560). Thanks @IkarusDeveloper.
-
Improved attribute detection (https://github.com/fmtlib/fmt/pull/1469, https://github.com/fmtlib/fmt/pull/1475, https://github.com/fmtlib/fmt/pull/1576). Thanks @federico-busato, @chronoxor and @refnum.
-
Improved documentation (https://github.com/fmtlib/fmt/pull/1481, https://github.com/fmtlib/fmt/pull/1523). Thanks @JackBoosY and @imba-tjd.
-
Fixed symbol visibility on Linux when compiling with
-fvisibility=hidden
(https://github.com/fmtlib/fmt/pull/1535). Thanks @milianw. -
Implemented various build configuration fixes and improvements (https://github.com/fmtlib/fmt/issues/1264, https://github.com/fmtlib/fmt/issues/1460, https://github.com/fmtlib/fmt/pull/1534, https://github.com/fmtlib/fmt/issues/1536, https://github.com/fmtlib/fmt/issues/1545, https://github.com/fmtlib/fmt/pull/1546, https://github.com/fmtlib/fmt/issues/1566, https://github.com/fmtlib/fmt/pull/1582, https://github.com/fmtlib/fmt/issues/1597, https://github.com/fmtlib/fmt/pull/1598). Thanks @ambitslix, @jwillikers and @stac47.
-
Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/pull/1433, https://github.com/fmtlib/fmt/issues/1461, https://github.com/fmtlib/fmt/pull/1470, https://github.com/fmtlib/fmt/pull/1480, https://github.com/fmtlib/fmt/pull/1485, https://github.com/fmtlib/fmt/pull/1492, https://github.com/fmtlib/fmt/issues/1493, https://github.com/fmtlib/fmt/issues/1504, https://github.com/fmtlib/fmt/pull/1505, https://github.com/fmtlib/fmt/pull/1512, https://github.com/fmtlib/fmt/issues/1515, https://github.com/fmtlib/fmt/pull/1516, https://github.com/fmtlib/fmt/pull/1518, https://github.com/fmtlib/fmt/pull/1519, https://github.com/fmtlib/fmt/pull/1520, https://github.com/fmtlib/fmt/pull/1521, https://github.com/fmtlib/fmt/pull/1522, https://github.com/fmtlib/fmt/issues/1524, https://github.com/fmtlib/fmt/pull/1530, https://github.com/fmtlib/fmt/issues/1531, https://github.com/fmtlib/fmt/pull/1532, https://github.com/fmtlib/fmt/issues/1539, https://github.com/fmtlib/fmt/issues/1547, https://github.com/fmtlib/fmt/issues/1548, https://github.com/fmtlib/fmt/pull/1554, https://github.com/fmtlib/fmt/issues/1567, https://github.com/fmtlib/fmt/pull/1568, https://github.com/fmtlib/fmt/pull/1569, https://github.com/fmtlib/fmt/pull/1571, https://github.com/fmtlib/fmt/pull/1573, https://github.com/fmtlib/fmt/pull/1575, https://github.com/fmtlib/fmt/pull/1581, https://github.com/fmtlib/fmt/issues/1583, https://github.com/fmtlib/fmt/issues/1586, https://github.com/fmtlib/fmt/issues/1587, https://github.com/fmtlib/fmt/issues/1594, https://github.com/fmtlib/fmt/pull/1596, https://github.com/fmtlib/fmt/issues/1604, https://github.com/fmtlib/fmt/pull/1606, https://github.com/fmtlib/fmt/issues/1607, https://github.com/fmtlib/fmt/issues/1609). Thanks @marti4d, @iPherian, @parkertomatoes, @gsjaardema, @chronoxor, @DanielaE, @torsten48, @tohammer, @lefticus, @ryusakki, @adnsv, @fghzxm, @refnum, @pramodk, @Spirrwell and @scramsby.
6.1.2 - 2019-12-11
- Fixed ABI compatibility with
libfmt.so.6.0.0
(https://github.com/fmtlib/fmt/issues/1471). - Fixed handling types convertible to
std::string_view
(https://github.com/fmtlib/fmt/pull/1451). Thanks @denizevrenci. - Made CUDA test an opt-in enabled via the
FMT_CUDA_TEST
CMake option. - Fixed sign conversion warnings (https://github.com/fmtlib/fmt/pull/1440). Thanks @0x8000-0000.
6.1.1 - 2019-12-04
- Fixed shared library build on Windows (https://github.com/fmtlib/fmt/pull/1443, https://github.com/fmtlib/fmt/issues/1445, https://github.com/fmtlib/fmt/pull/1446, https://github.com/fmtlib/fmt/issues/1450). Thanks @egorpugin and @bbolli.
- Added a missing decimal point in exponent notation with trailing zeros.
- Removed deprecated
format_arg_store::TYPES
.
6.1.0 - 2019-12-01
-
{fmt} now formats IEEE 754
float
anddouble
using the shortest decimal representation with correct rounding by default:#include <cmath> #include <fmt/core.h> int main() { fmt::print("{}", M_PI); }
prints
3.141592653589793
. -
Made the fast binary to decimal floating-point formatter the default, simplified it and improved performance. {fmt} is now 15 times faster than libc++'s
std::ostringstream
, 11 times faster thanprintf
and 10% faster than double-conversion on dtoa-benchmark:Function Time (ns) Speedup ostringstream 1,346.30 1.00x ostrstream 1,195.74 1.13x sprintf 995.08 1.35x doubleconv 99.10 13.59x fmt 88.34 15.24x -
{fmt} no longer converts
float
arguments todouble
. In particular this improves the default (shortest) representation of floats and makesfmt::format
consistent withstd::format
specs (https://github.com/fmtlib/fmt/issues/1336, https://github.com/fmtlib/fmt/issues/1353, https://github.com/fmtlib/fmt/pull/1360, https://github.com/fmtlib/fmt/pull/1361):fmt::print("{}", 0.1f);
prints
0.1
instead of0.10000000149011612
.Thanks @orivej.
-
Made floating-point formatting output consistent with
printf
/iostreams (https://github.com/fmtlib/fmt/issues/1376, https://github.com/fmtlib/fmt/issues/1417). -
Added support for 128-bit integers (https://github.com/fmtlib/fmt/pull/1287):
fmt::print("{}", std::numeric_limits<__int128_t>::max());
prints
170141183460469231731687303715884105727
.Thanks @denizevrenci.
-
The overload of
print
that takestext_style
is now atomic, i.e. the output from different threads doesn't interleave (https://github.com/fmtlib/fmt/pull/1351). Thanks @tankiJong. -
Made compile time in the header-only mode ~20% faster by reducing the number of template instantiations.
wchar_t
overload ofvprint
was moved fromfmt/core.h
tofmt/format.h
. -
Added an overload of
fmt::join
that works with tuples (https://github.com/fmtlib/fmt/issues/1322, https://github.com/fmtlib/fmt/pull/1330):#include <tuple> #include <fmt/ranges.h> int main() { std::tuple<char, int, float> t{'a', 1, 2.0f}; fmt::print("{}", t); }
prints
('a', 1, 2.0)
.Thanks @jeremyong.
-
Changed formatting of octal zero with prefix from "00" to "0":
fmt::print("{:#o}", 0);
prints
0
. -
The locale is now passed to ostream insertion (
<<
) operators (https://github.com/fmtlib/fmt/pull/1406):#include <fmt/locale.h> #include <fmt/ostream.h> struct S { double value; }; std::ostream& operator<<(std::ostream& os, S s) { return os << s.value; } int main() { auto s = fmt::format(std::locale("fr_FR.UTF-8"), "{}", S{0.42}); // s == "0,42" }
Thanks @dlaugt.
-
Locale-specific number formatting now uses grouping (https://github.com/fmtlib/fmt/issues/1393, https://github.com/fmtlib/fmt/pull/1394). Thanks @skrdaniel.
-
Fixed handling of types with deleted implicit rvalue conversion to
const char**
(https://github.com/fmtlib/fmt/issues/1421):struct mystring { operator const char*() const&; operator const char*() &; operator const char*() const&& = delete; operator const char*() && = delete; }; mystring str; fmt::print("{}", str); // now compiles
-
Enums are now mapped to correct underlying types instead of
int
(https://github.com/fmtlib/fmt/pull/1286). Thanks @agmt. -
Enum classes are no longer implicitly converted to
int
(https://github.com/fmtlib/fmt/issues/1424). -
Added
basic_format_parse_context
for consistency with C++20std::format
and deprecatedbasic_parse_context
. -
Fixed handling of UTF-8 in precision (https://github.com/fmtlib/fmt/issues/1389, https://github.com/fmtlib/fmt/pull/1390). Thanks @tajtiattila.
-
{fmt} can now be installed on Linux, macOS and Windows with Conda using its conda-forge package (https://github.com/fmtlib/fmt/pull/1410):
conda install -c conda-forge fmt
Thanks @tdegeus.
-
Added a CUDA test (https://github.com/fmtlib/fmt/pull/1285, https://github.com/fmtlib/fmt/pull/1317). Thanks @luncliff and @risa2000.
-
Improved documentation (https://github.com/fmtlib/fmt/pull/1276, https://github.com/fmtlib/fmt/issues/1291, https://github.com/fmtlib/fmt/issues/1296, https://github.com/fmtlib/fmt/pull/1315, https://github.com/fmtlib/fmt/pull/1332, https://github.com/fmtlib/fmt/pull/1337, https://github.com/fmtlib/fmt/issues/1395 https://github.com/fmtlib/fmt/pull/1418). Thanks @waywardmonkeys, @pauldreik and @jackoalan.
-
Various code improvements (https://github.com/fmtlib/fmt/pull/1358, https://github.com/fmtlib/fmt/pull/1407). Thanks @orivej and @dpacbach.
-
Fixed compile-time format string checks for user-defined types (https://github.com/fmtlib/fmt/issues/1292).
-
Worked around a false positive in
unsigned-integer-overflow
sanitizer (https://github.com/fmtlib/fmt/issues/1377). -
Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/issues/1273, https://github.com/fmtlib/fmt/pull/1278, https://github.com/fmtlib/fmt/pull/1280, https://github.com/fmtlib/fmt/issues/1281, https://github.com/fmtlib/fmt/issues/1288, https://github.com/fmtlib/fmt/pull/1290, https://github.com/fmtlib/fmt/pull/1301, https://github.com/fmtlib/fmt/issues/1305, https://github.com/fmtlib/fmt/issues/1306, https://github.com/fmtlib/fmt/issues/1309, https://github.com/fmtlib/fmt/pull/1312, https://github.com/fmtlib/fmt/issues/1313, https://github.com/fmtlib/fmt/issues/1316, https://github.com/fmtlib/fmt/issues/1319, https://github.com/fmtlib/fmt/pull/1320, https://github.com/fmtlib/fmt/pull/1326, https://github.com/fmtlib/fmt/pull/1328, https://github.com/fmtlib/fmt/issues/1344, https://github.com/fmtlib/fmt/pull/1345, https://github.com/fmtlib/fmt/pull/1347, https://github.com/fmtlib/fmt/pull/1349, https://github.com/fmtlib/fmt/issues/1354, https://github.com/fmtlib/fmt/issues/1362, https://github.com/fmtlib/fmt/issues/1366, https://github.com/fmtlib/fmt/pull/1364, https://github.com/fmtlib/fmt/pull/1370, https://github.com/fmtlib/fmt/pull/1371, https://github.com/fmtlib/fmt/issues/1385, https://github.com/fmtlib/fmt/issues/1388, https://github.com/fmtlib/fmt/pull/1397, https://github.com/fmtlib/fmt/pull/1414, https://github.com/fmtlib/fmt/pull/1416, https://github.com/fmtlib/fmt/issues/1422 https://github.com/fmtlib/fmt/pull/1427, https://github.com/fmtlib/fmt/issues/1431, https://github.com/fmtlib/fmt/pull/1433). Thanks @hhb, @gsjaardema, @gabime, @neheb, @vedranmiletic, @dkavolis, @mwinterb, @orivej, @denizevrenci, @leonklingele, @chronoxor, @kent-tri, @0x8000-0000 and @marti4d.
6.0.0 - 2019-08-26
-
Switched to the MIT license with an optional exception that allows distributing binary code without attribution.
-
Floating-point formatting is now locale-independent by default:
#include <locale> #include <fmt/core.h> int main() { std::locale::global(std::locale("ru_RU.UTF-8")); fmt::print("value = {}", 4.2); }
prints "value = 4.2" regardless of the locale.
For locale-specific formatting use the
n
specifier:std::locale::global(std::locale("ru_RU.UTF-8")); fmt::print("value = {:n}", 4.2);
prints "value = 4,2".
-
Added an experimental Grisu floating-point formatting algorithm implementation (disabled by default). To enable it compile with the
FMT_USE_GRISU
macro defined to 1:#define FMT_USE_GRISU 1 #include <fmt/format.h> auto s = fmt::format("{}", 4.2); // formats 4.2 using Grisu
With Grisu enabled, {fmt} is 13x faster than
std::ostringstream
(libc++) and 10x faster thansprintf
on dtoa-benchmark (full results): -
Separated formatting and parsing contexts for consistency with C++20 std::format, removing the undocumented
basic_format_context::parse_context()
function. -
Added oss-fuzz support (https://github.com/fmtlib/fmt/pull/1199). Thanks @pauldreik.
-
formatter
specializations now always take precedence overoperator<<
(https://github.com/fmtlib/fmt/issues/952):#include <iostream> #include <fmt/ostream.h> struct S {}; std::ostream& operator<<(std::ostream& os, S) { return os << 1; } template <> struct fmt::formatter<S> : fmt::formatter<int> { auto format(S, format_context& ctx) { return formatter<int>::format(2, ctx); } }; int main() { std::cout << S() << "\n"; // prints 1 using operator<< fmt::print("{}\n", S()); // prints 2 using formatter }
-
Introduced the experimental
fmt::compile
function that does format string compilation (https://github.com/fmtlib/fmt/issues/618, https://github.com/fmtlib/fmt/issues/1169, https://github.com/fmtlib/fmt/pull/1171):#include <fmt/compile.h> auto f = fmt::compile<int>("{}"); std::string s = fmt::format(f, 42); // can be called multiple times to // format different values // s == "42"
It moves the cost of parsing a format string outside of the format function which can be beneficial when identically formatting many objects of the same types. Thanks @stryku.
-
Added experimental
%
format specifier that formats floating-point values as percentages (https://github.com/fmtlib/fmt/pull/1060, https://github.com/fmtlib/fmt/pull/1069, https://github.com/fmtlib/fmt/pull/1071):auto s = fmt::format("{:.1%}", 0.42); // s == "42.0%"
Thanks @gawain-bolton.
-
Implemented precision for floating-point durations (https://github.com/fmtlib/fmt/issues/1004, https://github.com/fmtlib/fmt/pull/1012):
auto s = fmt::format("{:.1}", std::chrono::duration<double>(1.234)); // s == 1.2s
Thanks @DanielaE.
-
Implemented
chrono
format specifiers%Q
and%q
that give the value and the unit respectively (https://github.com/fmtlib/fmt/pull/1019):auto value = fmt::format("{:%Q}", 42s); // value == "42" auto unit = fmt::format("{:%q}", 42s); // unit == "s"
Thanks @DanielaE.
-
Fixed handling of dynamic width in chrono formatter:
auto s = fmt::format("{0:{1}%H:%M:%S}", std::chrono::seconds(12345), 12); // ^ width argument index ^ width // s == "03:25:45 "
Thanks Howard Hinnant.
-
Removed deprecated
fmt/time.h
. Usefmt/chrono.h
instead. -
Added
fmt::format
andfmt::vformat
overloads that taketext_style
(https://github.com/fmtlib/fmt/issues/993, https://github.com/fmtlib/fmt/pull/994):#include <fmt/color.h> std::string message = fmt::format(fmt::emphasis::bold | fg(fmt::color::red), "The answer is {}.", 42);
Thanks @Naios.
-
Removed the deprecated color API (
print_colored
). Use the new API, namelyprint
overloads that taketext_style
instead. -
Made
std::unique_ptr
andstd::shared_ptr
formattable as pointers viafmt::ptr
(https://github.com/fmtlib/fmt/pull/1121):std::unique_ptr<int> p = ...; fmt::print("{}", fmt::ptr(p)); // prints p as a pointer
Thanks @sighingnow.
-
Made
print
andvprint
report I/O errors (https://github.com/fmtlib/fmt/issues/1098, https://github.com/fmtlib/fmt/pull/1099). Thanks @BillyDonahue. -
Marked deprecated APIs with the
[[deprecated]]
attribute and removed internal uses of deprecated APIs (https://github.com/fmtlib/fmt/pull/1022). Thanks @eliaskosunen. -
Modernized the codebase using more C++11 features and removing workarounds. Most importantly,
buffer_context
is now an alias template, so usebuffer_context<T>
instead ofbuffer_context<T>::type
. These features require GCC 4.8 or later. -
formatter
specializations now always take precedence over implicit conversions toint
and the undocumentedconvert_to_int
trait is now deprecated. -
Moved the undocumented
basic_writer
,writer
, andwwriter
types to theinternal
namespace. -
Removed deprecated
basic_format_context::begin()
. Useout()
instead. -
Disallowed passing the result of
join
as an lvalue to prevent misuse. -
Refactored the undocumented structs that represent parsed format specifiers to simplify the API and allow multibyte fill.
-
Moved SFINAE to template parameters to reduce symbol sizes.
-
Switched to
fputws
for writing wide strings so that it's no longer required to call_setmode
on Windows (https://github.com/fmtlib/fmt/issues/1229, https://github.com/fmtlib/fmt/pull/1243). Thanks @jackoalan. -
Improved literal-based API (https://github.com/fmtlib/fmt/pull/1254). Thanks @sylveon.
-
Added support for exotic platforms without
uintptr_t
such as IBM i (AS/400) which has 128-bit pointers and only 64-bit integers (https://github.com/fmtlib/fmt/issues/1059). -
Added Sublime Text syntax highlighting config (https://github.com/fmtlib/fmt/issues/1037). Thanks @Kronuz.
-
Added the
FMT_ENFORCE_COMPILE_STRING
macro to enforce the use of compile-time format strings (https://github.com/fmtlib/fmt/pull/1231). Thanks @jackoalan. -
Stopped setting
CMAKE_BUILD_TYPE
if {fmt} is a subproject (https://github.com/fmtlib/fmt/issues/1081). -
Various build improvements (https://github.com/fmtlib/fmt/pull/1039, https://github.com/fmtlib/fmt/pull/1078, https://github.com/fmtlib/fmt/pull/1091, https://github.com/fmtlib/fmt/pull/1103, https://github.com/fmtlib/fmt/pull/1177). Thanks @luncliff, @jasonszang, @olafhering, @Lecetem and @pauldreik.
-
Improved documentation (https://github.com/fmtlib/fmt/issues/1049, https://github.com/fmtlib/fmt/pull/1051, https://github.com/fmtlib/fmt/pull/1083, https://github.com/fmtlib/fmt/pull/1113, https://github.com/fmtlib/fmt/pull/1114, https://github.com/fmtlib/fmt/issues/1146, https://github.com/fmtlib/fmt/issues/1180, https://github.com/fmtlib/fmt/pull/1250, https://github.com/fmtlib/fmt/pull/1252, https://github.com/fmtlib/fmt/pull/1265). Thanks @mikelui, @foonathan, @BillyDonahue, @jwakely, @kaisbe and @sdebionne.
-
Fixed ambiguous formatter specialization in
fmt/ranges.h
(https://github.com/fmtlib/fmt/issues/1123). -
Fixed formatting of a non-empty
std::filesystem::path
which is an infinitely deep range of its components (https://github.com/fmtlib/fmt/issues/1268). -
Fixed handling of general output iterators when formatting characters (https://github.com/fmtlib/fmt/issues/1056, https://github.com/fmtlib/fmt/pull/1058). Thanks @abolz.
-
Fixed handling of output iterators in
formatter
specialization for ranges (https://github.com/fmtlib/fmt/issues/1064). -
Fixed handling of exotic character types (https://github.com/fmtlib/fmt/issues/1188).
-
Made chrono formatting work with exceptions disabled (https://github.com/fmtlib/fmt/issues/1062).
-
Fixed DLL visibility issues (https://github.com/fmtlib/fmt/pull/1134, https://github.com/fmtlib/fmt/pull/1147). Thanks @denchat.
-
Disabled the use of UDL template extension on GCC 9 (https://github.com/fmtlib/fmt/issues/1148).
-
Removed misplaced
format
compile-time checks fromprintf
(https://github.com/fmtlib/fmt/issues/1173). -
Fixed issues in the experimental floating-point formatter (https://github.com/fmtlib/fmt/issues/1072, https://github.com/fmtlib/fmt/issues/1129, https://github.com/fmtlib/fmt/issues/1153, https://github.com/fmtlib/fmt/pull/1155, https://github.com/fmtlib/fmt/issues/1210, https://github.com/fmtlib/fmt/issues/1222). Thanks @alabuzhev.
-
Fixed bugs discovered by fuzzing or during fuzzing integration (https://github.com/fmtlib/fmt/issues/1124, https://github.com/fmtlib/fmt/issues/1127, https://github.com/fmtlib/fmt/issues/1132, https://github.com/fmtlib/fmt/pull/1135, https://github.com/fmtlib/fmt/issues/1136, https://github.com/fmtlib/fmt/issues/1141, https://github.com/fmtlib/fmt/issues/1142, https://github.com/fmtlib/fmt/issues/1178, https://github.com/fmtlib/fmt/issues/1179, https://github.com/fmtlib/fmt/issues/1194). Thanks @pauldreik.
-
Fixed building tests on FreeBSD and Hurd (https://github.com/fmtlib/fmt/issues/1043). Thanks @jackyf.
-
Fixed various warnings and compilation issues (https://github.com/fmtlib/fmt/pull/998, https://github.com/fmtlib/fmt/pull/1006, https://github.com/fmtlib/fmt/issues/1008, https://github.com/fmtlib/fmt/issues/1011, https://github.com/fmtlib/fmt/issues/1025, https://github.com/fmtlib/fmt/pull/1027, https://github.com/fmtlib/fmt/pull/1028, https://github.com/fmtlib/fmt/pull/1029, https://github.com/fmtlib/fmt/pull/1030, https://github.com/fmtlib/fmt/pull/1031, https://github.com/fmtlib/fmt/pull/1054, https://github.com/fmtlib/fmt/issues/1063, https://github.com/fmtlib/fmt/pull/1068, https://github.com/fmtlib/fmt/pull/1074, https://github.com/fmtlib/fmt/pull/1075, https://github.com/fmtlib/fmt/pull/1079, https://github.com/fmtlib/fmt/pull/1086, https://github.com/fmtlib/fmt/issues/1088, https://github.com/fmtlib/fmt/pull/1089, https://github.com/fmtlib/fmt/pull/1094, https://github.com/fmtlib/fmt/issues/1101, https://github.com/fmtlib/fmt/pull/1102, https://github.com/fmtlib/fmt/issues/1105, https://github.com/fmtlib/fmt/pull/1107, https://github.com/fmtlib/fmt/issues/1115, https://github.com/fmtlib/fmt/issues/1117, https://github.com/fmtlib/fmt/issues/1118, https://github.com/fmtlib/fmt/issues/1120, https://github.com/fmtlib/fmt/issues/1123, https://github.com/fmtlib/fmt/pull/1139, https://github.com/fmtlib/fmt/issues/1140, https://github.com/fmtlib/fmt/issues/1143, https://github.com/fmtlib/fmt/pull/1144, https://github.com/fmtlib/fmt/pull/1150, https://github.com/fmtlib/fmt/pull/1151, https://github.com/fmtlib/fmt/issues/1152, https://github.com/fmtlib/fmt/issues/1154, https://github.com/fmtlib/fmt/issues/1156, https://github.com/fmtlib/fmt/pull/1159, https://github.com/fmtlib/fmt/issues/1175, https://github.com/fmtlib/fmt/issues/1181, https://github.com/fmtlib/fmt/issues/1186, https://github.com/fmtlib/fmt/pull/1187, https://github.com/fmtlib/fmt/pull/1191, https://github.com/fmtlib/fmt/issues/1197, https://github.com/fmtlib/fmt/issues/1200, https://github.com/fmtlib/fmt/issues/1203, https://github.com/fmtlib/fmt/issues/1205, https://github.com/fmtlib/fmt/pull/1206, https://github.com/fmtlib/fmt/issues/1213, https://github.com/fmtlib/fmt/issues/1214, https://github.com/fmtlib/fmt/pull/1217, https://github.com/fmtlib/fmt/issues/1228, https://github.com/fmtlib/fmt/pull/1230, https://github.com/fmtlib/fmt/issues/1232, https://github.com/fmtlib/fmt/pull/1235, https://github.com/fmtlib/fmt/pull/1236, https://github.com/fmtlib/fmt/issues/1240). Thanks @DanielaE, @mwinterb, @eliaskosunen, @morinmorin, @ricco19, @waywardmonkeys, @chronoxor, @remyabel, @pauldreik, @gsjaardema, @rcane, @mocabe, @denchat, @cjdb, @HazardyKnusperkeks, @vedranmiletic, @jackoalan, @DaanDeMeyer and @starkmapper.
5.3.0 - 2018-12-28
-
Introduced experimental chrono formatting support:
#include <fmt/chrono.h> int main() { using namespace std::literals::chrono_literals; fmt::print("Default format: {} {}\n", 42s, 100ms); fmt::print("strftime-like format: {:%H:%M:%S}\n", 3h + 15min + 30s); }
prints:
Default format: 42s 100ms strftime-like format: 03:15:30
-
Added experimental support for emphasis (bold, italic, underline, strikethrough), colored output to a file stream, and improved colored formatting API (https://github.com/fmtlib/fmt/pull/961, https://github.com/fmtlib/fmt/pull/967, https://github.com/fmtlib/fmt/pull/973):
#include <fmt/color.h> int main() { print(fg(fmt::color::crimson) | fmt::emphasis::bold, "Hello, {}!\n", "world"); print(fg(fmt::color::floral_white) | bg(fmt::color::slate_gray) | fmt::emphasis::underline, "Hello, {}!\n", "мир"); print(fg(fmt::color::steel_blue) | fmt::emphasis::italic, "Hello, {}!\n", "世界"); }
prints the following on modern terminals with RGB color support:
Thanks @Rakete1111.
-
Added support for 4-bit terminal colors (https://github.com/fmtlib/fmt/issues/968, https://github.com/fmtlib/fmt/pull/974)
#include <fmt/color.h> int main() { print(fg(fmt::terminal_color::red), "stop\n"); }
Note that these colors vary by terminal:
Thanks @Rakete1111.
-
Parameterized formatting functions on the type of the format string (https://github.com/fmtlib/fmt/issues/880, https://github.com/fmtlib/fmt/pull/881, https://github.com/fmtlib/fmt/pull/883, https://github.com/fmtlib/fmt/pull/885, https://github.com/fmtlib/fmt/pull/897, https://github.com/fmtlib/fmt/issues/920). Any object of type
S
that has an overloadedto_string_view(const S&)
returningfmt::string_view
can be used as a format string:namespace my_ns { inline string_view to_string_view(const my_string& s) { return {s.data(), s.length()}; } } std::string message = fmt::format(my_string("The answer is {}."), 42);
Thanks @DanielaE.
-
Made
std::string_view
work as a format string (https://github.com/fmtlib/fmt/pull/898):auto message = fmt::format(std::string_view("The answer is {}."), 42);
Thanks @DanielaE.
-
Added wide string support to compile-time format string checks (https://github.com/fmtlib/fmt/pull/924):
print(fmt(L"{:f}"), 42); // compile-time error: invalid type specifier
Thanks @XZiar.
-
Made colored print functions work with wide strings (https://github.com/fmtlib/fmt/pull/867):
#include <fmt/color.h> int main() { print(fg(fmt::color::red), L"{}\n", 42); }
Thanks @DanielaE.
-
Introduced experimental Unicode support (https://github.com/fmtlib/fmt/issues/628, https://github.com/fmtlib/fmt/pull/891):
using namespace fmt::literals; auto s = fmt::format("{:*^5}"_u, "🤡"_u); // s == "**🤡**"_u
-
Improved locale support:
#include <fmt/locale.h> struct numpunct : std::numpunct<char> { protected: char do_thousands_sep() const override { return '~'; } }; std::locale loc; auto s = fmt::format(std::locale(loc, new numpunct()), "{:n}", 1234567); // s == "1~234~567"
-
Constrained formatting functions on proper iterator types (https://github.com/fmtlib/fmt/pull/921). Thanks @DanielaE.
-
Added
make_printf_args
andmake_wprintf_args
functions (https://github.com/fmtlib/fmt/pull/934). Thanks @tnovotny. -
Deprecated
fmt::visit
,parse_context
, andwparse_context
. Usefmt::visit_format_arg
,format_parse_context
, andwformat_parse_context
instead. -
Removed undocumented
basic_fixed_buffer
which has been superseded by the iterator-based API (https://github.com/fmtlib/fmt/issues/873, https://github.com/fmtlib/fmt/pull/902). Thanks @superfunc. -
Disallowed repeated leading zeros in an argument ID:
fmt::print("{000}", 42); // error
-
Reintroduced support for gcc 4.4.
-
Fixed compilation on platforms with exotic
double
(https://github.com/fmtlib/fmt/issues/878). -
Improved documentation (https://github.com/fmtlib/fmt/issues/164, https://github.com/fmtlib/fmt/issues/877, https://github.com/fmtlib/fmt/pull/901, https://github.com/fmtlib/fmt/pull/906, https://github.com/fmtlib/fmt/pull/979). Thanks @kookjr, @DarkDimius and @HecticSerenity.
-
Added pkgconfig support which makes it easier to consume the library from meson and other build systems (https://github.com/fmtlib/fmt/pull/916). Thanks @colemickens.
-
Various build improvements (https://github.com/fmtlib/fmt/pull/909, https://github.com/fmtlib/fmt/pull/926, https://github.com/fmtlib/fmt/pull/937, https://github.com/fmtlib/fmt/pull/953, https://github.com/fmtlib/fmt/pull/959). Thanks @tchaikov, @luncliff, @AndreasSchoenle, @hotwatermorning and @Zefz.
-
Improved
string_view
construction performance (https://github.com/fmtlib/fmt/pull/914). Thanks @gabime. -
Fixed non-matching char types (https://github.com/fmtlib/fmt/pull/895). Thanks @DanielaE.
-
Fixed
format_to_n
withstd::back_insert_iterator
(https://github.com/fmtlib/fmt/pull/913). Thanks @DanielaE. -
Fixed locale-dependent formatting (https://github.com/fmtlib/fmt/issues/905).
-
Fixed various compiler warnings and errors (https://github.com/fmtlib/fmt/pull/882, https://github.com/fmtlib/fmt/pull/886, https://github.com/fmtlib/fmt/pull/933, https://github.com/fmtlib/fmt/pull/941, https://github.com/fmtlib/fmt/issues/931, https://github.com/fmtlib/fmt/pull/943, https://github.com/fmtlib/fmt/pull/954, https://github.com/fmtlib/fmt/pull/956, https://github.com/fmtlib/fmt/pull/962, https://github.com/fmtlib/fmt/issues/965, https://github.com/fmtlib/fmt/issues/977, https://github.com/fmtlib/fmt/pull/983, https://github.com/fmtlib/fmt/pull/989). Thanks @Luthaf, @stevenhoving, @christinaa, @lgritz, @DanielaE, @0x8000-0000 and @liuping1997.
5.2.1 - 2018-09-21
- Fixed
visit
lookup issues on gcc 7 & 8 (https://github.com/fmtlib/fmt/pull/870). Thanks @medithe. - Fixed linkage errors on older gcc.
- Prevented
fmt/range.h
from specializingfmt::basic_string_view
(https://github.com/fmtlib/fmt/issues/865, https://github.com/fmtlib/fmt/pull/868). Thanks @hhggit. - Improved error message when formatting unknown types (https://github.com/fmtlib/fmt/pull/872). Thanks @foonathan.
- Disabled templated user-defined literals when compiled under nvcc (https://github.com/fmtlib/fmt/pull/875). Thanks @CandyGumdrop.
- Fixed
format_to
formatting towmemory_buffer
(https://github.com/fmtlib/fmt/issues/874).
5.2.0 - 2018-09-13
-
Optimized format string parsing and argument processing which resulted in up to 5x speed up on long format strings and significant performance boost on various benchmarks. For example, version 5.2 is 2.22x faster than 5.1 on decimal integer formatting with
format_to
(macOS, clang-902.0.39.2):Method Time, s Speedup fmt::format 5.1 0.58 fmt::format 5.2 0.35 1.66x fmt::format_to 5.1 0.51 fmt::format_to 5.2 0.23 2.22x sprintf 0.71 std::to_string 1.01 std::stringstream 1.73 -
Changed the
fmt
macro from opt-out to opt-in to prevent name collisions. To enable it define theFMT_STRING_ALIAS
macro to 1 before includingfmt/format.h
:#define FMT_STRING_ALIAS 1 #include <fmt/format.h> std::string answer = format(fmt("{}"), 42);
-
Added compile-time format string checks to
format_to
overload that takesfmt::memory_buffer
(https://github.com/fmtlib/fmt/issues/783):fmt::memory_buffer buf; // Compile-time error: invalid type specifier. fmt::format_to(buf, fmt("{:d}"), "foo");
-
Moved experimental color support to
fmt/color.h
and enabled the new API by default. The old API can be enabled by defining theFMT_DEPRECATED_COLORS
macro. -
Added formatting support for types explicitly convertible to
fmt::string_view
:struct foo { explicit operator fmt::string_view() const { return "foo"; } }; auto s = format("{}", foo());
In particular, this makes formatting function work with
folly::StringPiece
. -
Implemented preliminary support for
char*_t
by replacing theformat
function overloads with a single function template parameterized on the string type. -
Added support for dynamic argument lists (https://github.com/fmtlib/fmt/issues/814, https://github.com/fmtlib/fmt/pull/819). Thanks @MikePopoloski.
-
Reduced executable size overhead for embedded targets using newlib nano by making locale dependency optional (https://github.com/fmtlib/fmt/pull/839). Thanks @teajay-fr.
-
Keep
noexcept
specifier when exceptions are disabled (https://github.com/fmtlib/fmt/issues/801, https://github.com/fmtlib/fmt/pull/810). Thanks @qis. -
Fixed formatting of user-defined types providing
operator<<
withformat_to_n
(https://github.com/fmtlib/fmt/pull/806). Thanks @mkurdej. -
Fixed dynamic linkage of new symbols (https://github.com/fmtlib/fmt/issues/808).
-
Fixed global initialization issue (https://github.com/fmtlib/fmt/issues/807):
// This works on compilers with constexpr support. static const std::string answer = fmt::format("{}", 42);
-
Fixed various compiler warnings and errors (https://github.com/fmtlib/fmt/pull/804, https://github.com/fmtlib/fmt/issues/809, https://github.com/fmtlib/fmt/pull/811, https://github.com/fmtlib/fmt/issues/822, https://github.com/fmtlib/fmt/pull/827, https://github.com/fmtlib/fmt/issues/830, https://github.com/fmtlib/fmt/pull/838, https://github.com/fmtlib/fmt/issues/843, https://github.com/fmtlib/fmt/pull/844, https://github.com/fmtlib/fmt/issues/851, https://github.com/fmtlib/fmt/pull/852, https://github.com/fmtlib/fmt/pull/854). Thanks @henryiii, @medithe, and @eliasdaler.
5.1.0 - 2018-07-05
-
Added experimental support for RGB color output enabled with the
FMT_EXTENDED_COLORS
macro:#define FMT_EXTENDED_COLORS #define FMT_HEADER_ONLY // or compile fmt with FMT_EXTENDED_COLORS defined #include <fmt/format.h> fmt::print(fmt::color::steel_blue, "Some beautiful text");
The old API (the
print_colored
andvprint_colored
functions and thecolor
enum) is now deprecated. (https://github.com/fmtlib/fmt/issues/762 https://github.com/fmtlib/fmt/pull/767). thanks @Remotion. -
Added quotes to strings in ranges and tuples (https://github.com/fmtlib/fmt/pull/766). Thanks @Remotion.
-
Made
format_to
work withbasic_memory_buffer
(https://github.com/fmtlib/fmt/issues/776). -
Added
vformat_to_n
andwchar_t
overload offormat_to_n
(https://github.com/fmtlib/fmt/issues/764, https://github.com/fmtlib/fmt/issues/769). -
Made
is_range
andis_tuple_like
part of public (experimental) API to allow specialization for user-defined types (https://github.com/fmtlib/fmt/issues/751, https://github.com/fmtlib/fmt/pull/759). Thanks @drrlvn. -
Added more compilers to continuous integration and increased
FMT_PEDANTIC
warning levels (https://github.com/fmtlib/fmt/pull/736). Thanks @eliaskosunen. -
Fixed compilation with MSVC 2013.
-
Fixed handling of user-defined types in
format_to
(https://github.com/fmtlib/fmt/issues/793). -
Forced linking of inline
vformat
functions into the library (https://github.com/fmtlib/fmt/issues/795). -
Fixed incorrect call to on_align in
'{:}='
(https://github.com/fmtlib/fmt/issues/750). -
Fixed floating-point formatting to a non-back_insert_iterator with sign & numeric alignment specified (https://github.com/fmtlib/fmt/issues/756).
-
Fixed formatting to an array with
format_to_n
(https://github.com/fmtlib/fmt/issues/778). -
Fixed formatting of more than 15 named arguments (https://github.com/fmtlib/fmt/issues/754).
-
Fixed handling of compile-time strings when including
fmt/ostream.h
. (https://github.com/fmtlib/fmt/issues/768). -
Fixed various compiler warnings and errors (https://github.com/fmtlib/fmt/issues/742, https://github.com/fmtlib/fmt/issues/748, https://github.com/fmtlib/fmt/issues/752, https://github.com/fmtlib/fmt/issues/770, https://github.com/fmtlib/fmt/pull/775, https://github.com/fmtlib/fmt/issues/779, https://github.com/fmtlib/fmt/pull/780, https://github.com/fmtlib/fmt/pull/790, https://github.com/fmtlib/fmt/pull/792, https://github.com/fmtlib/fmt/pull/800). Thanks @Remotion, @gabime, @foonathan, @Dark-Passenger and @0x8000-0000.
5.0.0 - 2018-05-21
-
Added a requirement for partial C++11 support, most importantly variadic templates and type traits, and dropped
FMT_VARIADIC_*
emulation macros. Variadic templates are available since GCC 4.4, Clang 2.9 and MSVC 18.0 (2013). For older compilers use {fmt} version 4.x which continues to be maintained and works with C++98 compilers. -
Renamed symbols to follow standard C++ naming conventions and proposed a subset of the library for standardization in P0645R2 Text Formatting.
-
Implemented
constexpr
parsing of format strings and compile-time format string checks. For example#include <fmt/format.h> std::string s = format(fmt("{:d}"), "foo");
gives a compile-time error because
d
is an invalid specifier for strings (godbolt):... <source>:4:19: note: in instantiation of function template specialization 'fmt::v5::format<S, char [4]>' requested here std::string s = format(fmt("{:d}"), "foo"); ^ format.h:1337:13: note: non-constexpr function 'on_error' cannot be used in a constant expression handler.on_error("invalid type specifier");
Compile-time checks require relaxed
constexpr
(C++14 feature) support. If the latter is not available, checks will be performed at runtime. -
Separated format string parsing and formatting in the extension API to enable compile-time format string processing. For example
struct Answer {}; namespace fmt { template <> struct formatter<Answer> { constexpr auto parse(parse_context& ctx) { auto it = ctx.begin(); spec = *it; if (spec != 'd' && spec != 's') throw format_error("invalid specifier"); return ++it; } template <typename FormatContext> auto format(Answer, FormatContext& ctx) { return spec == 's' ? format_to(ctx.begin(), "{}", "fourty-two") : format_to(ctx.begin(), "{}", 42); } char spec = 0; }; } std::string s = format(fmt("{:x}"), Answer());
gives a compile-time error due to invalid format specifier (godbolt):
... <source>:12:45: error: expression '<throw-expression>' is not a constant expression throw format_error("invalid specifier");
-
Added iterator support:
#include <vector> #include <fmt/format.h> std::vector<char> out; fmt::format_to(std::back_inserter(out), "{}", 42);
-
Added the format_to_n function that restricts the output to the specified number of characters (https://github.com/fmtlib/fmt/issues/298):
char out[4]; fmt::format_to_n(out, sizeof(out), "{}", 12345); // out == "1234" (without terminating '\0')
-
Added the formatted_size function for computing the output size:
#include <fmt/format.h> auto size = fmt::formatted_size("{}", 12345); // size == 5
-
Improved compile times by reducing dependencies on standard headers and providing a lightweight core API:
#include <fmt/core.h> fmt::print("The answer is {}.", 42);
-
Added the make_format_args function for capturing formatting arguments:
// Prints formatted error message. void vreport_error(const char *format, fmt::format_args args) { fmt::print("Error: "); fmt::vprint(format, args); } template <typename... Args> void report_error(const char *format, const Args & ... args) { vreport_error(format, fmt::make_format_args(args...)); }
-
Added the
make_printf_args
function for capturingprintf
arguments (https://github.com/fmtlib/fmt/issues/687, https://github.com/fmtlib/fmt/pull/694). Thanks @Kronuz. -
Added prefix
v
to non-variadic functions takingformat_args
to distinguish them from variadic ones:std::string vformat(string_view format_str, format_args args); template <typename... Args> std::string format(string_view format_str, const Args & ... args);
-
Added experimental support for formatting ranges, containers and tuple-like types in
fmt/ranges.h
(https://github.com/fmtlib/fmt/pull/735):#include <fmt/ranges.h> std::vector<int> v = {1, 2, 3}; fmt::print("{}", v); // prints {1, 2, 3}
Thanks @Remotion.
-
Implemented
wchar_t
date and time formatting (https://github.com/fmtlib/fmt/pull/712):#include <fmt/time.h> std::time_t t = std::time(nullptr); auto s = fmt::format(L"The date is {:%Y-%m-%d}.", *std::localtime(&t));
Thanks @DanielaE.
-
Provided more wide string overloads (https://github.com/fmtlib/fmt/pull/724). Thanks @DanielaE.
-
Switched from a custom null-terminated string view class to
string_view
in the format API and providedfmt::string_view
which implements a subset ofstd::string_view
API for pre-C++17 systems. -
Added support for
std::experimental::string_view
(https://github.com/fmtlib/fmt/pull/607):#include <fmt/core.h> #include <experimental/string_view> fmt::print("{}", std::experimental::string_view("foo"));
Thanks @virgiliofornazin.
-
Allowed mixing named and automatic arguments:
fmt::format("{} {two}", 1, fmt::arg("two", 2));
-
Removed the write API in favor of the format API with compile-time handling of format strings.
-
Disallowed formatting of multibyte strings into a wide character target (https://github.com/fmtlib/fmt/pull/606).
-
Improved documentation (https://github.com/fmtlib/fmt/pull/515, https://github.com/fmtlib/fmt/issues/614, https://github.com/fmtlib/fmt/pull/617, https://github.com/fmtlib/fmt/pull/661, https://github.com/fmtlib/fmt/pull/680). Thanks @ibell, @mihaitodor and @johnthagen.
-
Implemented more efficient handling of large number of format arguments.
-
Introduced an inline namespace for symbol versioning.
-
Added debug postfix
d
to thefmt
library name (https://github.com/fmtlib/fmt/issues/636). -
Removed unnecessary
fmt/
prefix in includes (https://github.com/fmtlib/fmt/pull/397). Thanks @chronoxor. -
Moved
fmt/*.h
toinclude/fmt/*.h
to prevent irrelevant files and directories appearing on the include search paths when fmt is used as a subproject and moved source files to thesrc
directory. -
Added qmake project file
support/fmt.pro
(https://github.com/fmtlib/fmt/pull/641). Thanks @cowo78. -
Added Gradle build file
support/build.gradle
(https://github.com/fmtlib/fmt/pull/649). Thanks @luncliff. -
Removed
FMT_CPPFORMAT
CMake option. -
Fixed a name conflict with the macro
CHAR_WIDTH
in glibc (https://github.com/fmtlib/fmt/pull/616). Thanks @aroig. -
Fixed handling of nested braces in
fmt::join
(https://github.com/fmtlib/fmt/issues/638). -
Added
SOURCELINK_SUFFIX
for compatibility with Sphinx 1.5 (https://github.com/fmtlib/fmt/pull/497). Thanks @ginggs. -
Added a missing
inline
in the header-only mode (https://github.com/fmtlib/fmt/pull/626). Thanks @aroig. -
Fixed various compiler warnings (https://github.com/fmtlib/fmt/pull/640, https://github.com/fmtlib/fmt/pull/656, https://github.com/fmtlib/fmt/pull/679, https://github.com/fmtlib/fmt/pull/681, https://github.com/fmtlib/fmt/pull/705, https://github.com/fmtlib/fmt/issues/715, https://github.com/fmtlib/fmt/pull/717, https://github.com/fmtlib/fmt/pull/720, https://github.com/fmtlib/fmt/pull/723, https://github.com/fmtlib/fmt/pull/726, https://github.com/fmtlib/fmt/pull/730, https://github.com/fmtlib/fmt/pull/739). Thanks @peterbell10, @LarsGullik, @foonathan, @eliaskosunen, @christianparpart, @DanielaE and @mwinterb.
-
Worked around an MSVC bug and fixed several warnings (https://github.com/fmtlib/fmt/pull/653). Thanks @alabuzhev.
-
Worked around GCC bug 67371 (https://github.com/fmtlib/fmt/issues/682).
-
Fixed compilation with
-fno-exceptions
(https://github.com/fmtlib/fmt/pull/655). Thanks @chenxiaolong. -
Made
constexpr remove_prefix
gcc version check tighter (https://github.com/fmtlib/fmt/issues/648). -
Renamed internal type enum constants to prevent collision with poorly written C libraries (https://github.com/fmtlib/fmt/issues/644).
-
Added detection of
wostream operator<<
(https://github.com/fmtlib/fmt/issues/650). -
Fixed compilation on OpenBSD (https://github.com/fmtlib/fmt/pull/660). Thanks @hubslave.
-
Fixed compilation on FreeBSD 12 (https://github.com/fmtlib/fmt/pull/732). Thanks @dankm.
-
Fixed compilation when there is a mismatch between
-std
options between the library and user code (https://github.com/fmtlib/fmt/issues/664). -
Fixed compilation with GCC 7 and
-std=c++11
(https://github.com/fmtlib/fmt/issues/734). -
Improved generated binary code on GCC 7 and older (https://github.com/fmtlib/fmt/issues/668).
-
Fixed handling of numeric alignment with no width (https://github.com/fmtlib/fmt/issues/675).
-
Fixed handling of empty strings in UTF8/16 converters (https://github.com/fmtlib/fmt/pull/676). Thanks @vgalka-sl.
-
Fixed formatting of an empty
string_view
(https://github.com/fmtlib/fmt/issues/689). -
Fixed detection of
string_view
on libc++ (https://github.com/fmtlib/fmt/issues/686). -
Fixed DLL issues (https://github.com/fmtlib/fmt/pull/696). Thanks @sebkoenig.
-
Fixed compile checks for mixing narrow and wide strings (https://github.com/fmtlib/fmt/issues/690).
-
Disabled unsafe implicit conversion to
std::string
(https://github.com/fmtlib/fmt/issues/729). -
Fixed handling of reused format specs (as in
fmt::join
) for pointers (https://github.com/fmtlib/fmt/pull/725). Thanks @mwinterb. -
Fixed installation of
fmt/ranges.h
(https://github.com/fmtlib/fmt/pull/738). Thanks @sv1990.
4.1.0 - 2017-12-20
- Added
fmt::to_wstring()
in addition tofmt::to_string()
(https://github.com/fmtlib/fmt/pull/559). Thanks @alabuzhev. - Added support for C++17
std::string_view
(https://github.com/fmtlib/fmt/pull/571 and https://github.com/fmtlib/fmt/pull/578). Thanks @thelostt and @mwinterb. - Enabled stream exceptions to catch errors (https://github.com/fmtlib/fmt/issues/581). Thanks @crusader-mike.
- Allowed formatting of class hierarchies with
fmt::format_arg()
(https://github.com/fmtlib/fmt/pull/547). Thanks @rollbear. - Removed limitations on character types (https://github.com/fmtlib/fmt/pull/563). Thanks @Yelnats321.
- Conditionally enabled use of
std::allocator_traits
(https://github.com/fmtlib/fmt/pull/583). Thanks @mwinterb. - Added support for
const
variadic member function emulation withFMT_VARIADIC_CONST
(https://github.com/fmtlib/fmt/pull/591). Thanks @ludekvodicka. - Various bugfixes: bad overflow check, unsupported implicit type conversion when determining formatting function, test segfaults (https://github.com/fmtlib/fmt/issues/551), ill-formed macros (https://github.com/fmtlib/fmt/pull/542) and ambiguous overloads (https://github.com/fmtlib/fmt/issues/580). Thanks @xylosper.
- Prevented warnings on MSVC
(https://github.com/fmtlib/fmt/pull/605,
https://github.com/fmtlib/fmt/pull/602, and
https://github.com/fmtlib/fmt/pull/545), clang
(https://github.com/fmtlib/fmt/pull/582), GCC
(https://github.com/fmtlib/fmt/issues/573), various
conversion warnings (https://github.com/fmtlib/fmt/pull/609,
https://github.com/fmtlib/fmt/pull/567,
https://github.com/fmtlib/fmt/pull/553 and
https://github.com/fmtlib/fmt/pull/553), and added
override
and[[noreturn]]
(https://github.com/fmtlib/fmt/pull/549 and https://github.com/fmtlib/fmt/issues/555). Thanks @alabuzhev, @virgiliofornazin, @alexanderbock, @yumetodo, @VaderY, @jpcima, @thelostt and @Manu343726. - Improved CMake: Used
GNUInstallDirs
to set installation location (https://github.com/fmtlib/fmt/pull/610) and fixed warnings (https://github.com/fmtlib/fmt/pull/536 and https://github.com/fmtlib/fmt/pull/556). Thanks @mikecrowe, @evgen231 and @henryiii.
4.0.0 - 2017-06-27
-
Removed old compatibility headers
cppformat/*.h
and CMake options (https://github.com/fmtlib/fmt/pull/527). Thanks @maddinat0r. -
Added
string.h
containingfmt::to_string()
as alternative tostd::to_string()
as well as other string writer functionality (https://github.com/fmtlib/fmt/issues/326 and https://github.com/fmtlib/fmt/pull/441):#include "fmt/string.h" std::string answer = fmt::to_string(42);
Thanks @glebov-andrey.
-
Moved
fmt::printf()
to newprintf.h
header and allowed%s
as generic specifier (https://github.com/fmtlib/fmt/pull/453), made%.f
more conformant to regularprintf()
(https://github.com/fmtlib/fmt/pull/490), added custom writer support (https://github.com/fmtlib/fmt/issues/476) and implemented missing custom argument formatting (https://github.com/fmtlib/fmt/pull/339 and https://github.com/fmtlib/fmt/pull/340):#include "fmt/printf.h" // %s format specifier can be used with any argument type. fmt::printf("%s", 42);
Thanks @mojoBrendan, @manylegged and @spacemoose. See also https://github.com/fmtlib/fmt/issues/360, https://github.com/fmtlib/fmt/issues/335 and https://github.com/fmtlib/fmt/issues/331.
-
Added
container.h
containing aBasicContainerWriter
to write to containers likestd::vector
(https://github.com/fmtlib/fmt/pull/450). Thanks @polyvertex. -
Added
fmt::join()
function that takes a range and formats its elements separated by a given string (https://github.com/fmtlib/fmt/pull/466):#include "fmt/format.h" std::vector<double> v = {1.2, 3.4, 5.6}; // Prints "(+01.20, +03.40, +05.60)". fmt::print("({:+06.2f})", fmt::join(v.begin(), v.end(), ", "));
Thanks @olivier80.
-
Added support for custom formatting specifications to simplify customization of built-in formatting (https://github.com/fmtlib/fmt/pull/444). Thanks @polyvertex. See also https://github.com/fmtlib/fmt/issues/439.
-
Added
fmt::format_system_error()
for error code formatting (https://github.com/fmtlib/fmt/issues/323 and https://github.com/fmtlib/fmt/pull/526). Thanks @maddinat0r. -
Added thread-safe
fmt::localtime()
andfmt::gmtime()
as replacement for the standard version totime.h
(https://github.com/fmtlib/fmt/pull/396). Thanks @codicodi. -
Internal improvements to
NamedArg
andArgLists
(https://github.com/fmtlib/fmt/pull/389 and https://github.com/fmtlib/fmt/pull/390). Thanks @chronoxor. -
Fixed crash due to bug in
FormatBuf
(https://github.com/fmtlib/fmt/pull/493). Thanks @effzeh. See also https://github.com/fmtlib/fmt/issues/480 and https://github.com/fmtlib/fmt/issues/491. -
Fixed handling of wide strings in
fmt::StringWriter
. -
Improved compiler error messages (https://github.com/fmtlib/fmt/issues/357).
-
Fixed various warnings and issues with various compilers (https://github.com/fmtlib/fmt/pull/494, https://github.com/fmtlib/fmt/pull/499, https://github.com/fmtlib/fmt/pull/483, https://github.com/fmtlib/fmt/pull/485, https://github.com/fmtlib/fmt/pull/482, https://github.com/fmtlib/fmt/pull/475, https://github.com/fmtlib/fmt/pull/473 and https://github.com/fmtlib/fmt/pull/414). Thanks @chronoxor, @zhaohuaxishi, @pkestene, @dschmidt and @0x414c.
-
Improved CMake: targets are now namespaced (https://github.com/fmtlib/fmt/pull/511 and https://github.com/fmtlib/fmt/pull/513), supported header-only
printf.h
(https://github.com/fmtlib/fmt/pull/354), fixed issue with minimal supported library subset (https://github.com/fmtlib/fmt/issues/418, https://github.com/fmtlib/fmt/pull/419 and https://github.com/fmtlib/fmt/pull/420). Thanks @bjoernthiel, @niosHD, @LogicalKnight and @alabuzhev. -
Improved documentation (https://github.com/fmtlib/fmt/pull/393). Thanks @pwm1234.
3.0.2 - 2017-06-14
- Added
FMT_VERSION
macro (https://github.com/fmtlib/fmt/issues/411). - Used
FMT_NULL
instead of literal0
(https://github.com/fmtlib/fmt/pull/409). Thanks @alabuzhev. - Added extern templates for
format_float
(https://github.com/fmtlib/fmt/issues/413). - Fixed implicit conversion issue (https://github.com/fmtlib/fmt/issues/507).
- Fixed signbit detection (https://github.com/fmtlib/fmt/issues/423).
- Fixed naming collision (https://github.com/fmtlib/fmt/issues/425).
- Fixed missing intrinsic for C++/CLI (https://github.com/fmtlib/fmt/pull/457). Thanks @calumr.
- Fixed Android detection (https://github.com/fmtlib/fmt/pull/458). Thanks @Gachapen.
- Use lean
windows.h
if not in header-only mode (https://github.com/fmtlib/fmt/pull/503). Thanks @Quentin01. - Fixed issue with CMake exporting C++11 flag (https://github.com/fmtlib/fmt/pull/455). Thanks @EricWF.
- Fixed issue with nvcc and MSVC compiler bug and MinGW (https://github.com/fmtlib/fmt/issues/505).
- Fixed DLL issues (https://github.com/fmtlib/fmt/pull/469 and https://github.com/fmtlib/fmt/pull/502). Thanks @richardeakin and @AndreasSchoenle.
- Fixed test compilation under FreeBSD (https://github.com/fmtlib/fmt/issues/433).
- Fixed various warnings (https://github.com/fmtlib/fmt/pull/403, https://github.com/fmtlib/fmt/pull/410 and https://github.com/fmtlib/fmt/pull/510). Thanks @Lecetem, @chenhayat and @trozen.
- Worked around a broken
__builtin_clz
in clang with MS codegen (https://github.com/fmtlib/fmt/issues/519). - Removed redundant include (https://github.com/fmtlib/fmt/issues/479).
- Fixed documentation issues.
3.0.1 - 2016-11-01
- Fixed handling of thousands separator (https://github.com/fmtlib/fmt/issues/353).
- Fixed handling of
unsigned char
strings (https://github.com/fmtlib/fmt/issues/373). - Corrected buffer growth when formatting time (https://github.com/fmtlib/fmt/issues/367).
- Removed warnings under MSVC and clang (https://github.com/fmtlib/fmt/issues/318, https://github.com/fmtlib/fmt/issues/250, also merged https://github.com/fmtlib/fmt/pull/385 and https://github.com/fmtlib/fmt/pull/361). Thanks @jcelerier and @nmoehrle.
- Fixed compilation issues under Android (https://github.com/fmtlib/fmt/pull/327, https://github.com/fmtlib/fmt/issues/345 and https://github.com/fmtlib/fmt/pull/381), FreeBSD (https://github.com/fmtlib/fmt/pull/358), Cygwin (https://github.com/fmtlib/fmt/issues/388), MinGW (https://github.com/fmtlib/fmt/issues/355) as well as other issues (https://github.com/fmtlib/fmt/issues/350, https://github.com/fmtlib/fmt/issues/355, https://github.com/fmtlib/fmt/pull/348, https://github.com/fmtlib/fmt/pull/402, https://github.com/fmtlib/fmt/pull/405). Thanks @dpantele, @hghwng, @arvedarved, @LogicalKnight and @JanHellwig.
- Fixed some documentation issues and extended specification (https://github.com/fmtlib/fmt/issues/320, https://github.com/fmtlib/fmt/pull/333, https://github.com/fmtlib/fmt/issues/347, https://github.com/fmtlib/fmt/pull/362). Thanks @smellman.
3.0.0 - 2016-05-07
-
The project has been renamed from C++ Format (cppformat) to fmt for consistency with the used namespace and macro prefix (https://github.com/fmtlib/fmt/issues/307). Library headers are now located in the
fmt
directory:#include "fmt/format.h"
Including
format.h
from thecppformat
directory is deprecated but works via a proxy header which will be removed in the next major version.The documentation is now available at https://fmt.dev.
-
Added support for strftime-like date and time formatting (https://github.com/fmtlib/fmt/issues/283):
#include "fmt/time.h" std::time_t t = std::time(nullptr); // Prints "The date is 2016-04-29." (with the current date) fmt::print("The date is {:%Y-%m-%d}.", *std::localtime(&t));
-
std::ostream
support including formatting of user-defined types that provide overloadedoperator<<
has been moved tofmt/ostream.h
:#include "fmt/ostream.h" class Date { int year_, month_, day_; public: Date(int year, int month, int day) : year_(year), month_(month), day_(day) {} friend std::ostream &operator<<(std::ostream &os, const Date &d) { return os << d.year_ << '-' << d.month_ << '-' << d.day_; } }; std::string s = fmt::format("The date is {}", Date(2012, 12, 9)); // s == "The date is 2012-12-9"
-
Added support for custom argument formatters (https://github.com/fmtlib/fmt/issues/235).
-
Added support for locale-specific integer formatting with the
n
specifier (https://github.com/fmtlib/fmt/issues/305):std::setlocale(LC_ALL, "en_US.utf8"); fmt::print("cppformat: {:n}\n", 1234567); // prints 1,234,567
-
Sign is now preserved when formatting an integer with an incorrect
printf
format specifier (https://github.com/fmtlib/fmt/issues/265):fmt::printf("%lld", -42); // prints -42
Note that it would be an undefined behavior in
std::printf
. -
Length modifiers such as
ll
are now optional in printf formatting functions and the correct type is determined automatically (https://github.com/fmtlib/fmt/issues/255):fmt::printf("%d", std::numeric_limits<long long>::max());
Note that it would be an undefined behavior in
std::printf
. -
Added initial support for custom formatters (https://github.com/fmtlib/fmt/issues/231).
-
Fixed detection of user-defined literal support on Intel C++ compiler (https://github.com/fmtlib/fmt/issues/311, https://github.com/fmtlib/fmt/pull/312). Thanks @dean0x7d and @speth.
-
Reduced compile time (https://github.com/fmtlib/fmt/pull/243, https://github.com/fmtlib/fmt/pull/249, https://github.com/fmtlib/fmt/issues/317):
Thanks @dean0x7d.
-
Compile test fixes (https://github.com/fmtlib/fmt/pull/313). Thanks @dean0x7d.
-
Documentation fixes (https://github.com/fmtlib/fmt/pull/239, https://github.com/fmtlib/fmt/issues/248, https://github.com/fmtlib/fmt/issues/252, https://github.com/fmtlib/fmt/pull/258, https://github.com/fmtlib/fmt/issues/260, https://github.com/fmtlib/fmt/issues/301, https://github.com/fmtlib/fmt/pull/309). Thanks @ReadmeCritic @Gachapen and @jwilk.
-
Fixed compiler and sanitizer warnings (https://github.com/fmtlib/fmt/issues/244, https://github.com/fmtlib/fmt/pull/256, https://github.com/fmtlib/fmt/pull/259, https://github.com/fmtlib/fmt/issues/263, https://github.com/fmtlib/fmt/issues/274, https://github.com/fmtlib/fmt/pull/277, https://github.com/fmtlib/fmt/pull/286, https://github.com/fmtlib/fmt/issues/291, https://github.com/fmtlib/fmt/issues/296, https://github.com/fmtlib/fmt/issues/308). Thanks @mwinterb, @pweiskircher and @Naios.
-
Improved compatibility with Windows Store apps (https://github.com/fmtlib/fmt/issues/280, https://github.com/fmtlib/fmt/pull/285) Thanks @mwinterb.
-
Added tests of compatibility with older C++ standards (https://github.com/fmtlib/fmt/pull/273). Thanks @niosHD.
-
Fixed Android build (https://github.com/fmtlib/fmt/pull/271). Thanks @newnon.
-
Changed
ArgMap
to be backed by a vector instead of a map. (https://github.com/fmtlib/fmt/issues/261, https://github.com/fmtlib/fmt/pull/262). Thanks @mwinterb. -
Added
fprintf
overload that writes to astd::ostream
(https://github.com/fmtlib/fmt/pull/251). Thanks @nickhutchinson. -
Export symbols when building a Windows DLL (https://github.com/fmtlib/fmt/pull/245). Thanks @macdems.
-
Fixed compilation on Cygwin (https://github.com/fmtlib/fmt/issues/304).
-
Implemented a workaround for a bug in Apple LLVM version 4.2 of clang (https://github.com/fmtlib/fmt/issues/276).
-
Implemented a workaround for Google Test bug https://github.com/google/googletest/issues/705 on gcc 6 (https://github.com/fmtlib/fmt/issues/268). Thanks @octoploid.
-
Removed Biicode support because the latter has been discontinued.
2.1.1 - 2016-04-11
- The install location for generated CMake files is now configurable
via the
FMT_CMAKE_DIR
CMake variable (https://github.com/fmtlib/fmt/pull/299). Thanks @niosHD. - Documentation fixes (https://github.com/fmtlib/fmt/issues/252).
2.1.0 - 2016-03-21
-
Project layout and build system improvements (https://github.com/fmtlib/fmt/pull/267):
- The code have been moved to the
cppformat
directory. Includingformat.h
from the top-level directory is deprecated but works via a proxy header which will be removed in the next major version. - C++ Format CMake targets now have proper interface definitions.
- Installed version of the library now supports the header-only configuration.
- Targets
doc
,install
, andtest
are now disabled if C++ Format is included as a CMake subproject. They can be enabled by settingFMT_DOC
,FMT_INSTALL
, andFMT_TEST
in the parent project.
Thanks @niosHD.
- The code have been moved to the
2.0.1 - 2016-03-13
- Improved CMake find and package support (https://github.com/fmtlib/fmt/issues/264). Thanks @niosHD.
- Fix compile error with Android NDK and mingw32 (https://github.com/fmtlib/fmt/issues/241). Thanks @Gachapen.
- Documentation fixes (https://github.com/fmtlib/fmt/issues/248, https://github.com/fmtlib/fmt/issues/260).
2.0.0 - 2015-12-01
General
-
Breaking
(https://github.com/fmtlib/fmt/pull/169, https://github.com/fmtlib/fmt/pull/173, https://github.com/fmtlib/fmt/pull/174):
fmt::print("The answer is {answer}.", fmt::arg("answer", 42));
Thanks @jamboree.
-
Experimental
arguments (https://github.com/fmtlib/fmt/pull/204, https://github.com/fmtlib/fmt/pull/206, https://github.com/fmtlib/fmt/pull/207):
using namespace fmt::literals; fmt::print("The answer is {answer}.", "answer"_a=42);
Thanks @dean0x7d.
-
Breaking
when using variadic templates (https://github.com/fmtlib/fmt/issues/141). Thanks @Shauren.
-
Runtime width specification (https://github.com/fmtlib/fmt/pull/168):
fmt::format("{0:{1}}", 42, 5); // gives " 42"
Thanks @jamboree.
-
Breaking
std::ostream
insertion operator (operator<<
) if available (https://github.com/fmtlib/fmt/issues/232). -
Breaking
"false" (https://github.com/fmtlib/fmt/issues/170):
fmt::print("{}", true); // prints "true"
To print
bool
as a number use numeric format specifier such asd
:fmt::print("{:d}", true); // prints "1"
-
fmt::printf
andfmt::sprintf
now support formatting ofbool
with the%s
specifier giving textual output, "true" or "false" (https://github.com/fmtlib/fmt/pull/223):fmt::printf("%s", true); // prints "true"
Thanks @LarsGullik.
-
Breaking
integers by default (https://github.com/fmtlib/fmt/pull/217).
-
Breaking
specifier (https://github.com/fmtlib/fmt/pull/223):
fmt::print("{:p}", "test"); // prints pointer value
Thanks @LarsGullik.
-
Breaking
pointers as
(nil)
and null strings as(null)
for consistency with glibc (https://github.com/fmtlib/fmt/pull/226). Thanks @LarsGullik. -
Breaking
user-defined types that provide an overloaded
std::ostream
insertion operator (operator<<
) (https://github.com/fmtlib/fmt/issues/201):fmt::printf("The date is %s", Date(2012, 12, 9));
-
Breaking
can be used to implement custom memory buffers (https://github.com/fmtlib/fmt/issues/140). Thanks @polyvertex.
-
Breaking
std::experimental::basic_string_view (https://github.com/fmtlib/fmt/issues/100, https://github.com/fmtlib/fmt/issues/159, https://github.com/fmtlib/fmt/issues/183):
- Comparison operators now compare string content, not pointers
BasicStringRef::c_str
replaced byBasicStringRef::data
BasicStringRef
is no longer assumed to be null-terminated
References to null-terminated strings are now represented by a new class,
BasicCStringRef
. -
Dependency on pthreads introduced by Google Test is now optional (https://github.com/fmtlib/fmt/issues/185).
-
New CMake options
FMT_DOC
,FMT_INSTALL
andFMT_TEST
to control generation ofdoc
,install
andtest
targets respectively, on by default (https://github.com/fmtlib/fmt/issues/197, https://github.com/fmtlib/fmt/issues/198, https://github.com/fmtlib/fmt/issues/200). Thanks @maddinat0r. -
noexcept
is now used when compiling with MSVC2015 (https://github.com/fmtlib/fmt/pull/215). Thanks @dmkrepo. -
Added an option to disable use of
windows.h
whenFMT_USE_WINDOWS_H
is defined as 0 before includingformat.h
(https://github.com/fmtlib/fmt/issues/171). Thanks @alfps. -
Breaking
FMT_WIN_MINMAX
is defined. This is done to prevent breaking code usingstd::min
andstd::max
and only affects the header-only configuration (https://github.com/fmtlib/fmt/issues/152, https://github.com/fmtlib/fmt/pull/153, https://github.com/fmtlib/fmt/pull/154). Thanks @DevO2012. -
Improved support for custom character types (https://github.com/fmtlib/fmt/issues/171). Thanks @alfps.
-
Added an option to disable use of IOStreams when
FMT_USE_IOSTREAMS
is defined as 0 before includingformat.h
(https://github.com/fmtlib/fmt/issues/205, https://github.com/fmtlib/fmt/pull/208). Thanks @JodiTheTigger. -
Improved detection of
isnan
,isinf
andsignbit
.
Optimization
- Made formatting of user-defined types more efficient with a custom stream buffer (https://github.com/fmtlib/fmt/issues/92, https://github.com/fmtlib/fmt/pull/230). Thanks @NotImplemented.
- Further improved performance of
fmt::Writer
on integer formatting and fixed a minor regression. Now it is ~7% faster thankarma::generate
on Karma's benchmark (https://github.com/fmtlib/fmt/issues/186). -
size](https://github.com/fmtlib/fmt#compile-time-and-code-bloat) (https://github.com/fmtlib/fmt/issues/143, https://github.com/fmtlib/fmt/pull/149).Breaking
Distribution
-
Breaking
${CMAKE_INSTALL_PREFIX}/include/cppformat
(https://github.com/fmtlib/fmt/issues/178). Thanks @jackyf. -
Breaking
for consistency with the project name and to avoid potential conflicts (https://github.com/fmtlib/fmt/issues/178). Thanks @jackyf.
-
C++ Format is now available in Debian GNU/Linux (stretch, sid) and derived distributions such as Ubuntu 15.10 and later (https://github.com/fmtlib/fmt/issues/155):
$ sudo apt-get install libcppformat1-dev
Thanks @jackyf.
-
Packages for Fedora and RHEL are now available. Thanks Dave Johansen.
-
C++ Format can now be installed via Homebrew on OS X (https://github.com/fmtlib/fmt/issues/157):
$ brew install cppformat
Thanks @ortho and Anatoliy Bulukin.
Documentation
- Migrated from ReadTheDocs to GitHub Pages for better responsiveness and reliability (https://github.com/fmtlib/fmt/issues/128). New documentation address is http://cppformat.github.io/.
- Added Building thedocumentation section to the documentation.
- Documentation build script is now compatible with Python 3 and newer pip versions. (https://github.com/fmtlib/fmt/pull/189, https://github.com/fmtlib/fmt/issues/209). Thanks @JodiTheTigger and @xentec.
- Documentation fixes and improvements (https://github.com/fmtlib/fmt/issues/36, https://github.com/fmtlib/fmt/issues/75, https://github.com/fmtlib/fmt/issues/125, https://github.com/fmtlib/fmt/pull/160, https://github.com/fmtlib/fmt/pull/161, https://github.com/fmtlib/fmt/issues/162, https://github.com/fmtlib/fmt/issues/165, https://github.com/fmtlib/fmt/issues/210). Thanks @syohex.
- Fixed out-of-tree documentation build (https://github.com/fmtlib/fmt/issues/177). Thanks @jackyf.
Fixes
-
Fixed
initializer_list
detection (https://github.com/fmtlib/fmt/issues/136). Thanks @Gachapen. -
Breaking
specifiers in
fmt::(s)printf
(https://github.com/fmtlib/fmt/issues/131, https://github.com/fmtlib/fmt/issues/139):enum { ANSWER = 42 }; fmt::printf("%d", ANSWER);
Thanks @Naios.
-
Improved compatibility with old versions of MinGW (https://github.com/fmtlib/fmt/issues/129, https://github.com/fmtlib/fmt/pull/130, https://github.com/fmtlib/fmt/issues/132). Thanks @cstamford.
-
Fixed a compile error on MSVC with disabled exceptions (https://github.com/fmtlib/fmt/issues/144).
-
Added a workaround for broken implementation of variadic templates in MSVC2012 (https://github.com/fmtlib/fmt/issues/148).
-
Placed the anonymous namespace within
fmt
namespace for the header-only configuration (https://github.com/fmtlib/fmt/issues/171). Thanks @alfps. -
Fixed issues reported by Coverity Scan (https://github.com/fmtlib/fmt/issues/187, https://github.com/fmtlib/fmt/issues/192).
-
Implemented a workaround for a name lookup bug in MSVC2010 (https://github.com/fmtlib/fmt/issues/188).
-
Fixed compiler warnings (https://github.com/fmtlib/fmt/issues/95, https://github.com/fmtlib/fmt/issues/96, https://github.com/fmtlib/fmt/pull/114, https://github.com/fmtlib/fmt/issues/135, https://github.com/fmtlib/fmt/issues/142, https://github.com/fmtlib/fmt/issues/145, https://github.com/fmtlib/fmt/issues/146, https://github.com/fmtlib/fmt/issues/158, https://github.com/fmtlib/fmt/issues/163, https://github.com/fmtlib/fmt/issues/175, https://github.com/fmtlib/fmt/issues/190, https://github.com/fmtlib/fmt/pull/191, https://github.com/fmtlib/fmt/issues/194, https://github.com/fmtlib/fmt/pull/196, https://github.com/fmtlib/fmt/issues/216, https://github.com/fmtlib/fmt/pull/218, https://github.com/fmtlib/fmt/pull/220, https://github.com/fmtlib/fmt/pull/229, https://github.com/fmtlib/fmt/issues/233, https://github.com/fmtlib/fmt/issues/234, https://github.com/fmtlib/fmt/pull/236, https://github.com/fmtlib/fmt/issues/281, https://github.com/fmtlib/fmt/issues/289). Thanks @seanmiddleditch, @dixlorenz, @CarterLi, @Naios, @fmatthew5876, @LevskiWeng, @rpopescu, @gabime, @cubicool, @jkflying, @LogicalKnight, @inguin and @Jopie64.
-
Fixed portability issues (mostly causing test failures) on ARM, ppc64, ppc64le, s390x and SunOS 5.11 i386 (https://github.com/fmtlib/fmt/issues/138, https://github.com/fmtlib/fmt/issues/179, https://github.com/fmtlib/fmt/issues/180, https://github.com/fmtlib/fmt/issues/202, https://github.com/fmtlib/fmt/issues/225, Red Hat Bugzilla Bug 1260297). Thanks @Naios, @jackyf and Dave Johansen.
-
Fixed a name conflict with macro
free
defined incrtdbg.h
when_CRTDBG_MAP_ALLOC
is set (https://github.com/fmtlib/fmt/issues/211). -
Fixed shared library build on OS X (https://github.com/fmtlib/fmt/pull/212). Thanks @dean0x7d.
-
Fixed an overload conflict on MSVC when
/Zc:wchar_t-
option is specified (https://github.com/fmtlib/fmt/pull/214). Thanks @slavanap. -
Improved compatibility with MSVC 2008 (https://github.com/fmtlib/fmt/pull/236). Thanks @Jopie64.
-
Improved compatibility with bcc32 (https://github.com/fmtlib/fmt/issues/227).
-
Fixed
static_assert
detection on Clang (https://github.com/fmtlib/fmt/pull/228). Thanks @dean0x7d.
1.1.0 - 2015-03-06
-
Added
BasicArrayWriter
, a class template that provides operations for formatting and writing data into a fixed-size array (https://github.com/fmtlib/fmt/issues/105 and https://github.com/fmtlib/fmt/issues/122):char buffer[100]; fmt::ArrayWriter w(buffer); w.write("The answer is {}", 42);
-
Added 0 A.D. and PenUltima Online (POL) to the list of notable projects using C++ Format.
-
C++ Format now uses MSVC intrinsics for better formatting performance (https://github.com/fmtlib/fmt/pull/115, https://github.com/fmtlib/fmt/pull/116, https://github.com/fmtlib/fmt/pull/118 and https://github.com/fmtlib/fmt/pull/121). Previously these optimizations where only used on GCC and Clang. Thanks @CarterLi and @objectx.
-
CMake install target (https://github.com/fmtlib/fmt/pull/119). Thanks @TrentHouliston.
You can now install C++ Format with
make install
command. -
Improved Biicode support (https://github.com/fmtlib/fmt/pull/98 and https://github.com/fmtlib/fmt/pull/104). Thanks @MariadeAnton and @franramirez688.
-
Improved support for building with Android NDK (https://github.com/fmtlib/fmt/pull/107). Thanks @newnon.
The android-ndk-example repository provides and example of using C++ Format with Android NDK:
-
Improved documentation of
SystemError
andWindowsError
(https://github.com/fmtlib/fmt/issues/54). -
Various code improvements (https://github.com/fmtlib/fmt/pull/110, https://github.com/fmtlib/fmt/pull/111 https://github.com/fmtlib/fmt/pull/112). Thanks @CarterLi.
-
Improved compile-time errors when formatting wide into narrow strings (https://github.com/fmtlib/fmt/issues/117).
-
Fixed
BasicWriter::write
without formatting arguments when C++11 support is disabled (https://github.com/fmtlib/fmt/issues/109). -
Fixed header-only build on OS X with GCC 4.9 (https://github.com/fmtlib/fmt/issues/124).
-
Fixed packaging issues (https://github.com/fmtlib/fmt/issues/94).
1.0.0 - 2015-02-05
-
Add support for a header-only configuration when
FMT_HEADER_ONLY
is defined before includingformat.h
:#define FMT_HEADER_ONLY #include "format.h"
-
Compute string length in the constructor of
BasicStringRef
instead of thesize
method (https://github.com/fmtlib/fmt/issues/79). This eliminates size computation for string literals on reasonable optimizing compilers. -
Fix formatting of types with overloaded
operator <<
forstd::wostream
(https://github.com/fmtlib/fmt/issues/86):fmt::format(L"The date is {0}", Date(2012, 12, 9));
-
Fix linkage of tests on Arch Linux (https://github.com/fmtlib/fmt/issues/89).
-
Allow precision specifier for non-float arguments (https://github.com/fmtlib/fmt/issues/90):
fmt::print("{:.3}\n", "Carpet"); // prints "Car"
-
Fix build on Android NDK (https://github.com/fmtlib/fmt/issues/93).
-
Improvements to documentation build procedure.
-
Remove
FMT_SHARED
CMake variable in favor of standard BUILD_SHARED_LIBS. -
Fix error handling in
fmt::fprintf
. -
Fix a number of warnings.
0.12.0 - 2014-10-25
-
Breaking
management.
Writer
is now a base class that cannot be instantiated directly. The newMemoryWriter
class implements the default buffer management with small allocations done on stack. Sofmt::Writer
should be replaced withfmt::MemoryWriter
in variable declarations.Old code:
fmt::Writer w;
New code:
fmt::MemoryWriter w;
If you pass
fmt::Writer
by reference, you can continue to do so:void f(fmt::Writer &w);
This doesn't affect the formatting API.
-
Support for custom memory allocators (https://github.com/fmtlib/fmt/issues/69)
-
Formatting functions now accept [signed char]{.title-ref} and [unsigned char]{.title-ref} strings as arguments (https://github.com/fmtlib/fmt/issues/73):
auto s = format("GLSL version: {}", glGetString(GL_VERSION));
-
Reduced code bloat. According to the new benchmark results, cppformat is close to
printf
and by the order of magnitude better than Boost Format in terms of compiled code size. -
Improved appearance of the documentation on mobile by using the Sphinx Bootstrap theme:
Old New
0.11.0 - 2014-08-21
-
Safe printf implementation with a POSIX extension for positional arguments:
fmt::printf("Elapsed time: %.2f seconds", 1.23); fmt::printf("%1$s, %3$d %2$s", weekday, month, day);
-
Arguments of
char
type can now be formatted as integers (Issue https://github.com/fmtlib/fmt/issues/55):fmt::format("0x{0:02X}", 'a');
-
Deprecated parts of the API removed.
-
The library is now built and tested on MinGW with Appveyor in addition to existing test platforms Linux/GCC, OS X/Clang, Windows/MSVC.
0.10.0 - 2014-07-01
Improved API
-
All formatting methods are now implemented as variadic functions instead of using
operator<<
for feeding arbitrary arguments into a temporary formatter object. This works both with C++11 where variadic templates are used and with older standards where variadic functions are emulated by providing lightweight wrapper functions defined with theFMT_VARIADIC
macro. You can use this macro for defining your own portable variadic functions:void report_error(const char *format, const fmt::ArgList &args) { fmt::print("Error: {}"); fmt::print(format, args); } FMT_VARIADIC(void, report_error, const char *) report_error("file not found: {}", path);
Apart from a more natural syntax, this also improves performance as there is no need to construct temporary formatter objects and control arguments' lifetimes. Because the wrapper functions are very lightweight, this doesn't cause code bloat even in pre-C++11 mode.
-
Simplified common case of formatting an
std::string
. Now it requires a single function call:std::string s = format("The answer is {}.", 42);
Previously it required 2 function calls:
std::string s = str(Format("The answer is {}.") << 42);
Instead of unsafe
c_str
function,fmt::Writer
should be used directly to bypass creation ofstd::string
:fmt::Writer w; w.write("The answer is {}.", 42); w.c_str(); // returns a C string
This doesn't do dynamic memory allocation for small strings and is less error prone as the lifetime of the string is the same as for
std::string::c_str
which is well understood (hopefully). -
Improved consistency in naming functions that are a part of the public API. Now all public functions are lowercase following the standard library conventions. Previously it was a combination of lowercase and CapitalizedWords. Issue https://github.com/fmtlib/fmt/issues/50.
-
Old functions are marked as deprecated and will be removed in the next release.
Other Changes
-
Experimental support for printf format specifications (work in progress):
fmt::printf("The answer is %d.", 42); std::string s = fmt::sprintf("Look, a %s!", "string");
-
Support for hexadecimal floating point format specifiers
a
andA
:print("{:a}", -42.0); // Prints -0x1.5p+5 print("{:A}", -42.0); // Prints -0X1.5P+5
-
CMake option
FMT_SHARED
that specifies whether to build format as a shared library (off by default).
0.9.0 - 2014-05-13
-
More efficient implementation of variadic formatting functions.
-
Writer::Format
now has a variadic overload:Writer out; out.Format("Look, I'm {}!", "variadic");
-
For efficiency and consistency with other overloads, variadic overload of the
Format
function now returnsWriter
instead ofstd::string
. Use thestr
function to convert it tostd::string
:std::string s = str(Format("Look, I'm {}!", "variadic"));
-
Replaced formatter actions with output sinks:
NoAction
->NullSink
,Write
->FileSink
,ColorWriter
->ANSITerminalSink
. This improves naming consistency and shouldn't affect client code unless these classes are used directly which should be rarely needed. -
Added
ThrowSystemError
function that formats a message and throwsSystemError
containing the formatted message and system-specific error description. For example, the following codeFILE *f = fopen(filename, "r"); if (!f) ThrowSystemError(errno, "Failed to open file '{}'") << filename;
will throw
SystemError
exception with description "Failed to open file '<filename>': No such file or directory" if file doesn't exist. -
Support for AppVeyor continuous integration platform.
-
Format
now throwsSystemError
in case of I/O errors. -
Improve test infrastructure. Print functions are now tested by redirecting the output to a pipe.
0.8.0 - 2014-04-14
- Initial release