Releases: fmtlib/fmt
2.0.1
2.0.0
General
-
[Breaking] Named arguments (#169, #173, #174):
fmt::print("The answer is {answer}.", fmt::arg("answer", 42));
Thanks to @jamboree.
-
[Experimental] User-defined literals for format and named arguments (#204, #206, #207):
using namespace fmt::literals; fmt::print("The answer is {answer}.", "answer"_a=42);
Thanks to @dean0x7d (Dean Moldovan).
-
[Breaking] Formatting of more than 16 arguments is now supported when using variadic templates (#141). Thanks to @Shauren.
-
Runtime width specification (#168):
fmt::format("{0:{1}}", 42, 5); // gives " 42"
Thanks to @jamboree.
-
[Breaking] Enums are now formatted with an overloaded
std::ostream
insertion operator (operator<<
) if available (#232). -
[Breaking] Changed default
bool
format to textual, "true" or "false" (#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" (#223):fmt::printf("%s", true); // prints "true"
Thanks to @LarsGullik.
-
[Breaking]
signed char
andunsigned char
are now formatted as integers by default (#217). -
[Breaking] Pointers to C strings can now be formatted with the
p
specifier (#223):fmt::print("{:p}", "test"); // prints pointer value
Thanks to @LarsGullik.
-
[Breaking]
fmt::printf
andfmt::sprintf
now print null pointers as(nil)
and null strings as(null)
for consistency with glibc (#226). Thanks to @LarsGullik. -
[Breaking]
fmt::(s)printf
now supports formatting of objects of user-defined types that provide an overloadedstd::ostream
insertion operator (operator<<
) (#201):fmt::printf("The date is %s", Date(2012, 12, 9));
-
[Breaking] The
Buffer
template is now part of the public API and can be used to implement custom memory buffers (#140). Thanks to @polyvertex (Jean-Charles Lefebvre). -
[Breaking] Improved compatibility between
BasicStringRef
and std::experimental::basic_string_view (#100, #159, #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 (#185).
-
New CMake options
FMT_DOC
,FMT_INSTALL
andFMT_TEST
to control generation ofdoc
,install
andtest
targets respectively, on by default (#197, #198, #200). Thanks to @maddinat0r (Alex Martin). -
noexcept
is now used when compiling with MSVC2015 (#215). Thanks to @dmkrepo (Dmitriy). -
Added an option to disable use of
windows.h
whenFMT_USE_WINDOWS_H
is defined as 0 before includingformat.h
(#171). Thanks to @alfps (Alf P. Steinbach). -
[Breaking]
windows.h
is now included withNOMINMAX
unlessFMT_WIN_MINMAX
is defined. This is done to prevent breaking code usingstd::min
andstd::max
and only affects the header-only configuration (#152, #153, #154). Thanks to @DevO2012. -
Improved support for custom character types (#171). Thanks to @alfps (Alf P. Steinbach).
-
Added an option to disable use of IOStreams when
FMT_USE_IOSTREAMS
is defined as 0 before includingformat.h
(#205, #208). Thanks to @JodiTheTigger. -
Improved detection of
isnan
,isinf
andsignbit
.
Optimization
- Made formatting of user-defined types more efficient with a custom stream buffer (#92, #230). Thanks to @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 (#186). - [Breaking] Reduced compiled code size (#143, #149).
Distribution
-
[Breaking] Headers are now installed in
${CMAKE_INSTALL_PREFIX}/include/cppformat
(#178). Thanks to @jackyf (Eugene V. Lyubimkin). -
[Breaking] Changed the library name from
format
tocppformat
for consistency with the project name and to avoid potential conflicts (#178). Thanks to @jackyf (Eugene V. Lyubimkin). -
C++ Format is now available in Debian GNU/Linux (stretch, sid) and derived distributions such as Ubuntu 15.10 and later (#155):
$ sudo apt-get install libcppformat1-dev
Thanks to @jackyf (Eugene V. Lyubimkin).
-
Packages for Fedora and RHEL are now available. Thanks to Dave Johansen.
-
C++ Format can now be installed via Homebrew on OS X (#157):
$ brew install cppformat
Thanks to @ortho, Anatoliy Bulukin.
Documentation
- Migrated from ReadTheDocs to GitHub Pages for better responsiveness and reliability (#128). New documentation address is http://cppformat.github.io/.
- Added Building the documentation section to the documentation.
- Documentation build script is now compatible with Python 3 and newer pip versions. (#189, #209). Thanks to @JodiTheTigger and @xentec.
- Documentation fixes and improvements (#36, #75, #125, #160, #161, #162, #165, #210). Thanks to @syohex (Syohei YOSHIDA) and bug reporters.
- Fixed out-of-tree documentation build (#177). Thanks to @jackyf (Eugene V. Lyubimkin).
Fixes
-
Fixed
initializer_list
detection (#136). Thanks to @Gachapen (Magnus Bjerke Vik). -
[Breaking] Fixed formatting of enums with numeric format specifiers in
fmt::(s)printf
(#131, #139):enum { ANSWER = 42 }; fmt::printf("%d", ANSWER);
Thanks to @Naios.
-
Improved compatibility with old versions of MinGW (#129, #130, #132). Thanks to @cstamford (Christopher Stamford).
-
Fixed a compile error on MSVC with disabled exceptions (#144).
-
Added a workaround for broken implementation of variadic templates in MSVC2012 (#148).
-
Placed the anonymous namespace within
fmt
namespace for the header-only configuration (#171). Thanks to @alfps (Alf P. Steinbach). -
Implemented a workaround for a name lookup bug in MSVC2010 (#188).
-
Fixed compiler warnings (#95, #96, #114, #135, #142, #145, #146, #158, #163, #175, #190, #191, #194, #196, #216, #218, #220, #229, #233, #234, #236). Thanks to @seanmiddleditch (Sean Middleditch), @dixlorenz (Dix Lorenz), @CarterLi (李通洲), @Naios, @fmatthew5876 (Matthew Fioravante), @LevskiWeng (Levski Weng), @rpopescu, @gabime (Gabi Melman), @cubicool (Jeremy Moles), @jkflying (Julian Kent), @LogicalKnight (Sean L), @inguin (Ingo van Lil) and @Jopie64 (Johan).
-
Fixed portability issues (mostly causing test failures) on ARM, ppc64, ppc64le, s390x and SunOS 5.11 i386 ( #138, #179, #180, #202, #225, Red Hat Bugzilla Bug 1260297). Thanks to @Naios, @jackyf (Eugene V. Lyubimkin) and Dave Johansen.
-
Fixed a name conflict with macro
free
defined incrtdbg.h
when_CRTDBG_MAP_ALLOC
is set (#211). -
Fixed shared library build on OS X (#212). Thanks to @dean0x7d (Dean Moldovan).
-
Fixed an overload conflict on MSVC when
/Zc:wchar_t-
option is specified (#214). Thanks to @slavanap (Vyacheslav Napadovsky). -
Improved compatibility with MSVC 2008 (#236). Thanks to @Jopie64 (Johan).
-
Improved compatibility with bcc32 (#227).
-
Fixed
static_assert
detection on Clang (#228). Thanks to @dean0x7d (Dean Moldovan).
1.1.0
- Added
BasicArrayWriter
, a class template that provides operations for formatting and writing data into a fixed-size array (#105 and #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 (#115, #116, #118 and #121). Previously these optimizations where only used on GCC and Clang. Thanks to @CarterLi and @objectx.
- CMake install target (#119). Thanks to @TrentHouliston.
You can now install C++ Format with make install
command.
- Improved Biicode support (#98 and #104). Thanks to @MariadeAnton and @franramirez688.
- Improved support for bulding with Android NDK (#107). Thanks to @newnon.
The android-ndk-example repository provides and example of using C++ Format with Android NDK:
- Improved documentation of
SystemError
andWindowsError
(#54). - Various code improvements (#110, #111 #112). Thanks to @CarterLi.
- Improved compile-time errors when formatting wide into narrow strings (#117).
- Fixed
BasicWriter::write
without formatting arguments when C++11 support is disabled (#109). - Fixed header-only build on OS X with GCC 4.9 (#124).
- Fixed packaging issues (#94).
- Fixed warnings in GCC, MSVC and Xcode/Clang (#95, #96 and #114).
- Added changelog (#103).
1.0.0
-
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 (#79). This eliminates size computation for string literals on reasonable optimizing compilers. -
Fix formatting of types with overloaded
operator <<
forstd::wostream
(#86):fmt::format(L"The date is {0}", Date(2012, 12, 9));
-
Fix linkage of tests on Arch Linux (#89).
-
Allow precision specifier for non-float arguments (#90):
fmt::print("{:.3}\n", "Carpet"); // prints "Car"
-
Fix build on Android NDK (#93)
-
Improvements to documentation build procedure.
-
Remove
FMT_SHARED
CMake variable in favor of standardBUILD_SHARED_LIBS
. -
Fix error handling in
fmt::fprintf
. -
Fix a number of warnings.
0.12.0
-
[Breaking] Improved separation between formatting and buffer 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 (#69)
-
Formatting functions now accept
signed char
andunsigned char
strings as arguments (#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 |
---|---|
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0.11.0
-
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 (#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
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 ligthweight, 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 #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
-
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.