1.0.0

• Add support for a header-only configuration when FMT_HEADER_ONLY is defined before including format.h:

  #define FMT_HEADER_ONLY
  #include "format.h"
  

• Compute string length in the constructor of BasicStringRef instead of the size method (#79). This eliminates size computation for string literals on reasonable optimizing compilers.

• Fix formatting of types with overloaded operator << for std::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 standard BUILD_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 new MemoryWriter class implements the default buffer management with small allocations done on stack. So fmt::Writer should be replaced with fmt::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 and unsigned 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

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 the FMT_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 of std::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 and A:

  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 returns Writer instead of std::string. Use the str function to convert it to std::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 throws SystemError containing the formatted message and system-specific error description. For example, the following code

  FILE *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 throws SystemError in case of I/O errors.

• Improve test infrastructure. Print functions are now tested by redirecting the output to a pipe.

0.8.0

Initial release