4.0.0

• Removed old compatibility headers cppformat/*.h and CMake options (#527). Thanks @maddinat0r (Alex Martin).

• Added string.h containing fmt::to_string() as alternative to std::to_string() as well as other string writer functionality (#326 and #441):

  #include "fmt/string.h"
  
  std::string answer = fmt::to_string(42);

  Thanks to @glebov-andrey (Andrey Glebov).

• Moved fmt::printf() to new printf.h header and allowed %s as generic specifier (#453), made %.f more conformant to regular printf() (#490), added custom writer support (#476) and implemented missing custom argument formatting (#339 and #340):

  #include "fmt/printf.h"
  
  // %s format specifier can be used with any argument type.
  fmt::printf("%s", 42);

  Thanks @mojoBrendan, @manylegged (Arthur Danskin) and @spacemoose (Glen Stark). See also #360, #335 and #331.

• Added container.h containing a BasicContainerWriter to write to containers like std::vector (#450). Thanks @polyvertex (Jean-Charles Lefebvre).

• Added fmt::join() function that takes a range and formats its elements separated by a given string (#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 (#444). Thanks @polyvertex (Jean-Charles Lefebvre). See also #439.

• Added fmt::format_system_error() for error code formatting (#323 and #526). Thanks @maddinat0r (Alex Martin).

• Added thread-safe fmt::localtime() and fmt::gmtime() as replacement for the standard version to time.h (#396). Thanks @codicodi.

• Internal improvements to NamedArg and ArgLists (#389 and #390). Thanks @chronoxor.

• Fixed crash due to bug in FormatBuf (#493). Thanks @effzeh. See also #480 and #491.

• Fixed handling of wide strings in fmt::StringWriter.

• Improved compiler error messages (#357).

• Fixed various warnings and issues with various compilers (#494, #499, #483, #519, #485, #482, #475, #473 and #414). Thanks @chronoxor, @zhaohuaxishi, @pkestene (Pierre Kestener), @dschmidt (Dominik Schmidt) and @0x414c (Alexey Gorishny) .

• Improved CMake: targets are now namespaced (#511 and #513), supported header-only printf.h (#354), fixed issue with minimal supported library subset (#418, #419 and #420). Thanks @bjoernthiel (Bjoern Thiel), @niosHD (Mario Werner), @LogicalKnight (Sean LK) and @alabuzhev (Alex Alabuzhev).

• Improved documentation. Thanks to @pwm1234 (Phil) for #393.