fmt

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**{fmt}** is an open-source formatting library providing a fast and safe
alternative to C stdio and C++ iostreams.

[Documentation](https://fmt.dev)

[Cheat Sheets](https://hackingcpp.com/cpp/libs/fmt.html)

Q&A: ask questions on [StackOverflow with the tag
fmt](https://stackoverflow.com/questions/tagged/fmt).

Try {fmt} in [Compiler Explorer](https://godbolt.org/z/8Mx1EW73v).

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# Features

- Simple [format API](https://fmt.dev/latest/api/) with positional
  arguments for localization
- Implementation of [C++20
  std::format](https://en.cppreference.com/w/cpp/utility/format) and
  [C++23 std::print](https://en.cppreference.com/w/cpp/io/print)
- [Format string syntax](https://fmt.dev/latest/syntax/) similar
  to Python\'s
  [format](https://docs.python.org/3/library/stdtypes.html#str.format)
- Fast IEEE 754 floating-point formatter with correct rounding,
  shortness and round-trip guarantees using the
  [Dragonbox](https://github.com/jk-jeon/dragonbox) algorithm
- Portable Unicode support
- Safe [printf
  implementation](https://fmt.dev/latest/api/#printf-api)
  including the POSIX extension for positional arguments
- Extensibility: [support for user-defined
  types](https://fmt.dev/latest/api/#formatting-user-defined-types)
- High performance: faster than common standard library
  implementations of `(s)printf`, iostreams, `to_string` and
  `to_chars`, see [Speed tests](#speed-tests) and [Converting a
  hundred million integers to strings per
  second](https://vitaut.net