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README.md
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README.md
@ -380,82 +380,11 @@ If you are aware of other projects using this library, please let me
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know by [email](mailto:victor.zverovich@gmail.com) or by submitting an
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[issue](https://github.com/fmtlib/fmt/issues).
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# Motivation
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# Sponsors
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So why yet another formatting library?
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There are plenty of methods for doing this task, from standard ones like
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the printf family of function and iostreams to Boost Format and
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FastFormat libraries. The reason for creating a new library is that
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every existing solution that I found either had serious issues or
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didn\'t provide all the features I needed.
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## printf
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The good thing about `printf` is that it is pretty fast and readily
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available being a part of the C standard library. The main drawback is
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that it doesn\'t support user-defined types. `printf` also has safety
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issues although they are somewhat mitigated with [\_\_attribute\_\_
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((format (printf,
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\...))](https://gcc.gnu.org/onlinedocs/gcc/Common-Attributes.html) in
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GCC. There is a POSIX extension that adds positional arguments required
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for
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[i18n](https://en.wikipedia.org/wiki/Internationalization_and_localization)
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to `printf` but it is not a part of C99 and may not be available on some
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platforms.
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## iostreams
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The main issue with iostreams is best illustrated with an example:
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``` c++
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std::cout << std::setprecision(2) << std::fixed << 1.23456 << "\n";
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```
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which is a lot of typing compared to printf:
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``` c++
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printf("%.2f\n", 1.23456);
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```
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Matthew Wilson, the author of FastFormat, called this \"chevron hell\".
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iostreams don\'t support positional arguments by design.
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The good part is that iostreams support user-defined types and are safe
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although error handling is awkward.
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## Boost Format
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This is a very powerful library that supports both `printf`-like format
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strings and positional arguments. Its main drawback is performance.
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According to various benchmarks, it is much slower than other methods
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considered here. Boost Format also has excessive build times and severe
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code bloat issues (see [Benchmarks](#benchmarks)).
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## FastFormat
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This is an interesting library that is fast, safe and has positional
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arguments. However, it has significant limitations, citing its author:
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> Three features that have no hope of being accommodated within the
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> current design are:
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>
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> - Leading zeros (or any other non-space padding)
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> - Octal/hexadecimal encoding
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> - Runtime width/alignment specification
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It is also quite big and has a heavy dependency, on STLSoft, which might be
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too restrictive for use in some projects.
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## Boost Spirit.Karma
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This is not a formatting library but I decided to include it here for
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completeness. As iostreams, it suffers from the problem of mixing
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verbatim text with arguments. The library is pretty fast, but slower on
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integer formatting than `fmt::format_to` with format string compilation
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on Karma\'s own benchmark, see [Converting a hundred million integers to
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strings per
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second](http://www.zverovich.net/2020/06/13/fast-int-to-string-revisited.html).
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{fmt} development is supported by individual sponsors. If you find this
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library useful, please consider [sponsoring its development on GitHub
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Sponsors](https://github.com/sponsors/vitaut).
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# License
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