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Improvements to Std:Format in C++26

37 points by jandeboevrie

by veltas

3 subcomments

by draginol

0 subcomment

I'm more happy to see C++ moving to consolidate around a single formatting model.
This past year we were porting Elemental (PC game) to 64-bit so it's pretty old code. There are a gazillion different string types in it (sprintf and beyond).

by Longhanks

1 subcomments

> A related issue solved along was Windows string representation of paths. std::filesystem::path stores its text in wchar_t encoded as UTF-16 (Windows native). But p.string() narrows it down to the active code page, rather than UTF-8 which is what the formatting library expects. The result was a non-ASCII path could get transcoded to gibberish. The C++26 std::formatter<std::filesystem::path> converts Windows native UTC-16 to UTF-8 using Unicode transcoding and avoiding code pages, therefore solving the problem.
...only to then convert it back to UTF-16 for WriteConsoleW(), which std::print() usually calls (unless not running in a console) (https://github.com/microsoft/STL/blob/488e7953685722d2d6666f...).

by randusername

1 subcomments

> This makes it possible to use static_assert for instance with std::format...
This is great but it sounds like it doesn't work for floats yet
> For now, compile-time std::format covers integers, strings, and diagnostics well, with floating-point support waiting on a separate paper (P3652) to make the floating-point <charconv> functions constexpr.

by arunc

0 subcomment

Articles with code examples that doesn't show their output are just silly. This one deals with `std::println` to print pointer formatting with no output.