[libcxx-commits] [libcxx] [libc++] Replace `std::optional` in `__format/format_context.h` with a re-implementation (PR #148876)

[Nikolas Klauser via libcxx-commits]

philnik777 wrote:

If we just need `range_format` then I think we should just include that in `<optional>` If we do need to include more formatter stuff then I agree we should granularize `<optional>`.

https://github.com/llvm/llvm-project/pull/148876