[libcxx-commits] [libcxx] [libc++] mark `std::expected` as `nodiscard` (PR #130820)

[Hans Wennborg via libcxx-commits]

zmodem wrote:

Chromium isn't on C++23 yet, so we're not using std::expected and I'm not really familiar with the class, but I did notice that our own "backport" is marked `[[nodiscard]]`: https://source.chromium.org/chromium/chromium/src/+/main:base/types/expected.h;l=273;drc=9596f8af68e7ad21da9bf94249e8a314edf09329

https://github.com/llvm/llvm-project/pull/130820