[libcxx-commits] [libcxx] [libc++] Resolve LWG4308, correct `iterator` availability for `optional<T&>` (PR #173948)

[A. Jiang via libcxx-commits]

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frederick-vs-ja wrote:

It seems clearer to make inner test functions return `void`, while keeping the outermost `test` returning `bool`.

https://github.com/llvm/llvm-project/pull/173948