[libcxx-commits] [libcxx] [libc++] optimization on ranges::drop_view::begin (#72883) (PR #72929)

[Will Hawkins via libcxx-commits]

hawkinsw wrote:

Are we missing another optimization here, too? 

For the non-`const` version of `begin()`, it could be possible for `__simple_view<_View>` to be the only one of the three conditions to fail. That would get us to exactly the same place as the requirements for the `const` version of `begin()`, just called on a non-`const` `drop_view`. So, should there be an optimization here, too (as in, obviating the need for caching)? 

https://github.com/llvm/llvm-project/pull/72929