[libcxx-commits] [libcxx] [libc++][NFC] Centralize test for support of == and != in ranges (PR #78481)

[Konstantin Varlamov via libcxx-commits]

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@@ -89,4 +91,12 @@ concept simple_view =
     std::same_as<std::ranges::iterator_t<Range>, std::ranges::iterator_t<const Range>> &&
     std::same_as<std::ranges::sentinel_t<Range>, std::ranges::sentinel_t<const Range>>;
 
+template <class T, class U = T>
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var-const wrote:

Optional: perhaps add a comment like `// [concept.equalitycomparable]` to indicate that this concept comes from the Standard (where it's exposition-only so we can't use it directly)?

https://github.com/llvm/llvm-project/pull/78481