[libcxx-commits] [libcxx] [libcxx] Unifying __is_trivial_equality_predicate and __is_trivial_plus_operation into __desugars_to (PR #68642)

[Louis Dionne via libcxx-commits]

================
@@ -26,8 +27,8 @@ struct __equal_to {
   }
 };
 
-template <class _Lhs, class _Rhs>
-struct __is_trivial_equality_predicate<__equal_to, _Lhs, _Rhs> : true_type {};
+template <>
+struct __desugars_to<__equal_to, std::equal_to<>> : true_type {};
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ldionne wrote:

One consideration is that since `equal_to<>` isn't valid in all standard modes, we should probably explicitly use `equal_to<void>` explicitly in places that need to work in C++03.

https://github.com/llvm/llvm-project/pull/68642