[libcxx-commits] [libcxx] [libc++] Implement LWG3940: std::expected<void, E>::value() also needs E to be copy constructible (PR #71819)

[A. Jiang via libcxx-commits]

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@@ -65,17 +65,6 @@ void testException() {
     }
   }
 
-  // MoveOnly
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frederick-vs-ja wrote:

It seems that `throw NonCopyable(args)` also needs result in substitution failure, while Clang currently disagrees ([example](https://godbolt.org/z/x1j16E54K)). See also [this article](https://quuxplusone.github.io/blog/2021/03/18/sfinae-on-throw-x/).

https://github.com/llvm/llvm-project/pull/71819