[libcxx-commits] [libcxx] [libc++][mdspan] P3383R3: `mdspan.at()` (PR #175213)

[A. Jiang via libcxx-commits]

================
@@ -273,6 +306,10 @@ class mdspan {
 
   template <class, class, class, class>
   friend class mdspan;
+
+#  if _LIBCPP_STD_VER >= 26
+  _LIBCPP_HIDE_FROM_ABI void __throw_out_of_range() const { std::__throw_out_of_range("mdspan"); }
----------------
frederick-vs-ja wrote:

Was it intended not to verify that the result of `what()` contains expected information (which is implementation-defined, though)?

If we want to test the result, I think we can use `LIBCPP_ASSERT(std::string_view(e.what()).contains("mdspan"));`.

https://github.com/llvm/llvm-project/pull/175213