[libcxx-commits] [libcxx] [libc++] Make optional::iterator experimental (PR #173470)

[A. Jiang via libcxx-commits]

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@@ -681,6 +681,8 @@ struct __is_std_optional<optional<_Tp>> : true_type {};
 template <class _Tp, class = void>
 struct __optional_iterator {};
 
+#    if _LIBCPP_HAS_EXPERIMENTAL_OPTIONAL_ITERATOR
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frederick-vs-ja wrote:

We should also guard the FTM (`__cpp_lib_optional_range_support`).

https://github.com/llvm/llvm-project/pull/173470