[libcxx-commits] [libcxx] [libc++] P2770R0: "Stashing stashing iterators for proper flattening" (PR #66033)

[Jakub Mazurkiewicz via libcxx-commits]

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@@ -6407,6 +6409,9 @@ public:
     typedef const value_type*                     pointer;
     typedef const value_type&                     reference;
     typedef forward_iterator_tag                  iterator_category;
+#if _LIBCPP_STD_VER >= 20
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JMazurkiewicz wrote:

I don't think that this is good idea, `iterator_concept` has no meaning before C++20.

https://github.com/llvm/llvm-project/pull/66033