[libcxx-commits] [PATCH] D96657: [libcxx] adds common_reference to <type_traits>

[Michael Schellenberger Costa via Phabricator via libcxx-commits]

miscco added inline comments.


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Comment at: libcxx/include/type_traits:2471
+
+//            COMMON-REF(A, B) is COND-RES(COPYCV(X, Y) &, COPYCV(​Y, X) &)
+//            if that type exists and is a reference type.
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I think it would not hurt to add the standardese for X and Y too


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Comment at: libcxx/include/type_traits:2492
+
+//            Otherwise, let C be remove_­reference_­t<COMMON-REF(X&, Y&)>&&. If A and B are both
+//            rvalue reference types, C is well-formed, and ...
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Is there a reason for the deep identation?


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Comment at: libcxx/include/type_traits:2494
+//            rvalue reference types, C is well-formed, and ...
+template <class _Tp, class _Up>
+using __common_ref_C = remove_reference_t<__common_ref<_Tp&, _Up&>>&&;
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I think we should go with `_Xp` and `_Yp` here


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Comment at: libcxx/include/type_traits:2508
+//            Otherwise, let D be COMMON-REF(const X&, Y&).
+template <class _Tp, class _Up>
+using __common_ref_D = __common_ref<const _Tp&, _Up&>;
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Same would use `_Xp` and `_Yp`


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D96657/new/

https://reviews.llvm.org/D96657