[libcxx-commits] [PATCH] D96523: [libc++] Rewrite the tuple constructors to be strictly Standards conforming

[Zoe Carver via Phabricator via libcxx-commits]

zoecarver added inline comments.


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Comment at: libcxx/include/tuple:585
+        _BoolConstant<sizeof...(_Tp) >= 1>,
+        _Not<_IsThisTuple<_Up...> >, // extension to allow mis-behaved user constructors
+        is_constructible<_Tp, _Up>...
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Nit: it might be simpler to just say `sizeof...(_Up) != 1 || is_same<_Up,  tuple>...` (or even `__is_same(_Up..., tuple)`). Then you could get rid of `_IsThisTuple`.


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Comment at: libcxx/include/tuple:917
+        _And<_Dep,
+            _Lazy<_EnableMoveFromPair, _Up1, _Up2>,
+            _Not<_Lazy<_And, // explicit check
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If you're using `_Up1` here, do you need the `_Dep` template type param?


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Comment at: libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_copy.pass.cpp:57
-#ifdef _LIBCPP_VERSION
     {
         typedef std::tuple<alloc_first, alloc_last> T;
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Is this not an extension? If it is an extension, don't we want to keep this behind a condition so that the test suite is more portable?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D96523/new/

https://reviews.llvm.org/D96523