[libcxx-commits] [libcxx] [libc++] Refactor internal index_sequence API to match the public one (PR #149475)

[via libcxx-commits]

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@@ -17,74 +17,60 @@
 #  pragma GCC system_header
 #endif
 
+#ifndef _LIBCPP_CXX03_LANG
+
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-template <size_t...>
-struct __tuple_indices;
+#  if __has_builtin(__make_integer_seq)
+template <template <class _Tp, _Tp...> class _BaseType, class _Tp, _Tp _SequenceSize>
+using __make_integer_sequence_impl _LIBCPP_NODEBUG = __make_integer_seq<_BaseType, _Tp, _SequenceSize>;
+#  else
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Kim-J-Smith wrote:

Why is the fallback implementation not retained here?

https://github.com/llvm/llvm-project/pull/149475