[libcxx-commits] [libcxx] [libc++] Avoid code duplication in strings operator+ overloads (PR #126048)

[Louis Dionne via libcxx-commits]

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@@ -3986,83 +3940,73 @@ operator>=(const _CharT* __lhs, const basic_string<_CharT, _Traits, _Allocator>&
 
 template <class _CharT, class _Traits, class _Allocator>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
-operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
-          const basic_string<_CharT, _Traits, _Allocator>& __rhs) {
+__concatenate_strings(const _Allocator& __alloc,
+                      __type_identity_t<basic_string_view<_CharT, _Traits> > __str1,
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ldionne wrote:

Why are you using `__type_identity_t` here?

https://github.com/llvm/llvm-project/pull/126048