[libcxx-commits] [libcxx] [libc++][NFC] Simplify the implementation of string and string_views operator== (PR #117184)

[Louis Dionne via libcxx-commits]

================
@@ -755,51 +758,32 @@ operator==(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _
   return __lhs.compare(__rhs) == 0;
 }
 
-// The dummy default template parameters are used to work around a MSVC issue with mangling, see VSO-409326 for details.
-// This applies to the other sufficient overloads below for the other comparison operators.
-template <class _CharT, class _Traits, int = 1>
-_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
-operator==(basic_string_view<_CharT, _Traits> __lhs,
-           __type_identity_t<basic_string_view<_CharT, _Traits> > __rhs) _NOEXCEPT {
-  if (__lhs.size() != __rhs.size())
-    return false;
-  return __lhs.compare(__rhs) == 0;
-}
-
 template <class _CharT, class _Traits, int = 2>
 _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
 operator==(__type_identity_t<basic_string_view<_CharT, _Traits> > __lhs,
            basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
-  if (__lhs.size() != __rhs.size())
-    return false;
-  return __lhs.compare(__rhs) == 0;
+  return __lhs == __rhs;
----------------
ldionne wrote:

But how are these overloads not ambiguous with the one that takes two `basic_string_view`s when you pass actual string views (that match both overloads)?

https://github.com/llvm/llvm-project/pull/117184