[libcxx-commits] [PATCH] D112017: [libcxx][format] Fix how we handle char traits in formatter<string> and formatter<string_view>

[Mark de Wever via Phabricator via libcxx-commits]

Mordante added a comment.

Nice catch!



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Comment at: libcxx/include/__format/formatter_string.h:134
       -> decltype(__ctx.out()) {
-    return _Base::format(_VSTD::basic_string_view<_CharT>(__str), __ctx);
+    return _Base::format(_VSTD::basic_string_view<_CharT, _Traits>(__str), __ctx);
   }
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I think we can here directly convert to a `VSTD::basic_string_view<_CharT>` and drop the `_Traits`.


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Comment at: libcxx/include/__format/formatter_string.h:141
+struct _LIBCPP_TEMPLATE_VIS _LIBCPP_AVAILABILITY_FORMAT formatter<basic_string_view<_CharT, _Traits>, _CharT>
+    : public __format_spec::__formatter_string<_CharT, _Traits> {};
 
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I even wonder whether we want to drop the `_Traits` here and have no `_Traits` for `__formatter_string`.
When a string(_view) is stored as `format_arg` the traits and allocator are stripped http://eel.is/c++draft/format#arg-9


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D112017/new/

https://reviews.llvm.org/D112017