[libcxx-commits] [PATCH] D99855: [libcxx] makes `iterator_traits` C++20-aware

[Christopher Di Bella via Phabricator via libcxx-commits]

cjdb added inline comments.


================
Comment at: libcxx/include/iterator:702-707
+  __has_member_reference<_Ip> &&
+  __has_member_iterator_category<_Ip> &&
+  requires {
+    typename _Ip::difference_type;
+    typename _Ip::value_type;
+  };
----------------
zoecarver wrote:
> cjdb wrote:
> > I know I wrote this, but it'd be better if we used nested requires expressions so the requirements can be congruently ordered with the wording.
> Not sure I follow. Do you want me to make this two `requires` expressions, or do you want me to add `__has_member_{difference_type,value_type}`?
```
  requires {
    typename _Ip::value_type;
    typename _Ip::difference_type;
    requires __has_member_reference<_Ip>; // this is a nested-requires-expression
    requires __has_member_iterator_category<_Ip>;
  };
```
However, you did point out that the ordering of wording is subject to change, so perhaps this is a moot point to discuss.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D99855/new/

https://reviews.llvm.org/D99855