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From: "cooky.ykooc922 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/107761] Implement C++23 <mdspan>
Date: Tue, 26 Dec 2023 13:39:07 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107761

--- Comment #7 from Desmond Gold <cooky.ykooc922 at gmail dot com> ---
Here's an updated version of the implementation with following changes:
+ followed coding style of GNU (maybe not all)
+ added initial implementation of std::submdspan facilities (without
constraints and preconditions yet)
+ tweaked some of the problems in previous implementation

https://godbolt.org/z/Mxs1YP8n7

summary
+ implemented c++23 <mdspan>
+ implemented c++26 std::submdspan facilities in <mdspan>
  + added c++23 feature (concepts only): '__tuple_like' and '__pair_like'
    to be used by '__mdspan::__index_pair_like'
  + added alias template '_Nth_type_t' which would supposedly be placed
    inside <bits/utility.h>
+ still no documentations, incomplete preconditions and constraints, and
incomplete tests=