maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[libcxx][NFC] removes `swap`'s dependency on `swap_ranges` 

Under the as-if rule, we can directly implement the array overload for
`std::swap`. By removing this circular dependency where `swap` is
implemented in terms of `swap_ranges` and `swap_ranges` is defined in
terms of `swap`, we can split them into their own headers. This will:

* limit the surface area in which Hyrum's law can bite us;
* force users to include the correct headers;
* make finding the definitions trivial (`swap` is a utility;
  `swap_ranges` is an algorithm).

Differential Revision: https://reviews.llvm.org/D104760
This commit is contained in:
Christopher Di Bella 2021-06-23 01:25:31 +00:00
parent 652f4b5140
commit d87f159ab6
1 changed files with 3 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
libcxx/include/type_traits
View File

@ -4190,11 +4190,6 @@ template <class _Tp> struct __is_nothrow_swappable;
// swap, swap_ranges
template <class _ForwardIterator1, class _ForwardIterator2>
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
_ForwardIterator2
swap_ranges(_ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2);
#ifndef _LIBCPP_CXX03_LANG
template <class _Tp>
using __swap_result_t = typename enable_if<is_move_constructible<_Tp>::value && is_move_assignable<_Tp>::value>::type;
@ -4221,7 +4216,9 @@ typename enable_if<
>::type
swap(_Tp (&__a)[_Np], _Tp (&__b)[_Np]) _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value)
{
_VSTD::swap_ranges(__a, __a + _Np, __b);
for (size_t __i = 0; __i != _Np; ++__i) {
swap(__a[__i], __b[__i]);
}
}
template <class _ForwardIterator1, class _ForwardIterator2>