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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17
// <iterator>
// move_sentinel
// template<class S2>
// requires assignable_from<S&, const S2&>
// constexpr move_sentinel& operator=(const move_sentinel<S2>& s);
#include <cassert>
#include <concepts>
#include <iterator>
#include <type_traits>
struct NonAssignable {
NonAssignable& operator=(int i);
};
static_assert(std::semiregular<NonAssignable>);
static_assert(std::is_assignable_v<NonAssignable, int>);
static_assert(!std::assignable_from<NonAssignable, int>);
constexpr bool test()
{
// Assigning from an lvalue.
{
std::move_sentinel<int> m(42);
std::move_sentinel<long> m2;
m2 = m;
assert(m2.base() == 42L);
}
// Assigning from an rvalue.
{
std::move_sentinel<long> m2;
m2 = std::move_sentinel<int>(43);
assert(m2.base() == 43L);
}
// SFINAE checks.
{
static_assert( std::is_assignable_v<std::move_sentinel<int>, std::move_sentinel<long>>);
static_assert(!std::is_assignable_v<std::move_sentinel<int*>, std::move_sentinel<const int*>>);
static_assert( std::is_assignable_v<std::move_sentinel<const int*>, std::move_sentinel<int*>>);
static_assert(!std::is_assignable_v<std::move_sentinel<NonAssignable>, std::move_sentinel<int>>);
}
return true;
}
int main(int, char**)
{
test();
static_assert(test());
return 0;
}
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