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// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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
// See https://llvm.org/PR31384.
#include <tuple>
#include <cassert>
#include "test_macros.h"
int count = 0;
struct Explicit {
Explicit() = default;
explicit Explicit(int) {}
};
struct Implicit {
Implicit() = default;
Implicit(int) {}
};
template<class T>
struct Derived : std::tuple<T> {
using std::tuple<T>::tuple;
template<class U>
operator std::tuple<U>() && { ++count; return {}; }
};
template<class T>
struct ExplicitDerived : std::tuple<T> {
using std::tuple<T>::tuple;
template<class U>
explicit operator std::tuple<U>() && { ++count; return {}; }
};
int main(int, char**) {
{
std::tuple<Explicit> foo = Derived<int>{42}; ((void)foo);
assert(count == 1);
Derived<int> d{42};
std::tuple<Explicit> bar(std::move(d)); ((void)bar);
#if TEST_STD_VER < 17
assert(count == 1);
#else
assert(count == 2);
#endif
}
count = 0;
{
std::tuple<Implicit> foo = Derived<int>{42}; ((void)foo);
assert(count == 1);
Derived<int> d{42};
std::tuple<Implicit> bar(std::move(d)); ((void)bar);
#if TEST_STD_VER < 17
assert(count == 1);
#else
assert(count == 2);
#endif
}
count = 0;
{
static_assert(!std::is_convertible<ExplicitDerived<int>, std::tuple<Explicit>>::value, "");
ExplicitDerived<int> d{42};
std::tuple<Explicit> bar(std::move(d)); ((void)bar);
#if TEST_STD_VER < 17
assert(count == 0);
#else
assert(count == 1);
#endif
}
count = 0;
{
std::tuple<Implicit> foo = ExplicitDerived<int>{42}; ((void)foo);
static_assert(std::is_convertible<ExplicitDerived<int>, std::tuple<Implicit>>::value, "");
assert(count == 0);
ExplicitDerived<int> d{42};
std::tuple<Implicit> bar(std::move(d)); ((void)bar);
#if TEST_STD_VER < 17
assert(count == 0);
#else
assert(count == 1);
#endif
}
count = 0;
return 0;
}
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