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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
//
//===----------------------------------------------------------------------===//
// <functional>
// reference_wrapper
// template <ObjectType T> reference_wrapper<T> ref(reference_wrapper<T> t);
#include <functional>
#include <cassert>
#include "counting_predicates.h"
#include "test_macros.h"
bool is5 ( int i ) { return i == 5; }
template <typename T>
bool call_pred ( T pred ) { return pred(5); }
namespace adl {
struct A {};
void ref(A) {}
}
TEST_CONSTEXPR_CXX20 bool test()
{
{
int i = 0;
std::reference_wrapper<int> r1 = std::ref(i);
std::reference_wrapper<int> r2 = std::ref(r1);
assert(&r2.get() == &i);
}
{
adl::A a;
std::reference_wrapper<adl::A> a1 = std::ref(a);
std::reference_wrapper<adl::A> a2 = std::ref(a1);
assert(&a2.get() == &a);
}
return true;
}
int main(int, char**)
{
test();
#if TEST_STD_VER > 17
static_assert(test());
#endif
{
unary_counting_predicate<bool(*)(int), int> cp(is5);
assert(!cp(6));
assert(cp.count() == 1);
assert(call_pred(cp));
assert(cp.count() == 1);
assert(call_pred(std::ref(cp)));
assert(cp.count() == 2);
}
return 0;
}
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