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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>
// template <class T>
// struct hash
// : public unary_function<T, size_t>
// {
// size_t operator()(T val) const;
// };
// Not very portable
#include <functional>
#include <cassert>
#include <type_traits>
#include <limits>
#include "test_macros.h"
template <class T>
void
test()
{
typedef std::hash<T> H;
static_assert((std::is_same<typename H::argument_type, T>::value), "" );
static_assert((std::is_same<typename H::result_type, std::size_t>::value), "" );
ASSERT_NOEXCEPT(H()(T()));
H h;
typedef typename std::remove_pointer<T>::type type;
type i;
type j;
assert(h(&i) != h(&j));
}
// can't hash nullptr_t until C++17
void test_nullptr()
{
#if TEST_STD_VER > 14
typedef std::nullptr_t T;
typedef std::hash<T> H;
static_assert((std::is_same<typename H::argument_type, T>::value), "" );
static_assert((std::is_same<typename H::result_type, std::size_t>::value), "" );
ASSERT_NOEXCEPT(H()(T()));
#endif
}
int main(int, char**)
{
test<int*>();
test_nullptr();
return 0;
}
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