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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <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 <cmath>
template <class T>
void
test()
{
static_assert((std::is_base_of<std::unary_function<T, std::size_t>,
std::hash<T> >::value), "");
std::hash<T> h;
std::size_t t0 = h(0.);
std::size_t tn0 = h(-0.);
std::size_t tp1 = h(0.1);
std::size_t t1 = h(1);
std::size_t tn1 = h(-1);
std::size_t pinf = h(INFINITY);
std::size_t ninf = h(-INFINITY);
assert(t0 == tn0);
assert(t0 != tp1);
assert(t0 != t1);
assert(t0 != tn1);
assert(t0 != pinf);
assert(t0 != ninf);
assert(tp1 != t1);
assert(tp1 != tn1);
assert(tp1 != pinf);
assert(tp1 != ninf);
assert(t1 != tn1);
assert(t1 != pinf);
assert(t1 != ninf);
assert(tn1 != pinf);
assert(tn1 != ninf);
assert(pinf != ninf);
}
int main()
{
test<float>();
test<double>();
test<long double>();
}
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