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// Copyright 2005 Daniel James.
// Copyright 2022 Peter Dimov.
// Distributed under the Boost Software License, Version 1.0.
// https://www.boost.org/LICENSE_1_0.txt
// Force use of assert.
#if defined(NDEBUG)
#undef NDEBUG
#endif
#include <boost/container_hash/hash.hpp>
#include <boost/describe/class.hpp>
#include <boost/describe/operators.hpp>
#include <cassert>
// This example illustrates how to use Boost.Describe to obtain
// automatic boost::hash support. For full details see the hash
// tutorial.
#if defined(BOOST_DESCRIBE_CXX14)
class point
{
int x;
int y;
BOOST_DESCRIBE_CLASS(point, (), (), (), (x, y))
public:
point() : x(0), y(0) {}
point(int x, int y) : x(x), y(y) {}
};
using boost::describe::operators::operator==;
using boost::describe::operators::operator!=;
int main()
{
boost::hash<point> point_hasher;
point p1(0, 0);
point p2(1, 2);
point p3(4, 1);
point p4 = p1;
assert(point_hasher(p1) == point_hasher(p4));
// These tests could legally fail, but if they did it'd be a pretty bad
// hash function.
assert(point_hasher(p1) != point_hasher(p2));
assert(point_hasher(p1) != point_hasher(p3));
}
#else
#include <cstdio>
int main()
{
std::puts( "This example requires C++14." );
}
#endif
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