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// Copyright Jason Rice 2016
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
#include <boost/hana/assert.hpp>
#include <boost/hana/at_key.hpp>
#include <boost/hana/core/to.hpp>
#include <boost/hana/equal.hpp>
#include <boost/hana/hash.hpp>
#include <boost/hana/integral_constant.hpp>
#include <boost/hana/map.hpp>
#include <boost/hana/not.hpp>
#include <boost/hana/pair.hpp>
#include <boost/hana/tuple.hpp>
namespace hana = boost::hana;
struct A { };
struct B { };
struct the_hash;
namespace boost { namespace hana {
template <>
struct hash_impl<A> {
static constexpr auto apply(A const&) {
return hana::type_c<the_hash>;
}
};
template <>
struct hash_impl<B> {
static constexpr auto apply(B const&) {
return hana::type_c<the_hash>;
}
};
template <>
struct equal_impl<A, A> {
static constexpr auto apply(A const&, A const&) {
return hana::true_c;
}
};
template <>
struct equal_impl<B, B> {
static constexpr auto apply(B const&, B const&) {
return hana::true_c;
}
};
}}
int main() {
constexpr auto key1 = A{};
constexpr auto key2 = B{};
BOOST_HANA_CONSTANT_CHECK(hana::equal(key1, key1));
BOOST_HANA_CONSTANT_CHECK(hana::equal(key2, key2));
BOOST_HANA_CONSTANT_CHECK(hana::not_(hana::equal(key1, key2)));
// ensure the hashes actually collide
BOOST_HANA_CONSTANT_CHECK(hana::equal(hana::hash(key1), hana::hash(key2)));
{
auto map = hana::to_map(hana::make_tuple(
hana::make_pair(key1, key1),
hana::make_pair(key2, key2)
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::at_key(map, key1),
key1
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::at_key(map, key2),
key2
));
}
{
auto map = hana::to_map(hana::make_tuple(
hana::make_pair(key2, key2),
hana::make_pair(key1, key1)
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::at_key(map, key1),
key1
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::at_key(map, key2),
key2
));
}
{
auto map = hana::to_map(hana::make_tuple(
hana::make_pair(key1, key1),
hana::make_pair(hana::int_c<56>, hana::int_c<56>),
hana::make_pair(key2, key2)
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::at_key(map, key1),
key1
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::at_key(map, hana::int_c<56>),
hana::int_c<56>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::at_key(map, key2),
key2
));
}
{
auto map = hana::to_map(hana::make_tuple(
hana::make_pair(key1, key1),
hana::make_pair(hana::int_c<56>, hana::int_c<56>),
hana::make_pair(key2, key2),
hana::make_pair(hana::int_c<42>, hana::int_c<42>)
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::at_key(map, key1),
key1
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::at_key(map, hana::int_c<56>),
hana::int_c<56>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::at_key(map, key2),
key2
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::at_key(map, hana::int_c<42>),
hana::int_c<42>
));
}
}
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