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// Copyright 2019 Peter Dimov.
//
// Distributed under the Boost Software License, Version 1.0.
//
// See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt
#include <boost/mp11/utility.hpp>
#include <boost/core/lightweight_test_trait.hpp>
#include <cstddef>
template<class T> using difference_type = typename T::difference_type;
struct X
{
};
struct Y
{
using difference_type = int;
};
int main()
{
using boost::mp11::mp_eval_or;
using boost::mp11::mp_eval_or_q;
using boost::mp11::mp_identity;
using boost::mp11::mp_quote;
BOOST_TEST_TRAIT_SAME(mp_eval_or<void, mp_identity>, void);
BOOST_TEST_TRAIT_SAME(mp_eval_or<void, mp_identity, int>, mp_identity<int>);
BOOST_TEST_TRAIT_SAME(mp_eval_or<void, mp_identity, int, int>, void);
using Q_identity = mp_quote<mp_identity>;
BOOST_TEST_TRAIT_SAME(mp_eval_or_q<void, Q_identity>, void);
BOOST_TEST_TRAIT_SAME(mp_eval_or_q<void, Q_identity, int>, mp_identity<int>);
BOOST_TEST_TRAIT_SAME(mp_eval_or_q<void, Q_identity, int, int>, void);
BOOST_TEST_TRAIT_SAME(mp_eval_or<std::ptrdiff_t, difference_type, X>, std::ptrdiff_t);
BOOST_TEST_TRAIT_SAME(mp_eval_or<std::ptrdiff_t, difference_type, Y>, int);
using Q_diff_type = mp_quote<difference_type>;
BOOST_TEST_TRAIT_SAME(mp_eval_or_q<std::ptrdiff_t, Q_diff_type, X>, std::ptrdiff_t);
BOOST_TEST_TRAIT_SAME(mp_eval_or_q<std::ptrdiff_t, Q_diff_type, Y>, int);
return boost::report_errors();
}
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