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40 lines
1.2 KiB
C++
40 lines
1.2 KiB
C++
/*
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@copyright Louis Dionne 2014
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Distributed under the Boost Software License, Version 1.0.
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(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
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*/
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#include <boost/hana/map.hpp>
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#include <boost/hana/detail/constexpr.hpp>
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#include <boost/hana/detail/static_assert.hpp>
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#include <boost/hana/integral.hpp>
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#include <boost/hana/maybe.hpp>
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#include <boost/hana/pair/instance.hpp>
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using namespace boost::hana;
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template <int i>
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constexpr auto key = int_<i>;
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template <int i>
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constexpr auto value = int_<i + 100>;
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template <int i, int j>
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BOOST_HANA_CONSTEXPR_LAMBDA auto p = pair(key<i>, value<j>);
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BOOST_HANA_CONSTEXPR_LAMBDA auto is = [](auto x) {
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return [=](auto y) { return equal(x, y); };
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};
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int main() {
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BOOST_HANA_STATIC_ASSERT(find(is(key<1>), map()) == nothing);
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BOOST_HANA_STATIC_ASSERT(find(is(key<1>), map(p<1, 1>)) == just(value<1>));
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BOOST_HANA_STATIC_ASSERT(find(is(key<2>), map(p<1, 1>)) == nothing);
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BOOST_HANA_STATIC_ASSERT(find(is(key<1>), map(p<1, 1>, p<2, 2>)) == just(value<1>));
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BOOST_HANA_STATIC_ASSERT(find(is(key<2>), map(p<1, 1>, p<2, 2>)) == just(value<2>));
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BOOST_HANA_STATIC_ASSERT(find(is(key<3>), map(p<1, 1>, p<2, 2>)) == nothing);
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}
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