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// Copyright Louis Dionne 2013-2017
// 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/config.hpp>
#include <boost/hana/core/to.hpp>
#include <boost/hana/equal.hpp>
#include <boost/hana/tuple.hpp>
namespace hana = boost::hana;
template <typename X, typename Y, typename Z>
struct Triple {
X first;
Y second;
Z third;
};
BOOST_HANA_CONSTEXPR_LAMBDA auto triple = [](auto x, auto y, auto z) {
return Triple<decltype(x), decltype(y), decltype(z)>{x, y, z};
};
namespace boost { namespace hana {
template <typename X, typename Y, typename Z>
struct to_impl<tuple_tag, Triple<X, Y, Z>> {
static constexpr auto apply(Triple<X, Y, Z> xs) {
return make_tuple(xs.first, xs.second, xs.third);
}
};
}}
int main() {
BOOST_HANA_CONSTEXPR_CHECK(
hana::to<hana::tuple_tag>(triple(1, '2', 3.3)) == hana::make_tuple(1, '2', 3.3)
);
}
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