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34 lines
926 B
C++
34 lines
926 B
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
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* http://www.boost.org/LICENSE_1_0.txt)
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*/
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#include <boost/hana/logical.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/type.hpp>
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#include <type_traits>
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using namespace boost::hana;
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struct T { };
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struct E { };
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template <bool Cond>
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struct pick_type {
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static constexpr auto value_t = if_(bool_<Cond>, type<T>, type<E>);
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typename decltype(value_t)::type value;
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};
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int main() {
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BOOST_HANA_STATIC_ASSERT(if_(true_, int_<0>, int_<1>) == int_<0>);
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BOOST_HANA_STATIC_ASSERT(if_(false_, int_<0>, int_<1>) == int_<1>);
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static_assert(std::is_same<decltype(pick_type<true>{}.value), T>::value, "");
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static_assert(std::is_same<decltype(pick_type<false>{}.value), E>::value, "");
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}
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