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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/bool.hpp>
#include <boost/hana/fwd/hash.hpp>
#include <boost/hana/set.hpp>
#include <boost/hana/type.hpp>
#include <type_traits>
namespace hana = boost::hana;
template <int i>
struct NoDefault {
NoDefault() = delete;
NoDefault(NoDefault const&) = default;
constexpr explicit NoDefault(int) { }
};
template <int i, int j>
auto operator==(NoDefault<i> const&, NoDefault<j> const&) { return hana::bool_<i == j>{}; }
template <int i, int j>
auto operator!=(NoDefault<i> const&, NoDefault<j> const&) { return hana::bool_<i != j>{}; }
template <int i>
struct Default {
Default() = default;
Default(Default const&) = default;
constexpr explicit Default(int) { }
};
template <int i, int j>
auto operator==(Default<i> const&, Default<j> const&) { return hana::bool_<i == j>{}; }
template <int i, int j>
auto operator!=(Default<i> const&, Default<j> const&) { return hana::bool_<i != j>{}; }
namespace boost { namespace hana {
template <int i>
struct hash_impl<NoDefault<i>> {
static constexpr auto apply(NoDefault<i> const&)
{ return hana::type_c<NoDefault<i>>; };
};
template <int i>
struct hash_impl<Default<i>> {
static constexpr auto apply(Default<i> const&)
{ return hana::type_c<Default<i>>; };
};
}}
int main() {
{
auto set0 = hana::make_set();
static_assert(std::is_default_constructible<decltype(set0)>{}, "");
auto set1 = hana::make_set(Default<0>(int{}));
static_assert(std::is_default_constructible<decltype(set1)>{}, "");
auto set2 = hana::make_set(Default<0>(int{}), Default<1>(int{}));
static_assert(std::is_default_constructible<decltype(set2)>{}, "");
auto set3 = hana::make_set(Default<0>(int{}), NoDefault<1>(int{}), Default<2>(int{}));
static_assert(!std::is_default_constructible<decltype(set3)>{}, "");
}
{
auto set1 = hana::make_set(NoDefault<0>(int{}));
static_assert(!std::is_default_constructible<decltype(set1)>{}, "");
auto set2 = hana::make_set(NoDefault<0>(int{}), NoDefault<1>(int{}));
static_assert(!std::is_default_constructible<decltype(set2)>{}, "");
auto set3 = hana::make_set(NoDefault<0>(int{}), NoDefault<1>(int{}), NoDefault<2>(int{}));
static_assert(!std::is_default_constructible<decltype(set3)>{}, "");
}
}
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