ecency-mobile/ios/Pods/boost-for-react-native/boost/hana/pair.hpp

148 lines
5.4 KiB
C++

/*!
@file
Defines `boost::hana::pair`.
@copyright Louis Dionne 2013-2016
Distributed under the Boost Software License, Version 1.0.
(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
*/
#ifndef BOOST_HANA_PAIR_HPP
#define BOOST_HANA_PAIR_HPP
#include <boost/hana/fwd/pair.hpp>
#include <boost/hana/basic_tuple.hpp>
#include <boost/hana/config.hpp>
#include <boost/hana/detail/decay.hpp>
#include <boost/hana/detail/intrinsics.hpp>
#include <boost/hana/detail/operators/adl.hpp>
#include <boost/hana/detail/operators/comparable.hpp>
#include <boost/hana/detail/operators/orderable.hpp>
#include <boost/hana/fwd/core/make.hpp>
#include <boost/hana/fwd/first.hpp>
#include <boost/hana/fwd/second.hpp>
#include <type_traits>
#include <utility>
BOOST_HANA_NAMESPACE_BEGIN
//////////////////////////////////////////////////////////////////////////
// pair
//////////////////////////////////////////////////////////////////////////
//! @cond
template <typename First, typename Second>
struct pair : detail::operators::adl<pair<First, Second>> {
template <typename ...dummy, typename = typename std::enable_if<
BOOST_HANA_TT_IS_CONSTRUCTIBLE(First, dummy...) &&
BOOST_HANA_TT_IS_CONSTRUCTIBLE(Second, dummy...)
>::type>
constexpr pair()
: storage_()
{ }
template <typename ...dummy, typename = typename std::enable_if<
BOOST_HANA_TT_IS_CONSTRUCTIBLE(First, First const&, dummy...) &&
BOOST_HANA_TT_IS_CONSTRUCTIBLE(Second, Second const&, dummy...)
>::type>
constexpr pair(First const& first, Second const& second)
: storage_{first, second}
{ }
template <typename T, typename U, typename = typename std::enable_if<
BOOST_HANA_TT_IS_CONVERTIBLE(T&&, First) &&
BOOST_HANA_TT_IS_CONVERTIBLE(U&&, Second)
>::type>
constexpr pair(T&& t, U&& u)
: storage_{static_cast<T&&>(t), static_cast<U&&>(u)}
{ }
template <typename T, typename U, typename = typename std::enable_if<
BOOST_HANA_TT_IS_CONVERTIBLE(T const&, First) &&
BOOST_HANA_TT_IS_CONVERTIBLE(U const&, Second)
>::type>
constexpr pair(pair<T, U> const& other)
: storage_{hana::get_impl<0>(other.storage_),
hana::get_impl<1>(other.storage_)}
{ }
template <typename T, typename U, typename = typename std::enable_if<
BOOST_HANA_TT_IS_CONVERTIBLE(T&&, First) &&
BOOST_HANA_TT_IS_CONVERTIBLE(U&&, Second)
>::type>
constexpr pair(pair<T, U>&& other)
: storage_{static_cast<T&&>(hana::get_impl<0>(other.storage_)),
static_cast<U&&>(hana::get_impl<1>(other.storage_))}
{ }
template <typename T, typename U, typename = typename std::enable_if<
BOOST_HANA_TT_IS_ASSIGNABLE(First&, T const&) &&
BOOST_HANA_TT_IS_ASSIGNABLE(Second&, U const&)
>::type>
constexpr pair& operator=(pair<T, U> const& other) {
hana::get_impl<0>(storage_) = hana::get_impl<0>(other.storage_);
hana::get_impl<1>(storage_) = hana::get_impl<1>(other.storage_);
return *this;
}
template <typename T, typename U, typename = typename std::enable_if<
BOOST_HANA_TT_IS_ASSIGNABLE(First&, T&&) &&
BOOST_HANA_TT_IS_ASSIGNABLE(Second&, U&&)
>::type>
constexpr pair& operator=(pair<T, U>&& other) {
hana::get_impl<0>(storage_) = static_cast<T&&>(hana::get_impl<0>(other.storage_));
hana::get_impl<1>(storage_) = static_cast<U&&>(hana::get_impl<1>(other.storage_));
return *this;
}
using hana_tag = pair_tag;
basic_tuple<First, Second> storage_;
};
//! @endcond
//////////////////////////////////////////////////////////////////////////
// Operators
//////////////////////////////////////////////////////////////////////////
namespace detail {
template <>
struct comparable_operators<pair_tag> {
static constexpr bool value = true;
};
template <>
struct orderable_operators<pair_tag> {
static constexpr bool value = true;
};
}
//////////////////////////////////////////////////////////////////////////
// Product
//////////////////////////////////////////////////////////////////////////
template <>
struct make_impl<pair_tag> {
template <typename F, typename S>
static constexpr pair<
typename detail::decay<F>::type,
typename detail::decay<S>::type
> apply(F&& f, S&& s) {
return {static_cast<F&&>(f), static_cast<S&&>(s)};
}
};
template <>
struct first_impl<pair_tag> {
template <typename P>
static constexpr decltype(auto) apply(P&& p)
{ return hana::get_impl<0>(static_cast<P&&>(p).storage_); }
};
template <>
struct second_impl<pair_tag> {
template <typename P>
static constexpr decltype(auto) apply(P&& p)
{ return hana::get_impl<1>(static_cast<P&&>(p).storage_); }
};
BOOST_HANA_NAMESPACE_END
#endif // !BOOST_HANA_PAIR_HPP