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

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1.5 KiB
C++

/*!
@file
Defines `boost::hana::accessors`.
@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_ACCESSORS_HPP
#define BOOST_HANA_ACCESSORS_HPP
#include <boost/hana/fwd/accessors.hpp>
#include <boost/hana/concept/struct.hpp>
#include <boost/hana/config.hpp>
#include <boost/hana/core/dispatch.hpp>
BOOST_HANA_NAMESPACE_BEGIN
template <typename S>
struct accessors_t {
#ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
static_assert(hana::Struct<S>::value,
"hana::accessors<S> requires 'S' to be a Struct");
#endif
constexpr decltype(auto) operator()() const {
using Accessors = BOOST_HANA_DISPATCH_IF(accessors_impl<S>,
hana::Struct<S>::value
);
return Accessors::apply();
}
};
template <typename S, bool condition>
struct accessors_impl<S, when<condition>> : default_ {
template <typename ...Args>
static constexpr auto apply(Args&& ...) = delete;
};
namespace struct_detail {
template <typename ...>
struct is_valid { static constexpr bool value = true; };
}
template <typename S>
struct accessors_impl<S, when<
struct_detail::is_valid<typename S::hana_accessors_impl>::value
>>
: S::hana_accessors_impl
{ };
BOOST_HANA_NAMESPACE_END
#endif // !BOOST_HANA_ACCESSORS_HPP