mirror of
https://github.com/ecency/ecency-mobile.git
synced 2024-12-04 17:33:55 +03:00
62 lines
1.9 KiB
C++
62 lines
1.9 KiB
C++
/*!
|
|
@file
|
|
Defines `boost::hana::or_`.
|
|
|
|
@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_OR_HPP
|
|
#define BOOST_HANA_OR_HPP
|
|
|
|
#include <boost/hana/fwd/or.hpp>
|
|
|
|
#include <boost/hana/concept/logical.hpp>
|
|
#include <boost/hana/config.hpp>
|
|
#include <boost/hana/core/dispatch.hpp>
|
|
#include <boost/hana/detail/variadic/foldl1.hpp>
|
|
#include <boost/hana/if.hpp>
|
|
|
|
|
|
BOOST_HANA_NAMESPACE_BEGIN
|
|
//! @cond
|
|
template <typename X, typename Y>
|
|
constexpr decltype(auto) or_t::operator()(X&& x, Y&& y) const {
|
|
using Bool = typename hana::tag_of<X>::type;
|
|
using Or = BOOST_HANA_DISPATCH_IF(or_impl<Bool>,
|
|
hana::Logical<Bool>::value
|
|
);
|
|
|
|
#ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
|
|
static_assert(hana::Logical<Bool>::value,
|
|
"hana::or_(x, y) requires 'x' to be a Logical");
|
|
#endif
|
|
|
|
return Or::apply(static_cast<X&&>(x), static_cast<Y&&>(y));
|
|
}
|
|
|
|
template <typename X, typename ...Y>
|
|
constexpr decltype(auto) or_t::operator()(X&& x, Y&& ...y) const {
|
|
return detail::variadic::foldl1(
|
|
*this,
|
|
static_cast<X&&>(x),
|
|
static_cast<Y&&>(y)...
|
|
);
|
|
}
|
|
//! @endcond
|
|
|
|
template <typename L, bool condition>
|
|
struct or_impl<L, when<condition>> : hana::default_ {
|
|
template <typename X, typename Y>
|
|
static constexpr decltype(auto) apply(X&& x, Y&& y) {
|
|
//! @todo How to forward `x` here? Since the arguments to `if_`
|
|
//! can be evaluated in any order, we have to be careful not to
|
|
//! use `x` in a moved-from state.
|
|
return hana::if_(x, x, static_cast<Y&&>(y));
|
|
}
|
|
};
|
|
BOOST_HANA_NAMESPACE_END
|
|
|
|
#endif // !BOOST_HANA_OR_HPP
|