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- /*!
- @file
- Defines `boost::hana::and_`.
- @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)
- */
- #ifndef BOOST_HANA_AND_HPP
- #define BOOST_HANA_AND_HPP
- #include <boost/hana/fwd/and.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) and_t::operator()(X&& x, Y&& y) const {
- using Bool = typename hana::tag_of<X>::type;
- using And = BOOST_HANA_DISPATCH_IF(and_impl<Bool>,
- hana::Logical<Bool>::value
- );
- #ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
- static_assert(hana::Logical<Bool>::value,
- "hana::and_(x, y) requires 'x' to be a Logical");
- #endif
- return And::apply(static_cast<X&&>(x), static_cast<Y&&>(y));
- }
- template <typename X, typename ...Y>
- constexpr decltype(auto) and_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 and_impl<L, when<condition>> : default_ {
- template <typename X, typename Y>
- static constexpr decltype(auto) apply(X&& x, Y&& y) {
- return hana::if_(x, static_cast<Y&&>(y), x);
- }
- };
- BOOST_HANA_NAMESPACE_END
- #endif // !BOOST_HANA_AND_HPP
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