54 lines
1.5 KiB
C++
54 lines
1.5 KiB
C++
|
/*!
|
||
|
|
@file
|
||
|
|
Forward declares `boost::hana::and_`.
|
||
|
|
|
||
|
|
@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_FWD_AND_HPP
|
||
|
|
#define BOOST_HANA_FWD_AND_HPP
|
||
|
|
|
||
|
|
#include <boost/hana/config.hpp>
|
||
|
|
#include <boost/hana/core/when.hpp>
|
||
|
|
|
||
|
|
|
||
|
|
BOOST_HANA_NAMESPACE_BEGIN
|
||
|
|
//! Return whether all the arguments are true-valued.
|
||
|
|
//! @ingroup group-Logical
|
||
|
|
//!
|
||
|
|
//! `and_` can be called with one argument or more. When called with
|
||
|
|
//! two arguments, `and_` uses tag-dispatching to find the right
|
||
|
|
//! implementation. Otherwise,
|
||
|
|
//! @code
|
||
|
|
//! and_(x) == x
|
||
|
|
//! and_(x, y, ...z) == and_(and_(x, y), z...)
|
||
|
|
//! @endcode
|
||
|
|
//!
|
||
|
|
//!
|
||
|
|
//! Example
|
||
|
|
//! -------
|
||
|
|
//! @include example/and.cpp
|
||
|
|
#ifdef BOOST_HANA_DOXYGEN_INVOKED
|
||
|
|
constexpr auto and_ = [](auto&& x, auto&& ...y) -> decltype(auto) {
|
||
|
|
return tag-dispatched;
|
||
|
|
};
|
||
|
|
#else
|
||
|
|
template <typename L, typename = void>
|
||
|
|
struct and_impl : and_impl<L, when<true>> { };
|
||
|
|
|
||
|
|
struct and_t {
|
||
|
|
template <typename X, typename Y>
|
||
|
|
constexpr decltype(auto) operator()(X&& x, Y&& y) const;
|
||
|
|
|
||
|
|
template <typename X, typename ...Y>
|
||
|
|
constexpr decltype(auto) operator()(X&& x, Y&& ...y) const;
|
||
|
|
};
|
||
|
|
|
||
|
|
constexpr and_t and_{};
|
||
|
|
#endif
|
||
|
|
BOOST_HANA_NAMESPACE_END
|
||
|
|
|
||
|
|
#endif // !BOOST_HANA_FWD_AND_HPP
|