35 lines
997 B
C++
35 lines
997 B
C++
|
/*!
|
||
|
@file
|
||
|
Defines `boost::hana::Monoid`.
|
||
|
|
||
|
@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_CONCEPT_MONOID_HPP
|
||
|
#define BOOST_HANA_CONCEPT_MONOID_HPP
|
||
|
|
||
|
#include <boost/hana/fwd/concept/monoid.hpp>
|
||
|
|
||
|
#include <boost/hana/config.hpp>
|
||
|
#include <boost/hana/core/default.hpp>
|
||
|
#include <boost/hana/core/tag_of.hpp>
|
||
|
#include <boost/hana/detail/integral_constant.hpp>
|
||
|
#include <boost/hana/plus.hpp>
|
||
|
#include <boost/hana/zero.hpp>
|
||
|
|
||
|
|
||
|
BOOST_HANA_NAMESPACE_BEGIN
|
||
|
template <typename M>
|
||
|
struct Monoid
|
||
|
: hana::integral_constant<bool,
|
||
|
!is_default<zero_impl<typename tag_of<M>::type>>::value &&
|
||
|
!is_default<plus_impl<typename tag_of<M>::type,
|
||
|
typename tag_of<M>::type>>::value
|
||
|
>
|
||
|
{ };
|
||
|
BOOST_HANA_NAMESPACE_END
|
||
|
|
||
|
#endif // !BOOST_HANA_CONCEPT_MONOID_HPP
|