ext-boost/boost/icl/detail/on_absorbtion.hpp
2016-03-02 00:27:27 -05:00

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/*-----------------------------------------------------------------------------+
Copyright (c) 2010-2010: Joachim Faulhaber
+------------------------------------------------------------------------------+
Distributed under the Boost Software License, Version 1.0.
(See accompanying file LICENCE.txt or copy at
http://www.boost.org/LICENSE_1_0.txt)
+-----------------------------------------------------------------------------*/
#ifndef BOOST_ICL_TYPE_TRAITS_ON_ABSORBTION_HPP_JOFA_100915
#define BOOST_ICL_TYPE_TRAITS_ON_ABSORBTION_HPP_JOFA_100915
namespace boost{ namespace icl
{
template<class Type, class Combiner, bool absorbs_identities>
struct on_absorbtion;
template<class Type, class Combiner>
struct on_absorbtion<Type, Combiner, false>
{
typedef on_absorbtion type;
typedef typename Type::codomain_type codomain_type;
static bool is_absorbable(const codomain_type&){ return false; }
};
template<class Type, class Combiner>
struct on_absorbtion<Type, Combiner, true>
{
typedef on_absorbtion type;
typedef typename Type::codomain_type codomain_type;
typedef typename Type::codomain_combine codomain_combine;
static bool is_absorbable(const codomain_type& co_value)
{
return co_value == Combiner::identity_element();
}
};
}} // namespace boost icl
#endif