ceph/src/boost/boost/icl/type_traits/predicate.hpp

   1 /*-----------------------------------------------------------------------------+
   2 Copyright (c) 2010-2010: Joachim Faulhaber
   3 +------------------------------------------------------------------------------+
   4    Distributed under the Boost Software License, Version 1.0.
   5       (See accompanying file LICENCE.txt or copy at
   6            http://www.boost.org/LICENSE_1_0.txt)
   7 +-----------------------------------------------------------------------------*/
   8 #ifndef BOOST_ICL_TYPE_TRAITS_PREDICATE_HPP_JOFA_101102
   9 #define BOOST_ICL_TYPE_TRAITS_PREDICATE_HPP_JOFA_101102
  10
  11 namespace boost{namespace icl
  12 {
  13     // naming convention
  14     // predicate: n-ary predicate
  15     // property:  unary predicate
  16     // relation:  binary predicate
  17
  18     // Unary predicates
  19
  20     template <class Type>
  21     class property
  22     {
  23     public:
  24         typedef Type argument_type;
  25         typedef bool result_type;
  26     };
  27
  28     template <class Type>
  29     class member_property : public property<Type>
  30     {
  31     public:
  32         member_property( bool(Type::* pred)()const ): property<Type>(), m_pred(pred){}
  33         bool operator()(const Type& x)const { return (x.*m_pred)(); }
  34     private:
  35         bool(Type::* m_pred)()const;
  36     } ;
  37
  38     // Binary predicates: relations
  39
  40     template <class LeftT, class RightT>
  41     class relation
  42     {
  43     public:
  44         typedef LeftT first_argument_type;
  45         typedef RightT second_argument_type;
  46         typedef bool result_type;
  47     };
  48
  49
  50 }} // namespace icl boost
  51
  52 #endif
  53