1 //

     2 //=======================================================================

     3 // Copyright 1997, 1998, 1999, 2000 University of Notre Dame.

     4 // Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek

     5 //

     6 // Distributed under the Boost Software License, Version 1.0. (See

     7 // accompanying file LICENSE_1_0.txt or copy at

     8 // http://www.boost.org/LICENSE_1_0.txt)

     9 //=======================================================================

    10 //

    11 

    12 #ifndef BOOST_INDIRECT_CMP_HPP

    13 #define BOOST_INDIRECT_CMP_HPP

    14 

    15 #include <functional>

    16 #include <boost/config.hpp>

    17 #include <boost/property_map.hpp>

    18 

    19 namespace boost {

    20 

    21   //: indirect_cmp

    22   //

    23   // could also do this with compose_f_gx_hx, and the member binder...

    24   //

    25   //!category: functors

    26   //!component: type

    27   //!tparam: ReadablePropertyMap - a model of ReadablePropertyMap

    28   //!definition: functor.h

    29   template <class ReadablePropertyMap, class Compare>

    30   class indirect_cmp {

    31   public:

    32     typedef typename boost::property_traits<ReadablePropertyMap>::value_type T;

    33     typedef typename boost::property_traits<ReadablePropertyMap>::key_type K;

    34     typedef K first_argument_type;

    35     typedef K second_argument_type;

    36     typedef T result_type;

    37     inline indirect_cmp(const ReadablePropertyMap& df, const Compare& c = Compare())

    38       : d(df), cmp(c) { }

    39 

    40     template <class A, class B>

    41     inline bool 

    42     operator()(const A& u, const B& v) const {

    43       T du = get(d, u), dv = get(d, v);

    44       return cmp(du, dv);

    45     }

    46   protected:

    47     ReadablePropertyMap d;

    48     Compare cmp;

    49   };

    50 

    51   template <typename Compare, typename ReadablePropertyMap>

    52   indirect_cmp<ReadablePropertyMap, Compare>

    53   make_indirect_cmp(const Compare& cmp, ReadablePropertyMap pmap) {

    54     indirect_cmp<ReadablePropertyMap, Compare> p(pmap, cmp);

    55     return p;

    56   }

    57 

    58   template <class ReadablePropertyMap>

    59   class indirect_pmap {

    60   public:

    61     typedef typename boost::property_traits<ReadablePropertyMap>::value_type T;

    62     typedef typename boost::property_traits<ReadablePropertyMap>::key_type K;

    63     typedef K argument_type;

    64     typedef T result_type;

    65     inline indirect_pmap(const ReadablePropertyMap& df)

    66       : d(df) { }

    67 

    68     inline bool operator()(const K& u) const {

    69       return get(d, u);

    70     }

    71   protected:

    72     ReadablePropertyMap d;

    73   };

    74 

    75   template <typename ReadablePropertyMap>

    76   indirect_pmap<ReadablePropertyMap>

    77   make_indirect_pmap(ReadablePropertyMap pmap) {

    78     indirect_pmap<ReadablePropertyMap> f(pmap);

    79     return f;

    80   }

    81 

    82 

    83 } // namespace boost

    84 

    85 

    86 #endif // GGCL_INDIRECT_CMP_HPP