source: downloads/boost_1_34_1/boost/property_map.hpp @ 35

//  (C) Copyright Jeremy Siek 1999-2001.
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)

//  See http://www.boost.org/libs/property_map for documentation.

#ifndef BOOST_PROPERTY_MAP_HPP
#define BOOST_PROPERTY_MAP_HPP

#include <cassert>
#include <boost/config.hpp>
#include <boost/pending/cstddef.hpp>
#include <boost/detail/iterator.hpp>
#include <boost/concept_check.hpp>
#include <boost/concept_archetype.hpp>

namespace boost {

  //=========================================================================
  // property_traits class

  template <typename PA>
  struct property_traits {
    typedef typename PA::key_type key_type;
    typedef typename PA::value_type value_type; 
    typedef typename PA::reference reference;
    typedef typename PA::category   category;
  };

  //=========================================================================
  // property_traits category tags

  namespace detail {
    enum ePropertyMapID { READABLE_PA, WRITABLE_PA, 
                          READ_WRITE_PA, LVALUE_PA, OP_BRACKET_PA, 
                          RAND_ACCESS_ITER_PA, LAST_PA };
  }
  struct readable_property_map_tag { enum { id = detail::READABLE_PA }; };
  struct writable_property_map_tag { enum { id = detail::WRITABLE_PA }; };
  struct read_write_property_map_tag :
    public readable_property_map_tag,
    public writable_property_map_tag
  { enum { id = detail::READ_WRITE_PA }; };

  struct lvalue_property_map_tag : public read_write_property_map_tag
  { enum { id = detail::LVALUE_PA }; };

  //=========================================================================
  // property_traits specialization for pointers

#ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
  // The user will just have to create their own specializations for
  // other pointers types if the compiler does not have partial
  // specializations. Sorry!
#define BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(TYPE) \
  template <> \
  struct property_traits<TYPE*> { \
    typedef TYPE value_type; \
    typedef value_type& reference; \
    typedef std::ptrdiff_t key_type; \
    typedef lvalue_property_map_tag   category; \
  }; \
  template <> \
  struct property_traits<const TYPE*> { \
    typedef TYPE value_type; \
    typedef const value_type& reference; \
    typedef std::ptrdiff_t key_type; \
    typedef lvalue_property_map_tag   category; \
  }

  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(long);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(unsigned long);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(int);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(unsigned int);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(short);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(unsigned short);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(char);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(unsigned char);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(signed char);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(bool);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(float);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(double);
  BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(long double);

  // This may need to be turned off for some older compilers that don't have
  // wchar_t intrinsically.
# ifndef BOOST_NO_INTRINSIC_WCHAR_T
  template <>
  struct property_traits<wchar_t*> {
    typedef wchar_t value_type;
    typedef value_type& reference;
    typedef std::ptrdiff_t key_type;
    typedef lvalue_property_map_tag   category;
  };
  template <>
  struct property_traits<const wchar_t*> {
    typedef wchar_t value_type;
    typedef const value_type& reference;
    typedef std::ptrdiff_t key_type;
    typedef lvalue_property_map_tag   category;
  };
# endif

#else
  template <class T>
  struct property_traits<T*> {
    typedef T value_type;
    typedef value_type& reference;
    typedef std::ptrdiff_t key_type;
    typedef lvalue_property_map_tag category;
  };
  template <class T>
  struct property_traits<const T*> {
    typedef T value_type;
    typedef const value_type& reference;
    typedef std::ptrdiff_t key_type;
    typedef lvalue_property_map_tag category;
  };
#endif

#if !defined(BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP)
  // MSVC doesn't have Koenig lookup, so the user has to
  // do boost::get() anyways, and the using clause
  // doesn't really work for MSVC.
} // namespace boost
#endif

  // These need to go in global namespace because Koenig
  // lookup does not apply to T*.

  // V must be convertible to T
  template <class T, class V>
  inline void put(T* pa, std::ptrdiff_t k, const V& val) { pa[k] = val;  }

  template <class T>
  inline const T& get(const T* pa, std::ptrdiff_t k) { return pa[k]; }

#if !defined(BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP)
namespace boost {
  using ::put;
  using ::get;
#endif

  //=========================================================================
  // concept checks for property maps

  template <class PMap, class Key>
  struct ReadablePropertyMapConcept
  {
    typedef typename property_traits<PMap>::key_type key_type;
    typedef typename property_traits<PMap>::reference reference;
    typedef typename property_traits<PMap>::category Category;
    typedef boost::readable_property_map_tag ReadableTag;
    void constraints() {
      function_requires< ConvertibleConcept<Category, ReadableTag> >();

      val = get(pmap, k);
    }
    PMap pmap;
    Key k;
    typename property_traits<PMap>::value_type val;
  };
  template <typename KeyArchetype, typename ValueArchetype>
  struct readable_property_map_archetype {
    typedef KeyArchetype key_type;
    typedef ValueArchetype value_type;
    typedef convertible_to_archetype<ValueArchetype> reference;
    typedef readable_property_map_tag category;
  };
  template <typename K, typename V>
  const typename readable_property_map_archetype<K,V>::reference&
  get(const readable_property_map_archetype<K,V>&, 
      const typename readable_property_map_archetype<K,V>::key_type&)
  {
    typedef typename readable_property_map_archetype<K,V>::reference R;
    return static_object<R>::get();
  }


  template <class PMap, class Key>
  struct WritablePropertyMapConcept
  {
    typedef typename property_traits<PMap>::key_type key_type;
    typedef typename property_traits<PMap>::category Category;
    typedef boost::writable_property_map_tag WritableTag;
    void constraints() {
      function_requires< ConvertibleConcept<Category, WritableTag> >();
      put(pmap, k, val);
    }
    PMap pmap;
    Key k;
    typename property_traits<PMap>::value_type val;
  };
  template <typename KeyArchetype, typename ValueArchetype>
  struct writable_property_map_archetype {
    typedef KeyArchetype key_type;
    typedef ValueArchetype value_type;
    typedef void reference;
    typedef writable_property_map_tag category;
  };
  template <typename K, typename V>
  void put(const writable_property_map_archetype<K,V>&, 
           const typename writable_property_map_archetype<K,V>::key_type&, 
           const typename writable_property_map_archetype<K,V>::value_type&) { }


  template <class PMap, class Key>
  struct ReadWritePropertyMapConcept
  {
    typedef typename property_traits<PMap>::category Category;
    typedef boost::read_write_property_map_tag ReadWriteTag;
    void constraints() {
      function_requires< ReadablePropertyMapConcept<PMap, Key> >();
      function_requires< WritablePropertyMapConcept<PMap, Key> >();
      function_requires< ConvertibleConcept<Category, ReadWriteTag> >();
    }
  };
  template <typename KeyArchetype, typename ValueArchetype>
  struct read_write_property_map_archetype
    : public readable_property_map_archetype<KeyArchetype, ValueArchetype>,
      public writable_property_map_archetype<KeyArchetype, ValueArchetype>
  {
    typedef KeyArchetype key_type;
    typedef ValueArchetype value_type;
    typedef convertible_to_archetype<ValueArchetype> reference;
    typedef read_write_property_map_tag category;
  };


  template <class PMap, class Key>
  struct LvaluePropertyMapConcept
  {
    typedef typename property_traits<PMap>::category Category;
    typedef boost::lvalue_property_map_tag LvalueTag;
    typedef typename property_traits<PMap>::reference reference;

    void constraints() {
      function_requires< ReadablePropertyMapConcept<PMap, Key> >();
      function_requires< ConvertibleConcept<Category, LvalueTag> >();

      typedef typename property_traits<PMap>::value_type value_type;
      typedef typename require_same<
        const value_type&, reference>::type req;

      reference ref = pmap[k];
      ignore_unused_variable_warning(ref);
    }
    PMap pmap;
    Key k;
  };
  template <typename KeyArchetype, typename ValueArchetype>
  struct lvalue_property_map_archetype
    : public readable_property_map_archetype<KeyArchetype, ValueArchetype>
  {
    typedef KeyArchetype key_type;
    typedef ValueArchetype value_type;
    typedef const ValueArchetype& reference;
    typedef lvalue_property_map_tag category;
    const value_type& operator[](const key_type&) const {
      return static_object<value_type>::get();
    }
  };

  template <class PMap, class Key>
  struct Mutable_LvaluePropertyMapConcept
  {
    typedef typename property_traits<PMap>::category Category;
    typedef boost::lvalue_property_map_tag LvalueTag;
    typedef typename property_traits<PMap>::reference reference;
    void constraints() { 
      boost::function_requires< ReadWritePropertyMapConcept<PMap, Key> >();
      boost::function_requires<ConvertibleConcept<Category, LvalueTag> >();
      
      typedef typename property_traits<PMap>::value_type value_type;
      typedef typename require_same<
        value_type&,
        reference>::type req;

      reference ref = pmap[k];
      ignore_unused_variable_warning(ref);
    }
    PMap pmap;
    Key k;
  };
  template <typename KeyArchetype, typename ValueArchetype>
  struct mutable_lvalue_property_map_archetype
    : public readable_property_map_archetype<KeyArchetype, ValueArchetype>,
      public writable_property_map_archetype<KeyArchetype, ValueArchetype>
  {
    typedef KeyArchetype key_type;
    typedef ValueArchetype value_type;
    typedef ValueArchetype& reference;
    typedef lvalue_property_map_tag category;
    value_type& operator[](const key_type&) const { 
      return static_object<value_type>::get();
    }
  };

  struct identity_property_map;

  // A helper class for constructing a property map
  // from a class that implements operator[]

  template <class Reference, class LvaluePropertyMap>
  struct put_get_helper { };

  template <class PropertyMap, class Reference, class K>
  inline Reference
  get(const put_get_helper<Reference, PropertyMap>& pa, const K& k)
  {
    Reference v = static_cast<const PropertyMap&>(pa)[k];
    return v;
  }
  template <class PropertyMap, class Reference, class K, class V>
  inline void
  put(const put_get_helper<Reference, PropertyMap>& pa, K k, const V& v)
  {
    static_cast<const PropertyMap&>(pa)[k] = v;
  }

  //=========================================================================
  // Adapter to turn a RandomAccessIterator into a property map

  template <class RandomAccessIterator, 
    class IndexMap
#ifdef BOOST_NO_STD_ITERATOR_TRAITS
    , class T, class R
#else
    , class T = typename std::iterator_traits<RandomAccessIterator>::value_type
    , class R = typename std::iterator_traits<RandomAccessIterator>::reference
#endif
     >
  class iterator_property_map
    : public boost::put_get_helper< R, 
        iterator_property_map<RandomAccessIterator, IndexMap,
        T, R> >
  {
  public:
    typedef typename property_traits<IndexMap>::key_type key_type;
    typedef T value_type;
    typedef R reference;
    typedef boost::lvalue_property_map_tag category;

    inline iterator_property_map(
      RandomAccessIterator cc = RandomAccessIterator(), 
      const IndexMap& _id = IndexMap() ) 
      : iter(cc), index(_id) { }
    inline R operator[](key_type v) const { return *(iter + get(index, v)) ; }
  protected:
    RandomAccessIterator iter;
    IndexMap index;
  };

#if !defined BOOST_NO_STD_ITERATOR_TRAITS
  template <class RAIter, class ID>
  inline iterator_property_map<
    RAIter, ID,
    typename std::iterator_traits<RAIter>::value_type,
    typename std::iterator_traits<RAIter>::reference>
  make_iterator_property_map(RAIter iter, ID id) {
    function_requires< RandomAccessIteratorConcept<RAIter> >();
    typedef iterator_property_map<
      RAIter, ID,
      typename std::iterator_traits<RAIter>::value_type,
      typename std::iterator_traits<RAIter>::reference> PA;
    return PA(iter, id);
  }
#endif
  template <class RAIter, class Value, class ID>
  inline iterator_property_map<RAIter, ID, Value, Value&>
  make_iterator_property_map(RAIter iter, ID id, Value) {
    function_requires< RandomAccessIteratorConcept<RAIter> >();
    typedef iterator_property_map<RAIter, ID, Value, Value&> PMap;
    return PMap(iter, id);
  }

  template <class RandomAccessIterator, 
    class IndexMap
#ifdef BOOST_NO_STD_ITERATOR_TRAITS
    , class T, class R
#else
    , class T = typename std::iterator_traits<RandomAccessIterator>::value_type
    , class R = typename std::iterator_traits<RandomAccessIterator>::reference
#endif
     >
  class safe_iterator_property_map
    : public boost::put_get_helper< R, 
        safe_iterator_property_map<RandomAccessIterator, IndexMap,
        T, R> >
  {
  public:
    typedef typename property_traits<IndexMap>::key_type key_type; 
    typedef T value_type;
    typedef R reference;
    typedef boost::lvalue_property_map_tag category;

    inline safe_iterator_property_map(
      RandomAccessIterator first, 
      std::size_t n_ = 0, 
      const IndexMap& _id = IndexMap() ) 
      : iter(first), n(n_), index(_id) { }
    inline safe_iterator_property_map() { }
    inline R operator[](key_type v) const {
      assert(get(index, v) < n);
      return *(iter + get(index, v)) ;
    }
    typename property_traits<IndexMap>::value_type size() const { return n; }
  protected:
    RandomAccessIterator iter;
    typename property_traits<IndexMap>::value_type n;
    IndexMap index;
  };

#if !defined BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
  template <class RAIter, class ID>
  inline safe_iterator_property_map<
    RAIter, ID,
    typename boost::detail::iterator_traits<RAIter>::value_type,
    typename boost::detail::iterator_traits<RAIter>::reference>
  make_safe_iterator_property_map(RAIter iter, std::size_t n, ID id) {
    function_requires< RandomAccessIteratorConcept<RAIter> >();
    typedef safe_iterator_property_map<
      RAIter, ID,
      typename boost::detail::iterator_traits<RAIter>::value_type,
      typename boost::detail::iterator_traits<RAIter>::reference> PA;
    return PA(iter, n, id);
  }
#endif
  template <class RAIter, class Value, class ID>
  inline safe_iterator_property_map<RAIter, ID, Value, Value&>
  make_safe_iterator_property_map(RAIter iter, std::size_t n, ID id, Value) {
    function_requires< RandomAccessIteratorConcept<RAIter> >();
    typedef safe_iterator_property_map<RAIter, ID, Value, Value&> PMap;
    return PMap(iter, n, id);
  }

  //=========================================================================
  // An adaptor to turn a Unique Pair Associative Container like std::map or
  // std::hash_map into an Lvalue Property Map.

  template <typename UniquePairAssociativeContainer>
  class associative_property_map
    : public boost::put_get_helper<
       typename UniquePairAssociativeContainer::value_type::second_type&,
       associative_property_map<UniquePairAssociativeContainer> >
  {
    typedef UniquePairAssociativeContainer C;
  public:
    typedef typename C::key_type key_type;
    typedef typename C::value_type::second_type value_type;
    typedef value_type& reference;
    typedef lvalue_property_map_tag category;
    associative_property_map() : m_c(0) { }
    associative_property_map(C& c) : m_c(&c) { }
    reference operator[](const key_type& k) const {
      return (*m_c)[k];
    }
  private:
    C* m_c;
  };

  template <class UniquePairAssociativeContainer>
  associative_property_map<UniquePairAssociativeContainer>
  make_assoc_property_map(UniquePairAssociativeContainer& c)
  {
    return associative_property_map<UniquePairAssociativeContainer>(c);
  }

  template <typename UniquePairAssociativeContainer>
  class const_associative_property_map
    : public boost::put_get_helper<
       const typename UniquePairAssociativeContainer::value_type::second_type&,
       const_associative_property_map<UniquePairAssociativeContainer> >
  {
    typedef UniquePairAssociativeContainer C;
  public:
    typedef typename C::key_type key_type;
    typedef typename C::value_type::second_type value_type;
    typedef const value_type& reference;
    typedef lvalue_property_map_tag category;
    const_associative_property_map() : m_c(0) { }
    const_associative_property_map(const C& c) : m_c(&c) { }
    reference operator[](const key_type& k) const {
      return m_c->find(k)->second;
    }
  private:
    C const* m_c;
  };
  
  template <class UniquePairAssociativeContainer>
  const_associative_property_map<UniquePairAssociativeContainer>
  make_assoc_property_map(const UniquePairAssociativeContainer& c)
  {
    return const_associative_property_map<UniquePairAssociativeContainer>(c);
  }

  //=========================================================================
  // A property map that applies the identity function to integers
  struct identity_property_map
    : public boost::put_get_helper<std::size_t, 
        identity_property_map>
  {
    typedef std::size_t key_type;
    typedef std::size_t value_type;
    typedef std::size_t reference;
    typedef boost::readable_property_map_tag category;

    inline value_type operator[](const key_type& v) const { return v; }
  };

  //=========================================================================
  // A property map that does not do anything, for
  // when you have to supply a property map, but don't need it.
  namespace detail {
    struct dummy_pmap_reference {
      template <class T>
      dummy_pmap_reference& operator=(const T&) { return *this; }
      operator int() { return 0; }
    };
  }
  class dummy_property_map 
    : public boost::put_get_helper<detail::dummy_pmap_reference,
        dummy_property_map  > 
  {
  public:
    typedef void key_type; 
    typedef int value_type;
    typedef detail::dummy_pmap_reference reference;
    typedef boost::read_write_property_map_tag category;
    inline dummy_property_map() : c(0) { }
    inline dummy_property_map(value_type cc) : c(cc) { }
    inline dummy_property_map(const dummy_property_map& x)
      : c(x.c) { }
    template <class Vertex>
    inline reference operator[](Vertex) const { return reference(); }
   protected:
    value_type c;
  };


} // namespace boost


#endif /* BOOST_PROPERTY_MAP_HPP */