williamr@2: //  (C) Copyright Jeremy Siek 1999-2001.
williamr@2: // Distributed under the Boost Software License, Version 1.0. (See
williamr@2: // accompanying file LICENSE_1_0.txt or copy at
williamr@2: // http://www.boost.org/LICENSE_1_0.txt)
williamr@2: 
williamr@2: //  See http://www.boost.org/libs/property_map for documentation.
williamr@2: 
williamr@2: #ifndef BOOST_PROPERTY_MAP_HPP
williamr@2: #define BOOST_PROPERTY_MAP_HPP
williamr@2: 
williamr@2: #include <cassert>
williamr@2: #include <boost/config.hpp>
williamr@2: #include <boost/pending/cstddef.hpp>
williamr@2: #include <boost/detail/iterator.hpp>
williamr@2: #include <boost/concept_check.hpp>
williamr@2: #include <boost/concept_archetype.hpp>
williamr@2: 
williamr@2: namespace boost {
williamr@2: 
williamr@2:   //=========================================================================
williamr@2:   // property_traits class
williamr@2: 
williamr@2:   template <typename PA>
williamr@2:   struct property_traits {
williamr@2:     typedef typename PA::key_type key_type;
williamr@2:     typedef typename PA::value_type value_type; 
williamr@2:     typedef typename PA::reference reference;
williamr@2:     typedef typename PA::category   category;
williamr@2:   };
williamr@2: 
williamr@2:   //=========================================================================
williamr@2:   // property_traits category tags
williamr@2: 
williamr@2:   namespace detail {
williamr@2:     enum ePropertyMapID { READABLE_PA, WRITABLE_PA, 
williamr@2:                           READ_WRITE_PA, LVALUE_PA, OP_BRACKET_PA, 
williamr@2:                           RAND_ACCESS_ITER_PA, LAST_PA };
williamr@2:   }
williamr@2:   struct readable_property_map_tag { enum { id = detail::READABLE_PA }; };
williamr@2:   struct writable_property_map_tag { enum { id = detail::WRITABLE_PA }; };
williamr@2:   struct read_write_property_map_tag :
williamr@2:     public readable_property_map_tag,
williamr@2:     public writable_property_map_tag
williamr@2:   { enum { id = detail::READ_WRITE_PA }; };
williamr@2: 
williamr@2:   struct lvalue_property_map_tag : public read_write_property_map_tag
williamr@2:   { enum { id = detail::LVALUE_PA }; };
williamr@2: 
williamr@2:   //=========================================================================
williamr@2:   // property_traits specialization for pointers
williamr@2: 
williamr@2: #ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
williamr@2:   // The user will just have to create their own specializations for
williamr@2:   // other pointers types if the compiler does not have partial
williamr@2:   // specializations. Sorry!
williamr@2: #define BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(TYPE) \
williamr@2:   template <> \
williamr@2:   struct property_traits<TYPE*> { \
williamr@2:     typedef TYPE value_type; \
williamr@2:     typedef value_type& reference; \
williamr@2:     typedef std::ptrdiff_t key_type; \
williamr@2:     typedef lvalue_property_map_tag   category; \
williamr@2:   }; \
williamr@2:   template <> \
williamr@2:   struct property_traits<const TYPE*> { \
williamr@2:     typedef TYPE value_type; \
williamr@2:     typedef const value_type& reference; \
williamr@2:     typedef std::ptrdiff_t key_type; \
williamr@2:     typedef lvalue_property_map_tag   category; \
williamr@2:   }
williamr@2: 
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(long);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(unsigned long);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(int);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(unsigned int);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(short);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(unsigned short);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(char);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(unsigned char);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(signed char);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(bool);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(float);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(double);
williamr@2:   BOOST_SPECIALIZE_PROPERTY_TRAITS_PTR(long double);
williamr@2: 
williamr@2:   // This may need to be turned off for some older compilers that don't have
williamr@2:   // wchar_t intrinsically.
williamr@2: # ifndef BOOST_NO_INTRINSIC_WCHAR_T
williamr@2:   template <>
williamr@2:   struct property_traits<wchar_t*> {
williamr@2:     typedef wchar_t value_type;
williamr@2:     typedef value_type& reference;
williamr@2:     typedef std::ptrdiff_t key_type;
williamr@2:     typedef lvalue_property_map_tag   category;
williamr@2:   };
williamr@2:   template <>
williamr@2:   struct property_traits<const wchar_t*> {
williamr@2:     typedef wchar_t value_type;
williamr@2:     typedef const value_type& reference;
williamr@2:     typedef std::ptrdiff_t key_type;
williamr@2:     typedef lvalue_property_map_tag   category;
williamr@2:   };
williamr@2: # endif
williamr@2: 
williamr@2: #else
williamr@2:   template <class T>
williamr@2:   struct property_traits<T*> {
williamr@2:     typedef T value_type;
williamr@2:     typedef value_type& reference;
williamr@2:     typedef std::ptrdiff_t key_type;
williamr@2:     typedef lvalue_property_map_tag category;
williamr@2:   };
williamr@2:   template <class T>
williamr@2:   struct property_traits<const T*> {
williamr@2:     typedef T value_type;
williamr@2:     typedef const value_type& reference;
williamr@2:     typedef std::ptrdiff_t key_type;
williamr@2:     typedef lvalue_property_map_tag category;
williamr@2:   };
williamr@2: #endif
williamr@2: 
williamr@2: #if !defined(BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP)
williamr@2:   // MSVC doesn't have Koenig lookup, so the user has to
williamr@2:   // do boost::get() anyways, and the using clause
williamr@2:   // doesn't really work for MSVC.
williamr@2: } // namespace boost
williamr@2: #endif
williamr@2: 
williamr@2:   // These need to go in global namespace because Koenig
williamr@2:   // lookup does not apply to T*.
williamr@2: 
williamr@2:   // V must be convertible to T
williamr@2:   template <class T, class V>
williamr@2:   inline void put(T* pa, std::ptrdiff_t k, const V& val) { pa[k] = val;  }
williamr@2: 
williamr@2:   template <class T>
williamr@2:   inline const T& get(const T* pa, std::ptrdiff_t k) { return pa[k]; }
williamr@2: 
williamr@2: #if !defined(BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP)
williamr@2: namespace boost {
williamr@2:   using ::put;
williamr@2:   using ::get;
williamr@2: #endif
williamr@2: 
williamr@2:   //=========================================================================
williamr@2:   // concept checks for property maps
williamr@2: 
williamr@2:   template <class PMap, class Key>
williamr@2:   struct ReadablePropertyMapConcept
williamr@2:   {
williamr@2:     typedef typename property_traits<PMap>::key_type key_type;
williamr@2:     typedef typename property_traits<PMap>::reference reference;
williamr@2:     typedef typename property_traits<PMap>::category Category;
williamr@2:     typedef boost::readable_property_map_tag ReadableTag;
williamr@2:     void constraints() {
williamr@2:       function_requires< ConvertibleConcept<Category, ReadableTag> >();
williamr@2: 
williamr@2:       val = get(pmap, k);
williamr@2:     }
williamr@2:     PMap pmap;
williamr@2:     Key k;
williamr@2:     typename property_traits<PMap>::value_type val;
williamr@2:   };
williamr@2:   template <typename KeyArchetype, typename ValueArchetype>
williamr@2:   struct readable_property_map_archetype {
williamr@2:     typedef KeyArchetype key_type;
williamr@2:     typedef ValueArchetype value_type;
williamr@2:     typedef convertible_to_archetype<ValueArchetype> reference;
williamr@2:     typedef readable_property_map_tag category;
williamr@2:   };
williamr@2:   template <typename K, typename V>
williamr@2:   const typename readable_property_map_archetype<K,V>::reference&
williamr@2:   get(const readable_property_map_archetype<K,V>&, 
williamr@2:       const typename readable_property_map_archetype<K,V>::key_type&)
williamr@2:   {
williamr@2:     typedef typename readable_property_map_archetype<K,V>::reference R;
williamr@2:     return static_object<R>::get();
williamr@2:   }
williamr@2: 
williamr@2: 
williamr@2:   template <class PMap, class Key>
williamr@2:   struct WritablePropertyMapConcept
williamr@2:   {
williamr@2:     typedef typename property_traits<PMap>::key_type key_type;
williamr@2:     typedef typename property_traits<PMap>::category Category;
williamr@2:     typedef boost::writable_property_map_tag WritableTag;
williamr@2:     void constraints() {
williamr@2:       function_requires< ConvertibleConcept<Category, WritableTag> >();
williamr@2:       put(pmap, k, val);
williamr@2:     }
williamr@2:     PMap pmap;
williamr@2:     Key k;
williamr@2:     typename property_traits<PMap>::value_type val;
williamr@2:   };
williamr@2:   template <typename KeyArchetype, typename ValueArchetype>
williamr@2:   struct writable_property_map_archetype {
williamr@2:     typedef KeyArchetype key_type;
williamr@2:     typedef ValueArchetype value_type;
williamr@2:     typedef void reference;
williamr@2:     typedef writable_property_map_tag category;
williamr@2:   };
williamr@2:   template <typename K, typename V>
williamr@2:   void put(const writable_property_map_archetype<K,V>&, 
williamr@2:            const typename writable_property_map_archetype<K,V>::key_type&, 
williamr@2:            const typename writable_property_map_archetype<K,V>::value_type&) { }
williamr@2: 
williamr@2: 
williamr@2:   template <class PMap, class Key>
williamr@2:   struct ReadWritePropertyMapConcept
williamr@2:   {
williamr@2:     typedef typename property_traits<PMap>::category Category;
williamr@2:     typedef boost::read_write_property_map_tag ReadWriteTag;
williamr@2:     void constraints() {
williamr@2:       function_requires< ReadablePropertyMapConcept<PMap, Key> >();
williamr@2:       function_requires< WritablePropertyMapConcept<PMap, Key> >();
williamr@2:       function_requires< ConvertibleConcept<Category, ReadWriteTag> >();
williamr@2:     }
williamr@2:   };
williamr@2:   template <typename KeyArchetype, typename ValueArchetype>
williamr@2:   struct read_write_property_map_archetype
williamr@2:     : public readable_property_map_archetype<KeyArchetype, ValueArchetype>,
williamr@2:       public writable_property_map_archetype<KeyArchetype, ValueArchetype>
williamr@2:   {
williamr@2:     typedef KeyArchetype key_type;
williamr@2:     typedef ValueArchetype value_type;
williamr@2:     typedef convertible_to_archetype<ValueArchetype> reference;
williamr@2:     typedef read_write_property_map_tag category;
williamr@2:   };
williamr@2: 
williamr@2: 
williamr@2:   template <class PMap, class Key>
williamr@2:   struct LvaluePropertyMapConcept
williamr@2:   {
williamr@2:     typedef typename property_traits<PMap>::category Category;
williamr@2:     typedef boost::lvalue_property_map_tag LvalueTag;
williamr@2:     typedef typename property_traits<PMap>::reference reference;
williamr@2: 
williamr@2:     void constraints() {
williamr@2:       function_requires< ReadablePropertyMapConcept<PMap, Key> >();
williamr@2:       function_requires< ConvertibleConcept<Category, LvalueTag> >();
williamr@2: 
williamr@2:       typedef typename property_traits<PMap>::value_type value_type;
williamr@2:       typedef typename require_same<
williamr@2:         const value_type&, reference>::type req;
williamr@2: 
williamr@2:       reference ref = pmap[k];
williamr@2:       ignore_unused_variable_warning(ref);
williamr@2:     }
williamr@2:     PMap pmap;
williamr@2:     Key k;
williamr@2:   };
williamr@2:   template <typename KeyArchetype, typename ValueArchetype>
williamr@2:   struct lvalue_property_map_archetype
williamr@2:     : public readable_property_map_archetype<KeyArchetype, ValueArchetype>
williamr@2:   {
williamr@2:     typedef KeyArchetype key_type;
williamr@2:     typedef ValueArchetype value_type;
williamr@2:     typedef const ValueArchetype& reference;
williamr@2:     typedef lvalue_property_map_tag category;
williamr@2:     const value_type& operator[](const key_type&) const {
williamr@2:       return static_object<value_type>::get();
williamr@2:     }
williamr@2:   };
williamr@2: 
williamr@2:   template <class PMap, class Key>
williamr@2:   struct Mutable_LvaluePropertyMapConcept
williamr@2:   {
williamr@2:     typedef typename property_traits<PMap>::category Category;
williamr@2:     typedef boost::lvalue_property_map_tag LvalueTag;
williamr@2:     typedef typename property_traits<PMap>::reference reference;
williamr@2:     void constraints() { 
williamr@2:       boost::function_requires< ReadWritePropertyMapConcept<PMap, Key> >();
williamr@2:       boost::function_requires<ConvertibleConcept<Category, LvalueTag> >();
williamr@2:       
williamr@2:       typedef typename property_traits<PMap>::value_type value_type;
williamr@2:       typedef typename require_same<
williamr@2:         value_type&,
williamr@2:         reference>::type req;
williamr@2: 
williamr@2:       reference ref = pmap[k];
williamr@2:       ignore_unused_variable_warning(ref);
williamr@2:     }
williamr@2:     PMap pmap;
williamr@2:     Key k;
williamr@2:   };
williamr@2:   template <typename KeyArchetype, typename ValueArchetype>
williamr@2:   struct mutable_lvalue_property_map_archetype
williamr@2:     : public readable_property_map_archetype<KeyArchetype, ValueArchetype>,
williamr@2:       public writable_property_map_archetype<KeyArchetype, ValueArchetype>
williamr@2:   {
williamr@2:     typedef KeyArchetype key_type;
williamr@2:     typedef ValueArchetype value_type;
williamr@2:     typedef ValueArchetype& reference;
williamr@2:     typedef lvalue_property_map_tag category;
williamr@2:     value_type& operator[](const key_type&) const { 
williamr@2:       return static_object<value_type>::get();
williamr@2:     }
williamr@2:   };
williamr@2: 
williamr@2:   struct identity_property_map;
williamr@2: 
williamr@2:   // A helper class for constructing a property map
williamr@2:   // from a class that implements operator[]
williamr@2: 
williamr@2:   template <class Reference, class LvaluePropertyMap>
williamr@2:   struct put_get_helper { };
williamr@2: 
williamr@2:   template <class PropertyMap, class Reference, class K>
williamr@2:   inline Reference
williamr@2:   get(const put_get_helper<Reference, PropertyMap>& pa, const K& k)
williamr@2:   {
williamr@2:     Reference v = static_cast<const PropertyMap&>(pa)[k];
williamr@2:     return v;
williamr@2:   }
williamr@2:   template <class PropertyMap, class Reference, class K, class V>
williamr@2:   inline void
williamr@2:   put(const put_get_helper<Reference, PropertyMap>& pa, K k, const V& v)
williamr@2:   {
williamr@2:     static_cast<const PropertyMap&>(pa)[k] = v;
williamr@2:   }
williamr@2: 
williamr@2:   //=========================================================================
williamr@2:   // Adapter to turn a RandomAccessIterator into a property map
williamr@2: 
williamr@2:   template <class RandomAccessIterator, 
williamr@2:     class IndexMap
williamr@2: #ifdef BOOST_NO_STD_ITERATOR_TRAITS
williamr@2:     , class T, class R
williamr@2: #else
williamr@2:     , class T = typename std::iterator_traits<RandomAccessIterator>::value_type
williamr@2:     , class R = typename std::iterator_traits<RandomAccessIterator>::reference
williamr@2: #endif
williamr@2:      >
williamr@2:   class iterator_property_map
williamr@2:     : public boost::put_get_helper< R, 
williamr@2:         iterator_property_map<RandomAccessIterator, IndexMap,
williamr@2:         T, R> >
williamr@2:   {
williamr@2:   public:
williamr@2:     typedef typename property_traits<IndexMap>::key_type key_type;
williamr@2:     typedef T value_type;
williamr@2:     typedef R reference;
williamr@2:     typedef boost::lvalue_property_map_tag category;
williamr@2: 
williamr@2:     inline iterator_property_map(
williamr@2:       RandomAccessIterator cc = RandomAccessIterator(), 
williamr@2:       const IndexMap& _id = IndexMap() ) 
williamr@2:       : iter(cc), index(_id) { }
williamr@2:     inline R operator[](key_type v) const { return *(iter + get(index, v)) ; }
williamr@2:   protected:
williamr@2:     RandomAccessIterator iter;
williamr@2:     IndexMap index;
williamr@2:   };
williamr@2: 
williamr@2: #if !defined BOOST_NO_STD_ITERATOR_TRAITS
williamr@2:   template <class RAIter, class ID>
williamr@2:   inline iterator_property_map<
williamr@2:     RAIter, ID,
williamr@2:     typename std::iterator_traits<RAIter>::value_type,
williamr@2:     typename std::iterator_traits<RAIter>::reference>
williamr@2:   make_iterator_property_map(RAIter iter, ID id) {
williamr@2:     function_requires< RandomAccessIteratorConcept<RAIter> >();
williamr@2:     typedef iterator_property_map<
williamr@2:       RAIter, ID,
williamr@2:       typename std::iterator_traits<RAIter>::value_type,
williamr@2:       typename std::iterator_traits<RAIter>::reference> PA;
williamr@2:     return PA(iter, id);
williamr@2:   }
williamr@2: #endif
williamr@2:   template <class RAIter, class Value, class ID>
williamr@2:   inline iterator_property_map<RAIter, ID, Value, Value&>
williamr@2:   make_iterator_property_map(RAIter iter, ID id, Value) {
williamr@2:     function_requires< RandomAccessIteratorConcept<RAIter> >();
williamr@2:     typedef iterator_property_map<RAIter, ID, Value, Value&> PMap;
williamr@2:     return PMap(iter, id);
williamr@2:   }
williamr@2: 
williamr@2:   template <class RandomAccessIterator, 
williamr@2:     class IndexMap
williamr@2: #ifdef BOOST_NO_STD_ITERATOR_TRAITS
williamr@2:     , class T, class R
williamr@2: #else
williamr@2:     , class T = typename std::iterator_traits<RandomAccessIterator>::value_type
williamr@2:     , class R = typename std::iterator_traits<RandomAccessIterator>::reference
williamr@2: #endif
williamr@2:      >
williamr@2:   class safe_iterator_property_map
williamr@2:     : public boost::put_get_helper< R, 
williamr@2:         safe_iterator_property_map<RandomAccessIterator, IndexMap,
williamr@2:         T, R> >
williamr@2:   {
williamr@2:   public:
williamr@2:     typedef typename property_traits<IndexMap>::key_type key_type; 
williamr@2:     typedef T value_type;
williamr@2:     typedef R reference;
williamr@2:     typedef boost::lvalue_property_map_tag category;
williamr@2: 
williamr@2:     inline safe_iterator_property_map(
williamr@2:       RandomAccessIterator first, 
williamr@2:       std::size_t n_ = 0, 
williamr@2:       const IndexMap& _id = IndexMap() ) 
williamr@2:       : iter(first), n(n_), index(_id) { }
williamr@2:     inline safe_iterator_property_map() { }
williamr@2:     inline R operator[](key_type v) const {
williamr@2:       assert(get(index, v) < n);
williamr@2:       return *(iter + get(index, v)) ;
williamr@2:     }
williamr@2:     typename property_traits<IndexMap>::value_type size() const { return n; }
williamr@2:   protected:
williamr@2:     RandomAccessIterator iter;
williamr@2:     typename property_traits<IndexMap>::value_type n;
williamr@2:     IndexMap index;
williamr@2:   };
williamr@2: 
williamr@2: #if !defined BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
williamr@2:   template <class RAIter, class ID>
williamr@2:   inline safe_iterator_property_map<
williamr@2:     RAIter, ID,
williamr@2:     typename boost::detail::iterator_traits<RAIter>::value_type,
williamr@2:     typename boost::detail::iterator_traits<RAIter>::reference>
williamr@2:   make_safe_iterator_property_map(RAIter iter, std::size_t n, ID id) {
williamr@2:     function_requires< RandomAccessIteratorConcept<RAIter> >();
williamr@2:     typedef safe_iterator_property_map<
williamr@2:       RAIter, ID,
williamr@2:       typename boost::detail::iterator_traits<RAIter>::value_type,
williamr@2:       typename boost::detail::iterator_traits<RAIter>::reference> PA;
williamr@2:     return PA(iter, n, id);
williamr@2:   }
williamr@2: #endif
williamr@2:   template <class RAIter, class Value, class ID>
williamr@2:   inline safe_iterator_property_map<RAIter, ID, Value, Value&>
williamr@2:   make_safe_iterator_property_map(RAIter iter, std::size_t n, ID id, Value) {
williamr@2:     function_requires< RandomAccessIteratorConcept<RAIter> >();
williamr@2:     typedef safe_iterator_property_map<RAIter, ID, Value, Value&> PMap;
williamr@2:     return PMap(iter, n, id);
williamr@2:   }
williamr@2: 
williamr@2:   //=========================================================================
williamr@2:   // An adaptor to turn a Unique Pair Associative Container like std::map or
williamr@2:   // std::hash_map into an Lvalue Property Map.
williamr@2: 
williamr@2:   template <typename UniquePairAssociativeContainer>
williamr@2:   class associative_property_map
williamr@2:     : public boost::put_get_helper<
williamr@2:        typename UniquePairAssociativeContainer::value_type::second_type&,
williamr@2:        associative_property_map<UniquePairAssociativeContainer> >
williamr@2:   {
williamr@2:     typedef UniquePairAssociativeContainer C;
williamr@2:   public:
williamr@2:     typedef typename C::key_type key_type;
williamr@2:     typedef typename C::value_type::second_type value_type;
williamr@2:     typedef value_type& reference;
williamr@2:     typedef lvalue_property_map_tag category;
williamr@2:     associative_property_map() : m_c(0) { }
williamr@2:     associative_property_map(C& c) : m_c(&c) { }
williamr@2:     reference operator[](const key_type& k) const {
williamr@2:       return (*m_c)[k];
williamr@2:     }
williamr@2:   private:
williamr@2:     C* m_c;
williamr@2:   };
williamr@2: 
williamr@2:   template <class UniquePairAssociativeContainer>
williamr@2:   associative_property_map<UniquePairAssociativeContainer>
williamr@2:   make_assoc_property_map(UniquePairAssociativeContainer& c)
williamr@2:   {
williamr@2:     return associative_property_map<UniquePairAssociativeContainer>(c);
williamr@2:   }
williamr@2: 
williamr@2:   template <typename UniquePairAssociativeContainer>
williamr@2:   class const_associative_property_map
williamr@2:     : public boost::put_get_helper<
williamr@2:        const typename UniquePairAssociativeContainer::value_type::second_type&,
williamr@2:        const_associative_property_map<UniquePairAssociativeContainer> >
williamr@2:   {
williamr@2:     typedef UniquePairAssociativeContainer C;
williamr@2:   public:
williamr@2:     typedef typename C::key_type key_type;
williamr@2:     typedef typename C::value_type::second_type value_type;
williamr@2:     typedef const value_type& reference;
williamr@2:     typedef lvalue_property_map_tag category;
williamr@2:     const_associative_property_map() : m_c(0) { }
williamr@2:     const_associative_property_map(const C& c) : m_c(&c) { }
williamr@2:     reference operator[](const key_type& k) const {
williamr@2:       return m_c->find(k)->second;
williamr@2:     }
williamr@2:   private:
williamr@2:     C const* m_c;
williamr@2:   };
williamr@2:   
williamr@2:   template <class UniquePairAssociativeContainer>
williamr@2:   const_associative_property_map<UniquePairAssociativeContainer>
williamr@2:   make_assoc_property_map(const UniquePairAssociativeContainer& c)
williamr@2:   {
williamr@2:     return const_associative_property_map<UniquePairAssociativeContainer>(c);
williamr@2:   }
williamr@2: 
williamr@2:   //=========================================================================
williamr@2:   // A property map that applies the identity function to integers
williamr@2:   struct identity_property_map
williamr@2:     : public boost::put_get_helper<std::size_t, 
williamr@2:         identity_property_map>
williamr@2:   {
williamr@2:     typedef std::size_t key_type;
williamr@2:     typedef std::size_t value_type;
williamr@2:     typedef std::size_t reference;
williamr@2:     typedef boost::readable_property_map_tag category;
williamr@2: 
williamr@2:     inline value_type operator[](const key_type& v) const { return v; }
williamr@2:   };
williamr@2: 
williamr@2:   //=========================================================================
williamr@2:   // A property map that does not do anything, for
williamr@2:   // when you have to supply a property map, but don't need it.
williamr@2:   namespace detail {
williamr@2:     struct dummy_pmap_reference {
williamr@2:       template <class T>
williamr@2:       dummy_pmap_reference& operator=(const T&) { return *this; }
williamr@2:       operator int() { return 0; }
williamr@2:     };
williamr@2:   }
williamr@2:   class dummy_property_map 
williamr@2:     : public boost::put_get_helper<detail::dummy_pmap_reference,
williamr@2:         dummy_property_map  > 
williamr@2:   {
williamr@2:   public:
williamr@2:     typedef void key_type; 
williamr@2:     typedef int value_type;
williamr@2:     typedef detail::dummy_pmap_reference reference;
williamr@2:     typedef boost::read_write_property_map_tag category;
williamr@2:     inline dummy_property_map() : c(0) { }
williamr@2:     inline dummy_property_map(value_type cc) : c(cc) { }
williamr@2:     inline dummy_property_map(const dummy_property_map& x)
williamr@2:       : c(x.c) { }
williamr@2:     template <class Vertex>
williamr@2:     inline reference operator[](Vertex) const { return reference(); }
williamr@2:    protected:
williamr@2:     value_type c;
williamr@2:   };
williamr@2: 
williamr@2: 
williamr@2: } // namespace boost
williamr@2: 
williamr@2: 
williamr@2: #endif /* BOOST_PROPERTY_MAP_HPP */
williamr@2: