collection_traits_detail.hpp

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                    traits_type::value_type value_type;
                typedef BOOST_STRING_TYPENAME
                    traits_type::iterator iterator;
                typedef BOOST_STRING_TYPENAME
                    traits_type::const_iterator const_iterator;
                typedef BOOST_STRING_TYPENAME
                    traits_type::size_type size_type;
                typedef BOOST_STRING_TYPENAME
                    traits_type::difference_type difference_type;

                BOOST_STATIC_CONSTANT( size_type, array_size = traits_type::array_size );
            };

#endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
            
            // array lenght resolving
            /*
                Lenght of string contained in a static array could
                be different from the size of the array.
                For string processing we need the lenght without
                terminating 0.

                Therefore, the lenght is calulated for char and wchar_t
                using char_traits, rather then simply returning
                the array size.
            */
            template< typename T >
            struct array_length_selector
            {
                template< typename TraitsT >
                struct array_length
                {
                    typedef BOOST_STRING_TYPENAME 
                        TraitsT::size_type size_type;

                    BOOST_STATIC_CONSTANT(
                        size_type,
                        array_size=TraitsT::array_size );

                    template< typename A >
                    static size_type length( const A& )
                    {
                        return array_size;
                    }

                    template< typename A >
                    static bool empty( const A& )
                    {
                        return array_size==0;
                    }
                };
            };

            // specialization for char
            template<>
            struct array_length_selector<char>
            {
                template< typename TraitsT >
                struct array_length
                {
                    typedef BOOST_STRING_TYPENAME 
                        TraitsT::size_type size_type;

                    template< typename A >
                    static size_type length( const A& a )
                    {
                        if ( a==0 ) 
                            return 0;
                        else
                            return std::char_traits<char>::length(a);
                    }
                    
                    template< typename A >
                    static bool empty( const A& a )
                    {
                        return a==0 || a[0]==0;
                    }
                };
            };

            // specialization for wchar_t
            template<>
            struct array_length_selector<wchar_t>
            {
                template< typename TraitsT >
                struct array_length
                {
                    typedef BOOST_STRING_TYPENAME 
                        TraitsT::size_type size_type;

                    template< typename A >
                    static size_type length( const A& a )
                    {
                        if ( a==0 ) 
                            return 0;
                        else
                            return std::char_traits<wchar_t>::length(a);
                    }

                    template< typename A >
                    static bool empty( const A& a )
                    {
                        return a==0 || a[0]==0;
                    }
                };
            };

            template< typename T >
            struct array_container_traits
            {
            private:
                // resolve array traits
                typedef array_traits<T> traits_type;

            public:
                typedef BOOST_STRING_TYPENAME
                    traits_type::value_type value_type;
                typedef BOOST_STRING_TYPENAME
                    traits_type::iterator iterator;
                typedef BOOST_STRING_TYPENAME
                    traits_type::const_iterator const_iterator;
                typedef BOOST_STRING_TYPENAME
                    traits_type::size_type size_type;
                typedef BOOST_STRING_TYPENAME
                    traits_type::difference_type difference_type;

                typedef BOOST_STRING_TYPENAME
                    ::boost::mpl::if_< ::boost::is_const<T>,
                        const_iterator,
                        iterator 
                    >::type result_iterator;
                
            private:
                // resolve array size
                typedef BOOST_STRING_TYPENAME
                    ::boost::remove_cv<value_type>::type char_type;
                typedef BOOST_STRING_TYPENAME
                    array_length_selector<char_type>::
                        BOOST_NESTED_TEMPLATE array_length<traits_type> array_length_type;

            public:
                BOOST_STATIC_CONSTANT( size_type, array_size = traits_type::array_size );

                // static operations
                template< typename A >
                static size_type size( const A& a )
                {
                    return array_length_type::length(a);
                }

                template< typename A >
                static bool empty( const A& a )
                {
                    return array_length_type::empty(a);
                }
                

#ifndef BOOST_NO_FUNCTION_TEMPLATE_ORDERING

                template< typename A >
                static iterator begin( A& a )
                {
                    return a;
                }

                template< typename A >
                static const_iterator begin( const A& a )
                {
                    return a;
                }

                template< typename A >
                static iterator end( A& a )
                {
                    return a+array_length_type::length(a);
                }

                template< typename A >
                static const_iterator end( const A& a )
                {
                    return a+array_length_type::length(a);
                }

#else // BOOST_NO_FUNCTION_TEMPLATE_ORDERING

                template< typename A >
                static result_iterator begin( A& a )
                {
                    return a;
                }

                template< typename A >
                static result_iterator end( A& a )
                {
                    return a+array_length_type::length(a);
                }

#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING    

            }; 

            template<typename T>
            struct array_container_traits_selector
            {
                typedef array_container_traits<T> type;
            };

// Pointer container traits ---------------------------------------------------------------

            template<typename T>
            struct pointer_container_traits
            {
                typedef BOOST_STRING_TYPENAME
                    ::boost::remove_pointer<T>::type value_type;

                typedef BOOST_STRING_TYPENAME
                    ::boost::remove_cv<value_type>::type char_type;
                typedef ::std::char_traits<char_type> char_traits;

                typedef value_type* iterator;
                typedef const value_type* const_iterator;
                typedef std::ptrdiff_t difference_type;
                typedef std::size_t size_type;

                typedef BOOST_STRING_TYPENAME
                    ::boost::mpl::if_< ::boost::is_const<T>,
                        const_iterator,
                        iterator 
                    >::type result_iterator;

                // static operations
                template< typename P >
                static size_type size( const P& p )
                {
                    if ( p==0 ) 
                        return 0;
                    else
                        return char_traits::length(p);
                }

                template< typename P >
                static bool empty( const P& p )
                {
                    return p==0 || p[0]==0;
                }

#ifndef BOOST_NO_FUNCTION_TEMPLATE_ORDERING

                template< typename P >
                static iterator begin( P& p )
                {
                    return p;
                }

                template< typename P >
                static const_iterator begin( const P& p )
                {
                    return p;
                }

                template< typename P >
                static iterator end( P& p )
                {
                    if ( p==0 )
                        return p;
                    else
                        return p+char_traits::length(p);
                }

                template< typename P >
                static const_iterator end( const P& p )
                {
                    if ( p==0 )
                        return p;
                    else
                        return p+char_traits::length(p);
                }

#else // BOOST_NO_FUNCTION_TEMPLATE_ORDERING

                template< typename P >
                static result_iterator begin( P& p )
                {
                    return p;
                }

                template< typename P >
                static result_iterator end( P& p )
                {
                    if ( p==0 )
                        return p;
                    else
                        return p+char_traits::length(p);
                }

#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING    
            }; 

            template<typename T>
            struct pointer_container_traits_selector
            {
                typedef pointer_container_traits<T> type;
            };

        } // namespace detail
    } // namespace algorithm
} // namespace boost


#endif  // BOOST_STRING_DETAIL_COLLECTION_HPP