iterator_range.hpp

support vector clustering for vc++

            bool operator!=( const iterator_range& r ) const
            {
                return !operator==(r);
            }

           bool operator<( const iterator_range& r ) const
           {
                return iterator_range_detail::less_than( *this, r );
           }

#endif            

        public: // convenience
           reference front() const
           {
               BOOST_ASSERT( !empty() );
               return *m_Begin;
           }
    
           reference back() const
           {
               BOOST_ASSERT( !empty() );
               IteratorT last( m_End );
               return *--last;
           }
    
           reference operator[]( size_type sz ) const
           {
               //BOOST_STATIC_ASSERT( is_random_access );
               BOOST_ASSERT( sz < size() );
               return m_Begin[sz];
           }

           iterator_range& advance_begin( difference_type n )
           {
               std::advance( m_Begin, n );
               return *this;
           }
           
           iterator_range& advance_end( difference_type n )
           {
               std::advance( m_End, n );
               return *this;
           }
           
        private:
            // begin and end iterators
            IteratorT m_Begin;
            IteratorT m_End;
            bool      singular;
        };

//  iterator range free-standing operators ---------------------------//

#ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
#else
        template< class Iterator >
        inline bool empty( const iterator_range<Iterator>& r )
        {
            //
            // this will preserve the well-defined empty() even 
            // though 'r' is singular.
            //
            return r.empty();
        }
#endif

#ifndef BOOST_OLD_IOSTREAMS   

        //! iterator_range output operator
        /*!
            Output the range to an ostream. Elements are outputed
            in a sequence without separators.
        */
        template< typename IteratorT, typename Elem, typename Traits >
        inline std::basic_ostream<Elem,Traits>& operator<<( 
                    std::basic_ostream<Elem, Traits>& Os,
                    const iterator_range<IteratorT>& r )
        {
            std::copy( r.begin(), r.end(), 
                       std::ostream_iterator< BOOST_DEDUCED_TYPENAME 
                                            iterator_value<IteratorT>::type, 
                                              Elem, Traits>(Os) );
            return Os;
        }

#else

        //! iterator_range output operator
        /*!
            Output the range to an ostream. Elements are outputed
            in a sequence without separators.
        */
        template< typename IteratorT >
        inline std::ostream& operator<<( 
                    std::ostream& Os,
                    const iterator_range<IteratorT>& r )
        {
            std::copy( r.begin(), r.end(), std::ostream_iterator<char>(Os));
            return Os;
        }

#endif

        /////////////////////////////////////////////////////////////////////
        // comparison operators
        /////////////////////////////////////////////////////////////////////

        template< class IteratorT, class ForwardRange >
        inline bool operator==( const ForwardRange& l, 
                                const iterator_range<IteratorT>& r )
        {
            return iterator_range_detail::equal( l, r );
        }

        template< class IteratorT, class ForwardRange >
        inline bool operator!=( const ForwardRange& l, 
                                const iterator_range<IteratorT>& r )
        {
            return !iterator_range_detail::equal( l, r );
        }

        template< class IteratorT, class ForwardRange >
        inline bool operator<( const ForwardRange& l, 
                               const iterator_range<IteratorT>& r )
        {
            return iterator_range_detail::less_than( l, r );
        }

#ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
#else
        template< class Iterator1T, class Iterator2T >
        inline bool operator==( const iterator_range<Iterator1T>& l, 
                                const iterator_range<Iterator2T>& r )
        {
            return iterator_range_detail::equal( l, r );
        }

        template< class IteratorT, class ForwardRange >
        inline bool operator==( const iterator_range<IteratorT>& l, 
                                const ForwardRange& r )
        {
            return iterator_range_detail::equal( l, r );
        }


        template< class Iterator1T, class Iterator2T >
        inline bool operator!=( const iterator_range<Iterator1T>& l, 
                                const iterator_range<Iterator2T>& r )
        {
            return !iterator_range_detail::equal( l, r );
        }
        
        template< class IteratorT, class ForwardRange >
        inline bool operator!=( const iterator_range<IteratorT>& l, 
                                const ForwardRange& r )
        {
            return !iterator_range_detail::equal( l, r );
        }

        
        template< class Iterator1T, class Iterator2T >
        inline bool operator<( const iterator_range<Iterator1T>& l, 
                               const iterator_range<Iterator2T>& r )
        {
            return iterator_range_detail::less_than( l, r );
        }

        template< class IteratorT, class ForwardRange >
        inline bool operator<( const iterator_range<IteratorT>& l, 
                               const ForwardRange& r )
        {            
            return iterator_range_detail::less_than( l, r );
        }

#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
                    
//  iterator range utilities -----------------------------------------//

        //! iterator_range construct helper 
        /*!
            Construct an \c iterator_range from a pair of iterators

            \param Begin A begin iterator
            \param End An end iterator
            \return iterator_range object
        */
        template< typename IteratorT >
        inline iterator_range< IteratorT > 
        make_iterator_range( IteratorT Begin, IteratorT End ) 
        {   
            return iterator_range<IteratorT>( Begin, End );
        }
                     
#ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING

        template< typename Range >
        inline iterator_range< BOOST_DEDUCED_TYPENAME range_result_iterator<Range>::type >
        make_iterator_range( Range& r ) 
        {   
            return iterator_range< BOOST_DEDUCED_TYPENAME range_result_iterator<Range>::type >
                ( boost::begin( r ), boost::end( r ) );
        }
        
#else
        //! iterator_range construct helper
        /*!
            Construct an \c iterator_range from a \c Range containing the begin
            and end iterators.
        */
        template< class ForwardRange >
        inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<ForwardRange>::type >
        make_iterator_range( ForwardRange& r ) 
        {   
           return iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<ForwardRange>::type >
                ( r, iterator_range_detail::range_tag() );
        }

        template< class ForwardRange >
        inline iterator_range< BOOST_DEDUCED_TYPENAME range_const_iterator<ForwardRange>::type >
        make_iterator_range( const ForwardRange& r ) 
        {   
           return iterator_range< BOOST_DEDUCED_TYPENAME range_const_iterator<ForwardRange>::type >
                ( r, iterator_range_detail::const_range_tag() );
        }

#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING

        namespace iterator_range_detail
        {    
            template< class Range >
            inline iterator_range< BOOST_DEDUCED_TYPENAME range_result_iterator<Range>::type >
            make_range_impl( Range& r, 
                             BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
                             BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
            {
                if( advance_begin == 0 && advance_end == 0 )
                    return make_iterator_range( r );

                BOOST_DEDUCED_TYPENAME range_result_iterator<Range>::type 
                    new_begin = boost::begin( r ),
                    new_end   = boost::end( r );
                std::advance( new_begin, advance_begin );
                std::advance( new_end, advance_end );
                return make_iterator_range( new_begin, new_end );
            }
        }
        
#ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING

        template< class Range >
        inline iterator_range< BOOST_DEDUCED_TYPENAME range_result_iterator<Range>::type >
        make_iterator_range( Range& r, 
                    BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
                    BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
        {
            //BOOST_ASSERT( advance_begin - advance_end <= size(r) && "creating invalid range" );
            return iterator_range_detail::make_range_impl( r, advance_begin, advance_end );
        }

#else

        template< class Range >
        inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<Range>::type >
        make_iterator_range( Range& r, 
                    BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
                    BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
        {
            //BOOST_ASSERT( advance_begin - advance_end <= size(r) && "creating invalid range" );
            return iterator_range_detail::make_range_impl( r, advance_begin, advance_end );
        }

        template< class Range >
        inline iterator_range< BOOST_DEDUCED_TYPENAME range_const_iterator<Range>::type >
        make_iterator_range( const Range& r, 
                    BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
                    BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
        {
            //BOOST_ASSERT( advance_begin - advance_end <= size(r) && "creating invalid range" );
            return iterator_range_detail::make_range_impl( r, advance_begin, advance_end );
        }

#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING

        //! copy a range into a sequence
        /*!
            Construct a new sequence of the specified type from the elements
            in the given range

            \param Range An input range
            \return New sequence
        */
        template< typename SeqT, typename Range >
        inline SeqT copy_range( const Range& r )
        {
            return SeqT( boost::begin( r ), boost::end( r ) );
        }

} // namespace 'boost'

#undef BOOST_OLD_IOSTREAMS

#endif