Chris@16: //  Copyright Neil Groves 2010. Use, modification and
Chris@16: //  distribution is subject to the Boost Software License, Version
Chris@16: //  1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: //  http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //
Chris@16: //
Chris@16: // For more information, see http://www.boost.org/libs/range/
Chris@16: //
Chris@16: #ifndef BOOST_RANGE_COMBINE_HPP
Chris@16: #define BOOST_RANGE_COMBINE_HPP
Chris@16: 
Chris@16: #include <boost/iterator/zip_iterator.hpp>
Chris@16: #include <boost/tuple/tuple.hpp>
Chris@16: #include <boost/range/iterator.hpp>
Chris@16: #include <boost/range/iterator_range.hpp>
Chris@16: #include <boost/type_traits/is_void.hpp>
Chris@16: #include <boost/type_traits/is_same.hpp>
Chris@16: #include <boost/mpl/eval_if.hpp>
Chris@16: #include <boost/mpl/int.hpp>
Chris@16: #include <boost/mpl/plus.hpp>
Chris@16: #include <boost/mpl/arithmetic.hpp>
Chris@16: #include <boost/config.hpp>
Chris@16: 
Chris@16: namespace boost
Chris@16: {
Chris@16:     namespace range_detail
Chris@16:     {
Chris@16:         struct void_ { typedef void_ type; };
Chris@16:     }
Chris@16: 
Chris@16:     template<> struct range_iterator< ::boost::range_detail::void_ >
Chris@16:     {
Chris@16:        typedef ::boost::tuples::null_type type;
Chris@16:     };
Chris@16: 
Chris@16:     namespace range_detail
Chris@16:     {
Chris@16:         inline ::boost::tuples::null_type range_begin( ::boost::range_detail::void_& )
Chris@16:         { return ::boost::tuples::null_type(); }
Chris@16: 
Chris@16:         inline ::boost::tuples::null_type range_begin( const ::boost::range_detail::void_& )
Chris@16:         { return ::boost::tuples::null_type(); }
Chris@16: 
Chris@16:         inline ::boost::tuples::null_type range_end( ::boost::range_detail::void_& )
Chris@16:         { return ::boost::tuples::null_type(); }
Chris@16: 
Chris@16:         inline ::boost::tuples::null_type range_end( const ::boost::range_detail::void_& )
Chris@16:         { return ::boost::tuples::null_type(); }
Chris@16: 
Chris@16:         template< class T >
Chris@16:         struct tuple_iter
Chris@16:         {
Chris@16:             typedef BOOST_DEDUCED_TYPENAME ::boost::mpl::eval_if_c<
Chris@16:                 ::boost::is_same<T, ::boost::range_detail::void_ >::value,
Chris@16:                 ::boost::mpl::identity< ::boost::tuples::null_type >,
Chris@16:                 ::boost::range_iterator<T>
Chris@16:             >::type type;
Chris@16:         };
Chris@16: 
Chris@16:         template< class Rng1, class Rng2 >
Chris@16:         struct tuple_range
Chris@16:         {
Chris@16:             typedef BOOST_DEDUCED_TYPENAME ::boost::mpl::eval_if_c<
Chris@16:                 ::boost::is_same<Rng1, ::boost::range_detail::void_ >::value,
Chris@16:                 ::boost::range_detail::void_,
Chris@16:                 ::boost::mpl::identity<Rng1>
Chris@16:             >::type type;
Chris@16:         };
Chris@16: 
Chris@16:         template
Chris@16:         <
Chris@16:             class R1,
Chris@16:             class R2,
Chris@16:             class R3,
Chris@16:             class R4,
Chris@16:             class R5,
Chris@16:             class R6
Chris@16:         >
Chris@16:         struct generate_tuple
Chris@16:         {
Chris@16:             typedef ::boost::tuples::tuple<
Chris@16:                         BOOST_DEDUCED_TYPENAME tuple_iter<R1>::type,
Chris@16:                         BOOST_DEDUCED_TYPENAME tuple_iter<R2>::type,
Chris@16:                         BOOST_DEDUCED_TYPENAME tuple_iter<R3>::type,
Chris@16:                         BOOST_DEDUCED_TYPENAME tuple_iter<R4>::type,
Chris@16:                         BOOST_DEDUCED_TYPENAME tuple_iter<R5>::type,
Chris@16:                         BOOST_DEDUCED_TYPENAME tuple_iter<R6>::type
Chris@16:                     > type;
Chris@16: 
Chris@16:             static type begin( R1& r1, R2& r2, R3& r3, R4& r4, R5& r5, R6& r6 )
Chris@16:             {
Chris@16:                 return ::boost::tuples::make_tuple( ::boost::begin(r1),
Chris@16:                                                     ::boost::begin(r2),
Chris@16:                                                     ::boost::begin(r3),
Chris@16:                                                     ::boost::begin(r4),
Chris@16:                                                     ::boost::begin(r5),
Chris@16:                                                     ::boost::begin(r6) );
Chris@16:             }
Chris@16: 
Chris@16:             static type end( R1& r1, R2& r2, R3& r3, R4& r4, R5& r5, R6& r6 )
Chris@16:             {
Chris@16:                 return ::boost::tuples::make_tuple( ::boost::end(r1),
Chris@16:                                                     ::boost::end(r2),
Chris@16:                                                     ::boost::end(r3),
Chris@16:                                                     ::boost::end(r4),
Chris@16:                                                     ::boost::end(r5),
Chris@16:                                                     ::boost::end(r6) );
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16:         template
Chris@16:         <
Chris@16:             class R1,
Chris@16:             class R2 = void_,
Chris@16:             class R3 = void_,
Chris@16:             class R4 = void_,
Chris@16:             class R5 = void_,
Chris@16:             class R6 = void_
Chris@16:         >
Chris@16:         struct zip_rng
Chris@16:             : iterator_range<
Chris@16:                 zip_iterator<
Chris@16:                     BOOST_DEDUCED_TYPENAME generate_tuple<R1,R2,R3,R4,R5,R6>::type
Chris@16:                 >
Chris@16:             >
Chris@16:         {
Chris@16:         private:
Chris@16:             typedef generate_tuple<R1,R2,R3,R4,R5,R6>        generator_t;
Chris@16:             typedef BOOST_DEDUCED_TYPENAME generator_t::type tuple_t;
Chris@16:             typedef zip_iterator<tuple_t>                    zip_iter_t;
Chris@16:             typedef iterator_range<zip_iter_t>               base_t;
Chris@16: 
Chris@16:         public:
Chris@16:             zip_rng( R1& r1, R2& r2, R3& r3, R4& r4, R5& r5, R6& r6 )
Chris@16:             : base_t( zip_iter_t( generator_t::begin(r1,r2,r3,r4,r5,r6) ),
Chris@16:                       zip_iter_t( generator_t::end(r1,r2,r3,r4,r5,r6) ) )
Chris@16:             {
Chris@16:                 BOOST_ASSERT(::boost::distance(r1) <= ::boost::distance(r2));
Chris@16:                 BOOST_ASSERT(::boost::distance(r1) <= ::boost::distance(r3));
Chris@16:                 BOOST_ASSERT(::boost::distance(r1) <= ::boost::distance(r4));
Chris@16:                 BOOST_ASSERT(::boost::distance(r1) <= ::boost::distance(r5));
Chris@16:                 BOOST_ASSERT(::boost::distance(r1) <= ::boost::distance(r6));
Chris@16:             }
Chris@16: 
Chris@16:             template< class Zip, class Rng >
Chris@16:             zip_rng( Zip& z, Rng& r )
Chris@16:             : base_t( zip_iter_t( generator_t::begin( z, r ) ),
Chris@16:                       zip_iter_t( generator_t::end( z, r ) ) )
Chris@16:             {
Chris@16: 
Chris@16:                 // @todo: tuple::begin( should be overloaded for this situation
Chris@16:             }
Chris@16: 
Chris@16:             struct tuple_length : ::boost::tuples::length<tuple_t>
Chris@16:             { };
Chris@16: 
Chris@16:             template< unsigned N >
Chris@16:             struct get
Chris@16:             {
Chris@16:                 template< class Z, class R >
Chris@16:                 static BOOST_DEDUCED_TYPENAME ::boost::tuples::element<N,tuple_t>::type begin( Z& z, R& )
Chris@16:                 {
Chris@16:                     return get<N>( z.begin().get_iterator_tuple() );
Chris@16:                 }
Chris@16: 
Chris@16:                 template< class Z, class R >
Chris@16:                 static BOOST_DEDUCED_TYPENAME ::boost::tuples::element<N,tuple_t>::type end( Z& z, R& r )
Chris@16:                 {
Chris@16:                     return get<N>( z.end().get_iterator_tuple() );
Chris@16:                 }
Chris@16:             };
Chris@16: 
Chris@16:         };
Chris@16: 
Chris@16:         template< class Rng1, class Rng2 >
Chris@16:         struct zip_range
Chris@16:             : iterator_range<
Chris@16:                 zip_iterator<
Chris@16:                     ::boost::tuples::tuple<
Chris@16:                         BOOST_DEDUCED_TYPENAME ::boost::range_iterator<Rng1>::type,
Chris@16:                         BOOST_DEDUCED_TYPENAME ::boost::range_iterator<Rng2>::type
Chris@16:                     >
Chris@16:                 >
Chris@16:             >
Chris@16:         {
Chris@16:         private:
Chris@16:             typedef zip_iterator<
Chris@16:                         ::boost::tuples::tuple<
Chris@16:                             BOOST_DEDUCED_TYPENAME ::boost::range_iterator<Rng1>::type,
Chris@16:                             BOOST_DEDUCED_TYPENAME ::boost::range_iterator<Rng2>::type
Chris@16:                         >
Chris@16:                     > zip_iter_t;
Chris@16:             typedef iterator_range<zip_iter_t> base_t;
Chris@16: 
Chris@16:         public:
Chris@16:             zip_range( Rng1& r1, Rng2& r2 )
Chris@16:             : base_t( zip_iter_t( ::boost::tuples::make_tuple(::boost::begin(r1),
Chris@16:                                                               ::boost::begin(r2)) ),
Chris@16:                       zip_iter_t( ::boost::tuples::make_tuple(::boost::end(r1),
Chris@16:                                                               ::boost::end(r2)) ) )
Chris@16:             {
Chris@16:                 BOOST_ASSERT(::boost::distance(r1) <= ::boost::distance(r2));
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16:         template< class Rng1, class Rng2, class Rng3 >
Chris@16:         struct zip_range3
Chris@16:             : iterator_range<
Chris@16:                 zip_iterator<
Chris@16:                     ::boost::tuples::tuple<
Chris@16:                         BOOST_DEDUCED_TYPENAME ::boost::range_iterator<Rng1>::type,
Chris@16:                         BOOST_DEDUCED_TYPENAME ::boost::range_iterator<Rng2>::type,
Chris@16:                         BOOST_DEDUCED_TYPENAME ::boost::range_iterator<Rng3>::type
Chris@16:                     >
Chris@16:                 >
Chris@16:             >
Chris@16:         {
Chris@16:         private:
Chris@16:             typedef zip_iterator<
Chris@16:                 ::boost::tuples::tuple<
Chris@16:                     BOOST_DEDUCED_TYPENAME ::boost::range_iterator<Rng1>::type,
Chris@16:                     BOOST_DEDUCED_TYPENAME ::boost::range_iterator<Rng2>::type,
Chris@16:                     BOOST_DEDUCED_TYPENAME ::boost::range_iterator<Rng3>::type
Chris@16:                 >
Chris@16:             > zip_iter_t;
Chris@16:             typedef iterator_range<zip_iter_t> base_t;
Chris@16: 
Chris@16:         public:
Chris@16:             zip_range3( Rng1& r1, Rng2& r2, Rng3& r3 )
Chris@16:             : base_t( zip_iter_t( ::boost::tuples::make_tuple(::boost::begin(r1),
Chris@16:                                                               ::boost::begin(r2),
Chris@16:                                                               ::boost::begin(r3)) ),
Chris@16:                       zip_iter_t( ::boost::tuples::make_tuple(::boost::end(r1),
Chris@16:                                                               ::boost::end(r2),
Chris@16:                                                               ::boost::end(r3)) )
Chris@16:                     )
Chris@16:             {
Chris@16:                 BOOST_ASSERT(::boost::distance(r1) <= ::boost::distance(r2));
Chris@16:                 BOOST_ASSERT(::boost::distance(r1) <= ::boost::distance(r3));
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16: 
Chris@16:         struct combine_tag {};
Chris@16: 
Chris@16:         template< class Rng >
Chris@16:         inline zip_rng<Rng>
Chris@16:         operator&( combine_tag, Rng& r )
Chris@16:         {
Chris@16:             return zip_rng<Rng>(r);
Chris@16:         }
Chris@16: 
Chris@16:         template< class Rng >
Chris@16:         inline iterator_range<const Rng>
Chris@16:         operator&( combine_tag, const Rng& r )
Chris@16:         {
Chris@16:             return iterator_range<const Rng>(r);
Chris@16:         }
Chris@16: 
Chris@16:         template
Chris@16:         <
Chris@16:             class R1,
Chris@16:             class R2,
Chris@16:             class R3,
Chris@16:             class R4,
Chris@16:             class R5,
Chris@16:             class Rng
Chris@16:         >
Chris@16:         inline BOOST_DEDUCED_TYPENAME zip_rng<R1,R2,R3,R4,R5>::next
Chris@16:         operator&( const zip_rng<R1,R2,R3,R4,R5>& zip,
Chris@16:                    Rng& r )
Chris@16:         {
Chris@16:             return zip_rng<R1,R2,R3,R4,R5>::next( zip, r );
Chris@16:         }
Chris@16: 
Chris@16:     } // namespace range_detail
Chris@16: 
Chris@16:     template< class Rng1, class Rng2 >
Chris@16:     inline ::boost::range_detail::zip_range<Rng1, Rng2> combine( Rng1& r1, Rng2& r2 )
Chris@16:     {
Chris@16:         return ::boost::range_detail::zip_range<Rng1, Rng2>(r1, r2);
Chris@16:     }
Chris@16: 
Chris@16:     template< class Rng1, class Rng2 >
Chris@16:     inline ::boost::range_detail::zip_range<const Rng1, Rng2> combine( const Rng1& r1, Rng2& r2 )
Chris@16:     {
Chris@16:         return ::boost::range_detail::zip_range<const Rng1, Rng2>(r1, r2);
Chris@16:     }
Chris@16: 
Chris@16:     template< class Rng1, class Rng2 >
Chris@16:     inline ::boost::range_detail::zip_range<Rng1, const Rng2> combine( Rng1& r1, const Rng2& r2 )
Chris@16:     {
Chris@16:         return ::boost::range_detail::zip_range<Rng1, const Rng2>(r1, r2);
Chris@16:     }
Chris@16: 
Chris@16:     template< class Rng1, class Rng2 >
Chris@16:     inline ::boost::range_detail::zip_range<const Rng1, const Rng2> combine( const Rng1& r1, const Rng2& r2 )
Chris@16:     {
Chris@16:         return ::boost::range_detail::zip_range<const Rng1, const Rng2>(r1, r2);
Chris@16:     }
Chris@16: 
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #endif