Chris@16: //  Boost string_algo library join.hpp header file  ---------------------------//
Chris@16: 
Chris@16: //  Copyright Pavol Droba 2002-2006.
Chris@16: //
Chris@16: // Distributed under the Boost Software License, Version 1.0.
Chris@16: //    (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: //          http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: //  See http://www.boost.org/ for updates, documentation, and revision history.
Chris@16: 
Chris@16: #ifndef BOOST_STRING_JOIN_HPP
Chris@16: #define BOOST_STRING_JOIN_HPP
Chris@16: 
Chris@16: #include <boost/algorithm/string/config.hpp>
Chris@16: #include <boost/algorithm/string/detail/sequence.hpp>
Chris@16: #include <boost/range/value_type.hpp>
Chris@16: #include <boost/range/as_literal.hpp>
Chris@16: 
Chris@16: /*! \file
Chris@16:     Defines join algorithm. 
Chris@16: 
Chris@16:     Join algorithm is a counterpart to split algorithms.
Chris@16:     It joins strings from a 'list' by adding user defined separator.
Chris@16:     Additionally there is a version that allows simple filtering
Chris@16:     by providing a predicate.
Chris@16: */
Chris@16: 
Chris@16: namespace boost {
Chris@16:     namespace algorithm {
Chris@16: 
Chris@16: //  join --------------------------------------------------------------//
Chris@16: 
Chris@16:         //! Join algorithm
Chris@16:         /*!
Chris@16:             This algorithm joins all strings in a 'list' into one long string.
Chris@16:             Segments are concatenated by given separator.
Chris@16: 
Chris@16:             \param Input A container that holds the input strings. It must be a container-of-containers.
Chris@16:             \param Separator A string that will separate the joined segments.
Chris@16:             \return Concatenated string.
Chris@16: 
Chris@16:             \note This function provides the strong exception-safety guarantee
Chris@16:         */
Chris@16:         template< typename SequenceSequenceT, typename Range1T>
Chris@16:         inline typename range_value<SequenceSequenceT>::type 
Chris@16:         join(
Chris@16:             const SequenceSequenceT& Input,
Chris@16:             const Range1T& Separator)
Chris@16:         {
Chris@16:             // Define working types
Chris@16:             typedef typename range_value<SequenceSequenceT>::type ResultT;
Chris@16:             typedef typename range_const_iterator<SequenceSequenceT>::type InputIteratorT;
Chris@16: 
Chris@16:             // Parse input
Chris@16:             InputIteratorT itBegin=::boost::begin(Input);
Chris@16:             InputIteratorT itEnd=::boost::end(Input);
Chris@16: 
Chris@16:             // Construct container to hold the result
Chris@16:             ResultT Result;
Chris@16:             
Chris@16:             // Append first element
Chris@16:             if(itBegin!=itEnd)
Chris@16:             {
Chris@16:                 detail::insert(Result, ::boost::end(Result), *itBegin);
Chris@16:                 ++itBegin;
Chris@16:             }
Chris@16: 
Chris@16:             for(;itBegin!=itEnd; ++itBegin)
Chris@16:             {
Chris@16:                 // Add separator
Chris@16:                 detail::insert(Result, ::boost::end(Result), ::boost::as_literal(Separator));
Chris@16:                 // Add element
Chris@16:                 detail::insert(Result, ::boost::end(Result), *itBegin);
Chris@16:             }
Chris@16: 
Chris@16:             return Result;
Chris@16:         }
Chris@16: 
Chris@16: // join_if ----------------------------------------------------------//
Chris@16: 
Chris@16:         //! Conditional join algorithm
Chris@16:         /*!
Chris@16:             This algorithm joins all strings in a 'list' into one long string.
Chris@16:             Segments are concatenated by given separator. Only segments that
Chris@16:             satisfy the predicate will be added to the result.
Chris@16: 
Chris@16:             \param Input A container that holds the input strings. It must be a container-of-containers.
Chris@16:             \param Separator A string that will separate the joined segments.
Chris@16:             \param Pred A segment selection predicate
Chris@16:             \return Concatenated string.
Chris@16: 
Chris@16:             \note This function provides the strong exception-safety guarantee
Chris@16:         */
Chris@16:         template< typename SequenceSequenceT, typename Range1T, typename PredicateT>
Chris@16:         inline typename range_value<SequenceSequenceT>::type 
Chris@16:         join_if(
Chris@16:             const SequenceSequenceT& Input,
Chris@16:             const Range1T& Separator,
Chris@16:             PredicateT Pred)
Chris@16:         {
Chris@16:             // Define working types
Chris@16:             typedef typename range_value<SequenceSequenceT>::type ResultT;
Chris@16:             typedef typename range_const_iterator<SequenceSequenceT>::type InputIteratorT;
Chris@16: 
Chris@16:             // Parse input
Chris@16:             InputIteratorT itBegin=::boost::begin(Input);
Chris@16:             InputIteratorT itEnd=::boost::end(Input);
Chris@16: 
Chris@16:             // Construct container to hold the result
Chris@16:             ResultT Result;
Chris@16: 
Chris@16:             // Roll to the first element that will be added
Chris@16:             while(itBegin!=itEnd && !Pred(*itBegin)) ++itBegin;
Chris@16:             // Add this element
Chris@16:             if(itBegin!=itEnd)
Chris@16:             {
Chris@16:                 detail::insert(Result, ::boost::end(Result), *itBegin);
Chris@16:                 ++itBegin;
Chris@16:             }
Chris@16: 
Chris@16:             for(;itBegin!=itEnd; ++itBegin)
Chris@16:             {
Chris@16:                 if(Pred(*itBegin))
Chris@16:                 {
Chris@16:                     // Add separator
Chris@16:                     detail::insert(Result, ::boost::end(Result), ::boost::as_literal(Separator));
Chris@16:                     // Add element
Chris@16:                     detail::insert(Result, ::boost::end(Result), *itBegin);
Chris@16:                 }
Chris@16:             }
Chris@16: 
Chris@16:             return Result;
Chris@16:         }
Chris@16: 
Chris@16:     } // namespace algorithm
Chris@16: 
Chris@16:     // pull names to the boost namespace
Chris@16:     using algorithm::join;
Chris@16:     using algorithm::join_if;
Chris@16: 
Chris@16: } // namespace boost
Chris@16: 
Chris@16: 
Chris@16: #endif  // BOOST_STRING_JOIN_HPP
Chris@16: