Function join_if

include/win/boost/algorithm/string/regex.hpp:506–549

            typename CharT, 
            typename RegexTraitsT >
        inline typename range_value<SequenceSequenceT>::type 
        join_if(
            const SequenceSequenceT& Input,
            const Range1T& Separator,
            const basic_regex<CharT, RegexTraitsT>& Rx,
            match_flag_type Flags=match_default )
        {
            // Define working types
            typedef typename range_value<SequenceSequenceT>::type ResultT;
            typedef typename range_const_iterator<SequenceSequenceT>::type InputIteratorT;

            // Parse input
            InputIteratorT itBegin=::boost::begin(Input);
            InputIteratorT itEnd=::boost::end(Input);

            // Construct container to hold the result
            ResultT Result;


            // Roll to the first element that will be added
            while(
                itBegin!=itEnd && 
                !::boost::regex_match(::boost::begin(*itBegin), ::boost::end(*itBegin), Rx, Flags)) ++itBegin;

            // Add this element
            if(itBegin!=itEnd)
            {
                detail::insert(Result, ::boost::end(Result), *itBegin);
                ++itBegin;
            }

            for(;itBegin!=itEnd; ++itBegin)
            {
                if(::boost::regex_match(::boost::begin(*itBegin), ::boost::end(*itBegin), Rx, Flags))
                {
                    // Add separator
                    detail::insert(Result, ::boost::end(Result), ::boost::as_literal(Separator));
                    // Add element
                    detail::insert(Result, ::boost::end(Result), *itBegin);
                }
            }

            return Result;
        }

#else  // BOOST_NO_FUNCTION_TEMPLATE_ORDERING