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