Boost C++ Libraries

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Function template join_if

boost::algorithm::join_if — Conditional join algorithm.

Synopsis

// In header: <boost/algorithm/string/join.hpp>


template<typename SequenceSequenceT, typename Range1T, typename PredicateT> 
  range_value< SequenceSequenceT >::type 
  join_if(const SequenceSequenceT & Input, const Range1T & Separator, 
          PredicateT Pred);

Description

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.

	Note
	This function provides the strong exception-safety guarantee

Parameters:

`Input`	A container that holds the input strings. It must be a container-of-containers.
`Pred`	A segment selection predicate
`Separator`	A string that will separate the joined segments.

Returns:

Concatenated string.