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regex_format (Deprecated)

The algorithm regex_format is deprecated; new code should use match_results<>::format instead. Existing code will continue to compile, the following documentation is taken from the previous version of Boost.Regex and will not be further updated:

Algorithm regex_format
#include <boost/regex.hpp>

The algorithm regex_format takes the results of a match and creates a new string based upon a format string, regex_format can be used for search and replace operations:

template <class OutputIterator, class iterator, class Allocator, class charT>
OutputIterator regex_format(OutputIterator out,
                           const match_results<iterator, Allocator>& m,
                           const charT* fmt,
                           match_flag_type flags = 0);
template <class OutputIterator, class iterator, class Allocator, class charT>
OutputIterator regex_format(OutputIterator out,
                           const match_results<iterator, Allocator>& m,
                           const std::basic_string<charT>& fmt,
                           match_flag_type flags = 0);

The library also defines the following convenience variation of regex_format, which returns the result directly as a string, rather than outputting to an iterator.

[Note] Note

This version may not be available, or may be available in a more limited form, depending upon your compilers capabilities

template <class iterator, class Allocator, class charT>
std::basic_string<charT> regex_format
                                 (const match_results<iterator, Allocator>& m, 
                                 const charT* fmt,
                                 match_flag_type flags = 0);

template <class iterator, class Allocator, class charT>
std::basic_string<charT> regex_format
                                 (const match_results<iterator, Allocator>& m, 
                                 const std::basic_string<charT>& fmt,
                                 match_flag_type flags = 0);

Parameters to the main version of the function are passed as follows:

Parameter

Description

OutputIterator out

An output iterator type, the output string is sent to this iterator. Typically this would be a std::ostream_iterator.

const match_results<iterator, Allocator>& m

An instance of match_results obtained from one of the matching algorithms above, and denoting what matched.

const charT* fmt

A format string that determines how the match is transformed into the new string.

unsigned flags

Optional flags which describe how the format string is to be interpreted.

Format flags are described under match_flag_type.

The format string syntax (and available options) is described more fully under format strings.


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