Re: [Boost-users] .Net equalent Options in regex

From: John Maddock (john_at_[hidden])
Date: 2005-08-12 07:33:10

All of the following comments apply to the newly release Boost-1.33

> *Multiline*

multiline is on by default.  To turn it off either:

1) prefix your expression with (?-m)
2) compile your expression with the flag no_mod_m set:    boost::regex 
r("^abc", boost::regex::perl | boost::regex::no_mod_m);
3) Pass the "match_single_line" flag to one of the matching/searching 
algorithms/iterators.

>  *ExplicitCapture*

Named captures aren't supported.

>     *Singleline*

This is on by default, you can turn it off by either:

1) Prefix your expression with (?-s)
2) Compile the expression with the flag no_mod_s set:    boost::regex 
r("^abc", boost::regex::perl | boost::regex::no_mod_s);
3) Pass " match_not_dot_newline" flag to one of the matching/searching 
algorithms/iterators.

>  *IgnorePatternWhitespace*

Is this the same as Perl's x-modifier?  If so then either:

1) Prefix your expression with (?x)
2) Compile your expression with the flag mod_x set:    boost::regex 
r("^abc", boost::regex::perl | boost::regex::mod_x);

John.