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Enlarge regexp capture groups

After a day of hacking and reading, I was not lucky with a regex engine, I hope someone here can help.

I want to capture the first field from each row, where the last field corresponds to some input.

string input =
    "449 a dingo ate my baby THING\n"
    "448 a dingo ate my baby THING\n"
    "445 a dingo ate my baby BOOGNISH\n"
    "446 a dingo ate my baby BOOGNISH\n"
    "447 a dingo ate my baby STUFF\n";

Let's say I give my regular expression the following line ...

string re = "^([0-9]+).+?boognish$";
boost::regex expression(re,boost::regex::perl | boost:regex::icase);

and then adjust the match

const int subs[] = { 0, 1 };
boost::sregex_token_iterator it(input.begin(), input.end(), expression, subs);
boost::sregex_token_iterator end;

while ( it != end )

{
    fprintf(stderr,"%s|\n", it->str().c_str());
    *it++;
}

Here is the result that I get from the promotion, keep in mind that I asked for the whole line and group 1, I also asked for "|" so we can easily see the end of the line:

449     a dingo ate my baby         THING
448     a dingo ate my baby        THING
445     a dingo ate my baby         BOOGNISH|
449|
446     a dingo ate my baby         BOOGNISH|
446|

I really want 445 | and 446 | only, but he gives me 449 (until he gets to the first BOGNIS), and then 446. I tested it on other reparators, and it seems to work fine. What am I doing wrong with the promotion?

Thank you in advance!

+5
1

this articale flag match_not_dot_newline . , .

+1

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