Anonymous Monk:

It's certainly possible to use both \G and ^ in a regular expression, but I expect that would be a very unusual use case. Both are markers telling the regex a reference point in a string. I've never needed to use both in a regex before, but you can certainly do it. Here's a contrived example:

$ cat gah.pl
use strict;
use warnings;

my $t = "The quick red fox jumped over the lazy brown dog.";

if ($t =~ /(jump)/g) {
    print "Found $1 ending at ", pos($t), ".\n";
}

if ($t =~ /(\w+)\s+(\w+)\G/) {
    print "Found <$1> before <$2>\n";
}

$t = <<EOTxt;
Now a funkier thing we can
do is to find weird stuffs
such as the text before a word
on the same line
EOTxt

if ($t =~ /(weird)/g) {
    print "Found $1\n";
    if ($t =~ /^([^\n]+)\G/gm) {
        print "<$1>\n";
    }
}

$ perl gah.pl
Found jump ending at 22.
Found <fox> before <jump>
Found weird
<do is to find weird>

[download]

...roboticus

When your only tool is a hammer, all problems look like your thumb.

In reply to Re: anchor ^ and \G by roboticus
in thread anchor ^ and \G by Anonymous Monk

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