Re^3: Regex question

moritz's example is meant to be used with the x modifier which permits comments in a regex. For example:

my $re= qr{\[\[            # opening delimiter
(               # capture...
  (?:           # a group
    (?!\]\])    #    that does not start with ]]
    .           #    and is a single character long
  )+            # and many of these groups, at least one.
)
]]              # closing delimiter
}x;

while ($test =~ m{$re}g) {
  print "FOO:<$1>\n";
}
[download]

Comment on Re^3: Regex question - negatives Select or Download Code

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Re^4: Regex question - negatives by ultranerds (Hermit) on Jan 13, 2011 at 10:51 UTC
Hi, Ah cool, didn't know about that feature either =) Seems it doesn't wanna work with a s/// though? This works fine, and prints out all the tag I expected: `while ($test =~ m{$re}g) { print "FOO:<$1>\n"; }` [download] ..while this only prints out the "test new line" one for some reason? `$test =~ s{$re}{ print "BLA: $1 \n"; }ge` [download] EDIT, never mind - me being stupid with my syntax ;) TIA Andy	[reply] [d/l] [select]
Re^5: Regex question - negatives by jwkrahn (Abbot) on Jan 13, 2011 at 11:10 UTC
..while this only prints out the "test new line" one for some reason? `while ($test =~ s{$re}{}ge) {` `print "BLA: $1 \n";` `}` That is because `s///g` ignores context and just does all the replacements at once leaving the last match in `$1`. But `m//g` in scalar context will iterate through each match every time it is called in scalar context so that in a while loop `$1` will contain each match in turn.	[reply] [d/l] [select]
Re^5: Regex question - negatives by ELISHEVA (Prior) on Jan 13, 2011 at 11:00 UTC
Those "ah cool, I didn't know about that" moments are one reason I hang out around here. And you thought you were just going to get another set of eyes on your code....see Don't go all PerlMonks on me :-)	[reply]
Re^6: Regex question - negatives by ultranerds (Hermit) on Jan 13, 2011 at 11:03 UTC
heheh yeah, me too! Don't know where I would be without people like you on perlmonks - has saved my sanity many many times ;) BTW - that code works a charm :) `my $re= qr{\[\[ # opening delimiter ( # capture... (?: # a group (?!\]\]) # that does not start with ]] . # and is a single character long )+ # and many of these groups, at least one. ) \]\] # closing delimiter }x; $section_contents =~ s{$re}{Process_Tag($1,$hidden_query,$tag_cfg, +$is_preview)}ge; # process stuff like [[1234]] or [[http://www.site.c +om]]` [download] Thanks again everyone! Cheers Andy	[reply] [d/l]