Re: $1 doesn't reset?

perlre tells us to use the \G anchor :

  while ($res->content =~ m/\G.*?foo(.*?)bar/g) {
    print "$_ - $1\n";
  };
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Maybe you'll want to read Death to Dot Star! before you use .*?, but unless we know more about the data, .*? will have to do ;-)

Update: If I run this program :

#!/usr/bin/perl -w
use strict;

my $string = "fooAbar" .
             "fooBbar" .
             "gooCbar" .
             "fooDfooEbar" .
             "foo";

while ($string =~ m/\G.*?foo(.*?)bar/g) {
  print $1, "\n";
};
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I get the following, expected output :

H:\>perl -w test.pl
A
B
DfooE
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I guess the error lies somewhere else in your regular expression then - maybe post the whole RE together with some sample data.

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Re: Re: $1 doesn't reset? by alfie (Pilgrim) on Mar 20, 2001 at 15:54 UTC
Yes, thanks for the \G info - but somehow it still works if I use $_ within the for loop. Also, this now doesn't match anything at all, strangely. Not within while or within a for loop. Only thing I got working is like said within for with $_ as the match. Btw., thanks for the link to Death to Dot Star, the .*? is save in this place. Sorry that I didn't mention it before, maybe it's important: This is perl, v5.6.0 built for i386-linux -- Alfie	[reply]
Re: Re: Re: $1 doesn't reset? by andye (Curate) on Mar 20, 2001 at 17:56 UTC
alfie, my understanding is this (and I'm relying on more knowledgable monks to correct me if I'm misunderstanding): Working with $_, not $1, is the correct behaviour in the for loop. Because: - the regexp match produces a list - the for(each) loop cycles through each element of the list, assigning them to $_ as it goes. So... $1 doesn't contain each match in turn, because the regexp is only executed once, and the matches are put into $1 to $n, and into a list, and the loop goes round the list, aliasing $_ to each element in turn. If you want to use $1, then Corion's suggestion of \G should do the biz. But it looks to me as though the for loop and $_ would be more efficient. andy.	[reply]