in reply to $1 doesn't reset?

I think the problem is that the array you expect to get back from the regular expression is broken. I slightly altered your code.

thus: (I think it does the same thing.) 

$_='axxbcaxbagaxbacba';
for (m/a(.*?)b/g) {
    print "$a\n";
}

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It don't work...so, I went right back to basics: 
$_='axxbcaxbagaxbacba';
foreach my $a (m/a(.*?)b/g) {
    print "$a\n";
}

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In the second example the return of each item from an array created by the regular expression is explicit and it works.

P.S. That is a non greedy .* isn't it? 

--
Brother Frankus.

Replies are listed 'Best First'.
Re: $1 doesn't reset?
by alfie (Pilgrim) on Mar 20, 2001 at 15:57 UTC
    Thanks for this workaround, too. But it still doesn't explain why $1 isn't filled in each iteration with the match but only in the first....
    --
    Alfie
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      I failed to make my point: I think it is to do with the array is being forced to a scalar, i.e. look at the loop, not the regex :)

      Yoda: "work-arounds, crufts, kludges...the dark side are they. Easily 
+they flow, quick to join you in times of trouble.
Luke: "Is the dark side more powerful?"
Yoda: "No..no....no, quicker, easier, more seductive"
Luke: "How am I to know the good side from bad?"
Yoda: "Once you start along the dark path, forever will it cloud your 
+change requests"

      [download]

      --
      Brother Frankus.

      Edit 2001-03-20 by tye (changed <pre> to <code>)

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      I'll take a crack at this one, since it gave me the same kind of problems when I started using regexps as loop controls. Using brother frankus' example :
      $_='axxbcaxbagaxbacba';
foreach my $a (m/a(.*?)b/g) {
    print "$a\n";
}

      [download]
      OK, so, from perlman :
      The foreach modifier is an iterator: For each value in EXPR, it aliases $_ to the value and executes the statement
      So, right away, we see that foreach doesn't care about, or understand $1 and company at all. It only knows about its control variable ($a, in this case) and its list : (m/a(.*?)b/g).
      So what's the for statement's list? It's generated from m/a(.*?)b/g. And, as perlop states,
      (m//) ... in a list context returns a list consisting of the subexpressions matched by the parentheses in the pattern, i.e., ($1, $2, $3...)
      So, with this regexp, you get an anonymous list of 4 elements. It's like writing 
      foreach my $a ($1, $2, $3, $4) {

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      by the time the code in the loop's running, the regexp has run and returned a list of values that foreach will process.
      I hope that makes things a little clearer, this gave me trouble for a while, and hopefully this explanation will minimize the trouble it gives you.
      update see below... sometimes convenient variables aren't good for practical use.
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        But... please don't get in the habit of using $a or $b as variables! These are magical when used with sort...

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In Section Seekers of Perl Wisdom