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in reply to $1 doesn't reset?
in thread $1 doesn't reset?

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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Yoda: A jedi warrior, you seek? hmm?
by frankus (Priest) on Mar 20, 2001 at 16:13 UTC

    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"

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    --
    Brother Frankus.

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

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(boo) Using regexps as lists in loops
by boo_radley (Parson) on Mar 20, 2001 at 19:01 UTC
    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";
}

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    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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