in reply to Specifying how many times a regex should work

I can see at least two things wrong. First, the inner for loop overwrites $_. Therefore your regex is matching against the strings "0" and "1" and not against the record from the input file.

Also, without the /g modifier on the match, you will simply match the same thing twice. The /g forces the next match to start looking where the last match left off. 

while (<FH>) {
    chomp;
    my $record = $_;
    for (0 .. 1) {
        $record =~ m/ ... /xg
            and print "matched: $1\n";
    }
}

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Or you may be better off getting all matches at once by using /g in list context. Then you can just use a slice to get the ones you want, and not have to fuss around with a for loop. I think the readability is greatly improved. 
while (<FH>) {
    chomp;
    my @all_matches = m/ ... /xg;
    my @first_few   = @all_matches[0 .. 1];
}

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blokhead

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Re^2: Specifying how many times a regex should work
by coldfingertips (Pilgrim) on Jun 05, 2004 at 19:48 UTC
    Thanks for your help. I finally was able to get it to work with yoru first example but ran into *another* problem. I spent a few hours trying different methods to do this but nothing seems to work. The original script only saved the regex information to the variable but I need the entire contents of each separated data to be stored so I can use it again.

    I'm only using regexes so I can resort the data. I'm trying to get the phone1, phone2, price, everything else in that order so I really need to store ALL of that paragraph stored so I can apply my s///s and other regexes to it.

    Does this make any sense or am I in too deep and this won't ever work?

[reply]

      I'd tackle your original problem this way. I've used simplified regexes to demonstrate the technique. They seem to work pretty well on your original sample data, but you can adapt them to your needs. 

      #! perl -slw
use strict;

local $/= "\n====\n";

while( <DATA> ) {
    ## Clear out residual values from global vars
    our( $no1, $no2, $price ) = ( undef ) x 3;
    
    tr[\n][ ]; ## Strip newlines
    
    ## Extract the cash value into $price
    s[ ( \$[\d,]+ (?:\.\d+)? ) (?{ $price = $^N                   }) ]
+[ ]x;
    
    ## Grab the first 1 or 2 telephone numbers
    s[ ( [\d-]{12}           ) (?{ $no1 ? $no2 = $^N : $no1 = $^N }) ]
+[ ]xg;
    
    ## join them together in the requisite order and output
    print join ', ', $no1||'n/a', $no2||'n/a', $price||'n/a', $_;
}

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      Examine what is said, not who speaks.
      "Efficiency is intelligent laziness." -David Dunham
      "Think for yourself!" - Abigail
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