I'm sure that there's a more compact way to do this, but I think that this does what you are looking for.

I'm also assuming that you meant that each line of your input file had a different number of "dash pairs" such as: 

 --- beginning of data ---
1-2,3-4,2-5
2-1,2-5
3-5,1-9,2-2,4-8
 --- end of data ---

use warnings;
use strict;

while (<>) {
    chomp;
    my @dashpairs = split(/,/);
    foreach my $dashpair (@dashpairs) {
        my ($num1, $num2) = split(/-/,$dashpair);
        print "$num1 - $num2\n";
    }
}

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In reply to Re: How to handle a variable number of results from split()? by AReed
in thread How to handle a variable number of results from split()? by Anonymous Monk

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