while ((say "Input template string:") && ($string = <>) ) {
    while ((say "Input pattern:") && ($pattern = <STDIN>)) {

[download]

That should be: 

while ((say "Input template string:") && defined(my $string = <>) ) {
    while ((say "Input pattern:") && defined(my $pattern = <STDIN>)) {

[download]

If you enter "0" for either $string or $pattern your loop will end prematurely.

In reply to Re: Regex practice script by jwkrahn
in thread Regex practice script by kindlychung

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