replace abc with 123

#!/usr/bin/env perl

use strict;
use warnings;
our (%replace_list);

sub BEGIN {
    our %replace_list;
    $replace_list{'a'..'z'} = (1..9, map {0} 1..17)
}

sub replace_abc_123 {
    my $string = shift;

    my $output = "";
    for my $e (split //, $string) {
        if ($e =~ /[[:alpha:]]/) {
            $output .= $replace_list{lc $e};
        }
        else {
            $output .= $e
        }
    }

    return $output;
}

while (my $line = <DATA>) {
    $line =~ s{rename ([\w_]+) "([\w\.]+)"}
              {"rename " . replace_abc_123($1) .
               " \"" . replace_abc_123($2) . "\"" }e;
    $line =~ s{instanceRef ([\w_]+)}
              {"instanceRef " . replace_abc_123($1)}e;
    print "$line";
}

__END__
(port I0 (direction INPUT))
(instance (rename ABC_1def "CBA.gh3") (viewRef X)
(portRef I0 (instanceRef ABC_1def))
(portRef I1 (instanceRef iJk_1def))
(port LO (direction OUTPUT))
(portRef O (instanceRef ABC_1def))