#!/usr/bin/perl -w
use strict;
use Term::ReadLine;

my $term = new Term::ReadLine 'regexp Smode';
my $OUT = $term -> OUT || \*STDOUT;
my %p;

while (1){
    for my $key (qw/string replace with suffix/){
        $p{$key} = $term->readline("\u$key: ");
        exit if $p{$key} =~ /^(?:quit|exit)$/i;
    }
    eval "\$p{string} =~ s/\$p{replace}/\$p{with}/$p{suffix}";
    print $OUT $@ ? "ERROR: $@\n" : "$p{string}\n\n";
}