#!/usr/bin/perl -ln

use strict;
use warnings;

sub expand;
sub doit;

print for expand $_;

sub expand {
    local $_=shift;
    return doit $`, (split /:/, $1), $' if /\{([\w:]+)\}/;
    return doit $`, $1 .. $2 , $' if /\[(\w+):(\w+)\]/;
    $_;
}

sub doit {
    my ($pre,$post)=(shift,pop);
    map { my $pre=$pre . $_; 
        map $pre . $_, expand $post } @_;
}

__END__