#!/usr/bin/env perl -l

use strict;
use warnings;

my @tests = qw{
    one one.two one.two.three four.five.six.seven one. one-two
    .one .one. . .. .@. one.good.egg one.-bad-.egg
};
print "'$_': ", grep(! /^\w+$/, split /\./, $_, -1) ? 'bad' : 'good' for @tests;