#!/usr/bin/perl -wT
use strict;
use Test;
BEGIN { plan tests => 345 }

for my $num (-56789, -300, -1, 0..100, 5345, 6574572, 23457356) {
  ok( is_integer($num) );
  my $string = "$num";
  ok( not is_integer($string) );
}

for my $string ((map { chr($_) } 0..127), 'dog', 'cat', 'mouse') {
  ok( not is_integer($string) );
}

sub is_integer { ~$_[0] !~ /\D/ }