while (<DATA>) {
	my ($host,$comment)
		= m{^ \s* (\w+) (?: \s+ \#+ (.*) | \s* ) $}x
		#OR:
		# m{^ \s* (\w+) (?: \s+ (?: \#+ (.*) )? )? $}x
		or die "failed to parse '$_'";
	$hosts{$host} = $comment//'';
}