David, you were correct the first time and your second example is fine.
] can be the first character in a class without being escaped.
H:\>perl -e "$_='a';/[]a]/?print 'Y':print 'N'"
Y
H:\>
On an XP box (which is why you see the reversed quote notation). I also believe you're absolutely correct about the hyphen being acceptable as the last character (it's not "underscore to nothing").
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s''limp';@p=split '!','n!h!p!';s,m,s,;$s=y;$c=slice @p1;so brutally;d;$n=reverse;$c=$s**$#p;print(''.$c^chop($n))while($c/=$#p)>=1;
