I think that's less efficient than: /^(?=[smtwhfa]*$)(?!.*(.).*\1)/ but I'm too busy right now to find out.
_____________________________________________________
Jeff[japhy]Pinyan: Perl, regex, and perl hacker, who'd like a job (NYC-area)
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

In reply to Re: Re: Regex (lookahead) Confusion by japhy
in thread Regex (lookahead) Confusion by ChrisR

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