2|S, in my mind, should have alternated chars 2 or S, not 2 or (0-many other chars) followed by S.

In isolation, yes. But you have used it in combination with other elements without limiting the alternation.

Far easier if you just want alternate characters to use a character class, eg: /^.T[2S]/

HTH.

In reply to Re: Perl alternation regex looks ok to me? by hippo
in thread Perl alternation regex looks ok to me? by misterperl

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