The problem with using two regexes is: if it matches and then gets rejected, your pos counter is still incremented. Say you match a string of 6 chars, QGYNNN. What you want from that is QGYNN (right, OP?), but what happens is that all six characters get tossed.

That brings me to a flaw in my proposed solution: it will only give you QGYN from the above input. Needs some tweaking.

Caution: Contents may have been coded under pressure.

In reply to Re^4: Perl regular expression for amino acid sequence by Roy Johnson
in thread Perl regular expression for amino acid sequence by seaver

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