(a) give up immediately, with a "stupid user" (or some such) message? (b) silently ignore all ts? (c) silently convert ts to us? (d) something else?
I think (b) and (c) are non-starters as they may do 'the wrong thing' leaving the user a booby trap for later on.
I imagine that the most likely causes for getting into that position are (1) "I meant U, not T" or (2) "I got confused and thought I was generating DNA", so I would suggest some kind of message which gets people on the correct path asap.
Cheers, Charlie -- Charlie Bond Professorial Fellow University of Western Australia School of Biomedical, Biomolecular and Chemical Sciences M310 35 Stirling Highway Crawley WA 6009 Australia [EMAIL PROTECTED] +61 8 6488 4406
