(Resend to change to plain text format)
Hi, How about this: (de singleLetter? (item) (if (and (=1 (length item)) (or (low? item) (upp? item))) 1 NIL)) This returns 1 if true then NIL for false. But if you just need NIL for false and then the letter itself for true, then can be shorten into this: (de singleLetter? (item) (and (=1 (length item)) (or (low? item) (upp? item)))) BR, geo -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe