I was referring to John McCarthy's definition of a list. IIRC, Common lisp's list type includes both proper and unproper lists. (typep (cons 1 2) 'list) evaluat

I was referring to John McCarthy's definition of a list. IIRC, Common lisp's list type includes both proper and unproper lists. (typep (cons 1 2) 'list) evaluates to true but (length (cons 1 2)) throws a type error (not a list).