Sequence function predicate arg order

[Moon@SCRC-STONY-BROOK.ARPA]

    Date: Friday, 7 September 1984, 15:34-EDT
    From: Bernard S. Greenberg <BSG at SCRC-TENEX>

    The following issue was encountered today by David Andre.  He wanted
    to find the position of first element in a string which was not an element of a list
    he had in hand....
    Possible outcomes:
      1.  Magic keyword to sequence functions to reverse test arg order?  ECCH!
      2.  More string-specific primitives.
      3.  Maybe he should have said :test #'(lambda (x y)(member y x)).

Among your alternatives, I'd prefer #3, i.e. write
	(position list sequence :test-not #'(lambda (x y) (member y x)))
I would actually write
	(position-if-not #'(lambda (item) (member item list)) sequence)