New unified treatment of sequent calculi by Sara Kalvala
combines the old LK and Modal with the new ILL (Int. Linear Logic)
(* Title: FOL/ex/IffOracle
ID: $Id$
Author: Lawrence C Paulson, Cambridge University Computer Laboratory
Copyright 1996 University of Cambridge
Example of how to declare an oracle
*)
IffOracle = "declIffOracle" + FOL +
oracle mk_iff_oracle
end