Now possibility_tac and basic_possibility_tac are explicit functions, in order
to delay the evaluation of \!simpset
(* Title: HOLCF/Sprod2.thy
ID: $Id$
Author: Franz Regensburger
Copyright 1993 Technische Universitaet Muenchen
Class Instance **::(pcpo,pcpo)po
*)
Sprod2 = Sprod1 +
instance "**"::(pcpo,pcpo)po
(refl_less_sprod, antisym_less_sprod, trans_less_sprod)
end