- Now uses Orderings as parent theory - "'a set" is now just a type abbreviation for "'a => bool" - The instantiation "set :: (type) ord" and the definition of (p)subset is no longer needed, since it is subsumed by the order on functions and booleans. The derived theorems (p)subset_eq can be used as a replacement. - mem_Collect_eq and Collect_mem_eq can now be derived from the definitions of mem and Collect. - Replaced the instantiation "set :: (type) minus" by the two instantiations "fun :: (type, minus) minus" and "bool :: minus". The theorem set_diff_eq can be used as a replacement for the definition set_diff_def - Replaced the instantiation "set :: (type) uminus" by the two instantiations "fun :: (type, uminus) uminus" and "bool :: uminus". The theorem Compl_eq can be used as a replacement for the definition Compl_def. - Variable P in rule split_if must be instantiated manually in proof of split_if_mem2 due to problems with HO unification - Moved definition of dense linear orders and proofs about LEAST from Orderings to Set - Deleted code setup for sets

Deleted instance "set :: (type) power" and moved instance "fun :: (type, type) power" to the beginning of the theory

split_beta is now declared as monotonicity rule, to allow bounded quantifiers in introduction rules of inductive predicates.