- Datatype package now also supports arbitrarily branching datatypes
(using function types).
- Added new simplification procedure for proving distinctness of
constructors.
- dtK is now a reference.
Defs = Types +
consts nand, exor :: gate
defs nand_def "nand A B == ~(A & B)"
exor_def "exor A B == A & ~B | ~A & B"
end