- Moved abs_def to drule.ML
- elim_defs now takes a boolean argument which controls the automatic
expansion of theorems mentioning constants whose definitions are
eliminated
Defs = Types +
consts nand, exor :: gate
defs nand_def "nand A B == ~(A & B)"
exor_def "exor A B == A & ~B | ~A & B"
end