- eliminated thin_leading_eqs_tac
- gen_hyp_subst_tac now uses asm_lr_simp_tac instead of asm_full_simp_tac,
in order to avoid divergence of new simplifier
Gate = FOL +
consts nand,xor :: "[o,o] => o"
rules nand_def "nand(P,Q) == ~(P & Q)"
xor_def "xor(P,Q) == P & ~Q | ~P & Q"
end