val zero : int signalval one : int signalval minus_one : int signalval (~-) : int signal -> int signalval succ : int signal -> int signalval pred : int signal -> int signalval (+) : int signal -> int signal -> int signalval (-) : int signal -> int signal -> int signalval (*) : int signal -> int signal -> int signalval (mod) : int signal -> int signal -> int signalval abs : int signal -> int signalval max_int : int signalval min_int : int signalval (land) : int signal -> int signal -> int signalval (lor) : int signal -> int signal -> int signalval (lxor) : int signal -> int signal -> int signalval (lnot) : int signal -> int signalval (lsl) : int signal -> int signal -> int signalval (lsr) : int signal -> int signal -> int signalval (asr) : int signal -> int signal -> int signal