54 typedef enum { low = 0, high, undefined } signal_t;  enumerator
337     toggle(oneapi::tbb::flow::graph& g) : my_graph(g), state(undefined), toggle_node(g) {}  in toggle()
340               state(undefined),  in toggle()
372         buffer_body() : state(undefined), touched(false) {}  in buffer_body()
396         not_body() : port(undefined), touched(false) {}  in not_body()
426         and_body() : state(undefined), touched(false) {  in and_body()
429                 ports[i] = undefined;  in and_body()
440                 else if (ports[i] == undefined && new_state != low) {  in operator ()()
441                     new_state = undefined;  in operator ()()
470         or_body() : state(undefined), touched(false) {  in or_body()
473                 ports[i] = undefined;  in or_body()
484                 else if (ports[i] == undefined && new_state != high) {  in operator ()()
485                     new_state = undefined;  in operator ()()
514         xor_body() : state(undefined), touched(false) {  in xor_body()
517                 ports[i] = undefined;  in xor_body()
524                 if (ports[i] == undefined) {  in operator ()()
525                     new_state = undefined;  in operator ()()
565         nor_body() : state(undefined), touched(false) {  in nor_body()
568                 ports[i] = undefined;  in nor_body()
579                 else if (ports[i] == undefined && new_state != high) {  in operator ()()
580                     new_state = undefined;  in operator ()()
619                 if (state != undefined && report_changes) {  in operator ()()
640               state(undefined),  in led()
646               state(undefined),  in led()
654         state = undefined;  in operator =()
691                 ports[i] = undefined;  in digit_body()