qurtus 2 , state machine

qurtus 2 综合后state machine viewer 里的(！cur_state).(cur_state).(！write) + (cur_state).(！cur_state).(！length[0]).(！read).(！write) + (cur_state).(！cur_state).(length[0]).(！length[1]).(！length[2]).(！length[3]).(！write) + (cur_state).(！cur_state).(length[0]).(！length[1]).(！length[2]).(length[3]).(！read).(！write) + (cur_state).(！cur_state).(length[0]).(！length[1]).(length[2]).(！read).(！write) + (cur_state).(！cur_state).(length[0]).(length[1]).(！read).(！write) + (cur_state).(cur_state).(！write)怎么理解?那个点（.）是什么意思?感叹号是非?加号是或?不太理解。谢谢！

study。