@asyncio.coroutine yield from 协程

Asyncio Finite State Machine

import asyncio
import time
from random import randint

@asyncio.coroutine
def StartState():
print("Start State called \n")
input_value = randint(0, 1)
time.sleep(1)
if (input_value == 0):
result = yield from State2(input_value)
else:
result = yield from State1(input_value)
print("Resume of the Transition : \nStart State calling " + result)

@asyncio.coroutine
def State1(transition_value):
outputValue = str("State 1 with transition value = %s \n" % transition_value)
input_value = randint(0, 1)
time.sleep(1)
print("...Evaluating...")
if input_value == 0:
result = yield from State3(input_value)
else :
result = yield from State2(input_value)
result = "State 1 calling " + result
return outputValue + str(result)

@asyncio.coroutine
def State2(transition_value):
outputValue = str("State 2 with transition value = %s \n" % transition_value)
input_value = randint(0, 1)
time.sleep(1)
print("...Evaluating...")
if (input_value == 0):
result = yield from State1(input_value)
else :
result = yield from State3(input_value)
result = "State 2 calling " + result
return outputValue + str(result)

@asyncio.coroutine
def State3(transition_value):
outputValue = str("State 3 with transition value = %s \n" % transition_value)
input_value = randint(0, 1)
time.sleep(1)
print("...Evaluating...")
if (input_value == 0):
result = yield from State1(input_value)
else :
result = yield from EndState(input_value)
result = "State 3 calling " + result
return outputValue + str(result)

@asyncio.coroutine
def EndState(transition_value):
outputValue = str("End State with transition value = %s \n" % transition_value)
print("...Stop Computation...")
return outputValue

if name == "main":
print("Finite State Machine simulation with Asyncio Coroutine")
loop = asyncio.get_event_loop()
loop.run_until_complete(StartState())