python实现异步过程asyncio
异步发展过程
1.用greenlet
from greenlet import greenlet
def fun1():
print('1')
def fun2():
print('2')
g1=greenlet(fun1)
g2=greenlet(fun2)
g1.switch()
2.用yield
3.用asyncio
import asyncio
@asyncio.coroutine
def fun3():
yield from asyncio.sleep(2)
print('3')
tasks=[
asyncio.ensure_future(fun3())
]
asyncio.get_event_loop().run_until_complete(asyncio.wait(tasks))
第三阶段也就是上面的第三条最后一步，随着python不断更新对第三阶段的的最后一步实现了简写
async def main():
tasks = [
asyncio.ensure_future(fun4())
]
done,pending= await asyncio.wait(tasks,timeout=None)
print(done)
# 此方法 在run方法中实get_event_loop().run_until_complete(asyncio.wait(tasks))
asyncio.run(main())