python 协程

协程：
实现方式：
1：greenlet 早期模块
2：yield关键字
3：asyncio装饰器 p3.4
4：async await p3.5


greenlet 实现协程


from greenlet import greenlet




def func1():
    print(1)
    gr2.switch()
    print(2)
    gr2.switch()


def func2():
    print(3)
    gr1.switch()
    print(4)



gr1 = greenlet(func1)
gr2 = greenlet(func2)

gr1.switch() # 第一步，执行func1

# 1
# 3
# 2
# 4



yield 实现协程


# yield



def func1():
    yield  1
    yield  from func2()
    yield  2


def func2():
    yield 3
    yield 4



f1 = func1()

for item in f1:
    print(item)
# 1
# 3
# 4
# 2




asyncio 遇到io操作自动切换
coroutine过期了

import asyncio


@asyncio.coroutine
def func1():
    print(1)
    yield  from asyncio.sleep(1)
    print(2)


@asyncio.coroutine
def func2():
    print(3)
    yield from asyncio.sleep(2)
    print(4)


tasks = [
    asyncio.ensure_future(func1()),
    asyncio.ensure_future(func2()),
]

loop = asyncio.get_event_loop()
loop.run_until_complete(asyncio.wait(tasks))



import asyncio


async  def func1():
    print(1)
    await  asyncio.sleep(1)
    print(2)



async def func2():
    print(3)
    await asyncio.sleep(2)
    print(4)


tasks = [
    asyncio.ensure_future(func1()),
    asyncio.ensure_future(func2()),
]

loop = asyncio.get_event_loop()
loop.run_until_complete(asyncio.wait(tasks))

python 协程

原文：https://www.cnblogs.com/lzjloveit/p/14162322.html