介绍Python的Tornado框架中的协程异步实现原理

def test():
yield 1

>>> test()
<generator object test at 0x100b3b320>

>>> t = test()
>>> t.next()
1

>>> def test():
a = yield
print(a)

#!/usr/bin/env python
# -*- coding:utf-8 -*-

from __future__ import absolute_import, print_function, division, with_statement
 
def loop1():
""" 循环1负责抛出一个函数和对应的参数, 并接收结果
"""
a = 0
ret = 1
while True:
ret = yield sum, [a, ret]
a, ret = ret, a
print("Loop1 ret", ret)

def loop2():
""" 循环2 负责接收函数并计算结果, 然后 yield 出结果
"""
while True:
func, args = yield
yield func(args)
print("Loop2")
 
 
l1 = loop1()
l2 = loop2()
tmp = l1.next()
 
for i in range(10):
l2.next()
ret = l2.send(tmp)
tmp = l1.send(ret)

#!/usr/bin/env python
# -*- coding:utf-8 -*-
 
from __future__ import absolute_import, print_function, division, with_statement
 
from tornado import gen
from tornado import web
from tornado import httpclient
 
 
class ActionHandler(web.RequestHandler):
 
@gen.coroutine
def get(self):
response = yield httpclient.AsyncHTTPClient().fetch("http://www.linuxzen.com")
 
# ...