简单介绍Python中利用生成器实现的并发编程

#coding=utf-8
import time
import sys
# 生产者
def produce(l):
  i=0
  while 1:
    if i < 5:
      l.append(i)
      yield i
      i=i+1
      time.sleep(1)
    else:
      return
   
# 消费者
def consume(l):
  p = produce(l)
  while 1:
    try:
      p.next()
      while len(l) > 0:
        print l.pop()
    except StopIteration:
      sys.exit(0)
l = []
consume(l)

import stackless
import urllib2
def output():
  while 1:
    url=chan.receive()
    print url
    f=urllib2.urlopen(url)
    #print f.read()
    print stackless.getcurrent()
   
def input():
  f=open('url.txt')
  l=f.readlines()
  for i in l:
    chan.send(i)
chan=stackless.channel()
[stackless.tasklet(output)() for i in xrange(10)]
stackless.tasklet(input)()
stackless.run()