a coroutine implementation that can work with tornado.ioloop

gistfile1.py

#!/usr/bin/env python

import tornado.ioloop

class Coroutine(object):
  """
  a coroutine implementation that can work with tornado.ioloop

  def generator():
    print('A')
    yield
    print('B')
  def finished():
    print('Z')

  co = Coroutine(generator)
  co(finished)
  --
  A
  B
  Z
  """
  def __init__(self, generator, io_loop=None):
    self.generator = generator
    self.iterator = None
    self.io_loop = tornado.ioloop.IOLoop.instance() if io_loop is None else io_loop
    self.alive = True

  def __call__(self, *args):
    try:
      if self.iterator is None:
        self.iterator = self.generator(*args)
        response = next(self.iterator)
      else:
        if 0 < len(args):
          response = self.iterator.send(*args)
        else:
          response = next(self.iterator)
      self.io_loop.add_callback(self)
    except StopIteration:
      self.alive = False

# vim:set ft=python :