On Fri, Jan 25, 2013 at 10:35 AM, Аркадий Левин <poisonoff@gmail.com> wrote:

Hi all, i got strange error

If run this:

# -*- coding: UTF-8 -*-

import os import sys

from twisted.python import log from twisted.internet import reactor from twisted.internet.defer import Deferred, inlineCallbacks

@inlineCallbacks def _():

try: (yield Deferred()) except: log.err()

reactor.callLater(0, _) reactor.run()

i got exception "GeneratorExit" Why?!

This behavior isn't specific to inlineCallbacks. If you get rid of the reactor usage and the @inlineCallbacks decorator, and just call _().next(), you'll see the same behavior. http://docs.python.org/2.7/reference/expressions.html?highlight=yield%20expr... See the stuff about how .close() throws GeneratorExit into the generator. It is related to garbage collection. When a generator is garbage collected, its .close() method is called. Since you're keeping a reference to the Deferred in the generator itself in the working version, it's not being immediately closed because there's a circular reference. (I think?) -- Christopher Armstrong http://radix.twistedmatrix.com/ http://planet-if.com/

On Fri, Jan 25, 2013 at 10:35 AM, Аркадий Левин <poisonoff@gmail.com> wrote:

Hi all, i got strange error

If run this:

# -*- coding: UTF-8 -*-

import os import sys

from twisted.python import log from twisted.internet import reactor from twisted.internet.defer import Deferred, inlineCallbacks

@inlineCallbacks def _():

try: (yield Deferred()) except: log.err()

reactor.callLater(0, _) reactor.run()

i got exception "GeneratorExit" Why?!

This behavior isn't specific to inlineCallbacks. If you get rid of the reactor usage and the @inlineCallbacks decorator, and just call _().next(), you'll see the same behavior. http://docs.python.org/2.7/reference/expressions.html?highlight=yield%20expr... See the stuff about how .close() throws GeneratorExit into the generator. It is related to garbage collection. When a generator is garbage collected, its .close() method is called. Since you're keeping a reference to the Deferred in the generator itself in the working version, it's not being immediately closed because there's a circular reference. (I think?) -- Christopher Armstrong http://radix.twistedmatrix.com/ http://planet-if.com/