"""Zymb: An Asynchronous Python Communication Package
    Designed by Andrew Plotkin <erkyrath@eblong.com>
    Zymb home page: <http://eblong.com/zarf/zymb/>

The Python source code in this module, and its submodules, is
copyright 2005 by Andrew Plotkin. You may copy and distribute it
freely, by any means and under any conditions. You may incorporate
this code into your own software and distribute that, or modify this
code and distribute the modified version, as long as you retain a
notice in your software or documentation which includes this copyright
notice, this license, and the URL shown above.

Zymb is a Python framework for handling asynchronous communication and
events. In theory, any communication mechanism could be implemented as
a Zymb agent. In practice, I've got files, TCP sockets, and Jabber
instant messaging.

Zymb requires Python version 2.3 or later.

I do not have top-to-bottom documentation written. (Sorry.) However,
the modules are heavily commented. The comments are in the form of
docstrings, so you can either look at the source code, or use the
help() function from an interactive Python shell.

If you are new to Zymb, start by looking at the zymb.sched module --
in particular, the zymb.sched.Agent class and the zymb.sched.process()
function. You will also want to look at the Zymb example applications
(available at the URL above). They demonstrate using Zymb agents for
simple tasks.

* Version history:

- 1.2.7:
Fixed dumb bug when comparing (jid1 != jid2)

- 1.2.6:
Added a hook API to PresenceService, so that an application can customize
    presence stanzas as they're generated.
Added the Entity Capabilities (JEP-0115) URI to interface.py.

- 1.2.5:
Added a way to override the default parsing of Jabber-RPC value tags.
    (On a global basis only -- sorry.)

- 1.2.4:
Added a way to create a Jabber stream which communicates with a server
    different from the one in the JID. (This is necessary to deal with
    talk.google.com, which uses "name@gmail.com" JIDs.)
The Jabber agent now understands the concept of getting a resource from
    the server which is not the one it asked for.
Various other fixes for bugs which were uncovered by Google's Jabber
    implementation.

- 1.2.3:
Fixed the RPC service to disallow empty RPC replies. (I thought that was
    legal, but it isn't.) An RPC handler which returns None will now
    generate a True response.

- 1.2.2:
Added a way to customize the "RPC not found" response of the RPC service.
More comments.

- 1.2.1:
Adjusted the scheduler so that one network message's consequences are
    fully executed before the next message begins.
Added a keepalive service (exercises Jabber connection periodically).

- 1.2:
Implemented XML classes. Zymb now relies only on Python standard library
    modules.
Fixed bug in RPC service (arguments were wrapped in an extraneous array)

- 1.1:
The Jabber client now starts an XMPP session after binding, on
    servers that support the session feature.
Added simple presence service. (Just handles on and off.)

- 1.0:
Initial release. (Why start at 1.0 for a very incomplete release?
    Well, why not, really. It's not like "0.3" would be any more
    meaningful.)
"""

import sys
if (sys.hexversion < 0x2030000):
    raise Exception, 'zymb requires Python version 2.3 or later.'

__all__ = [
    'sched', 'fileagent', 'readlineagent', 'tcp', 'xmlagent', 'xmldata',
    'jabber'
]