Popular recipes tagged "subscribe" but not "descriptor"http://code.activestate.com/recipes/tags/subscribe-descriptor/2012-12-06T19:23:11-08:00ActiveState Code RecipesFlexible observer pattern implementation (Python)
2012-12-06T19:23:11-08:00Glenn Eychanerhttp://code.activestate.com/recipes/users/4172294/http://code.activestate.com/recipes/576962-flexible-observer-pattern-implementation/
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Python
recipe 576962
by <a href="/recipes/users/4172294/">Glenn Eychaner</a>
(<a href="/recipes/tags/event/">event</a>, <a href="/recipes/tags/observer/">observer</a>, <a href="/recipes/tags/pattern/">pattern</a>, <a href="/recipes/tags/publish/">publish</a>, <a href="/recipes/tags/subscribe/">subscribe</a>, <a href="/recipes/tags/threadsafe/">threadsafe</a>).
Revision 16.
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<p>A simple, flexible, general-purpose observer pattern.</p>
<p>Observers can be callable objects or objects with a particular named method (handle_notify() by default). Events can be any object, and observers can select which events they are interested in receiving. Support for a number of different types of lightweight event objects is included.</p>
Yet another signal/slot implementation in Python (Python)
2008-09-01T23:21:28-07:00Thiago Marcos P. Santoshttp://code.activestate.com/recipes/users/4166797/http://code.activestate.com/recipes/576477-yet-another-signalslot-implementation-in-python/
<p style="color: grey">
Python
recipe 576477
by <a href="/recipes/users/4166797/">Thiago Marcos P. Santos</a>
(<a href="/recipes/tags/observer/">observer</a>, <a href="/recipes/tags/publish/">publish</a>, <a href="/recipes/tags/signal/">signal</a>, <a href="/recipes/tags/slot/">slot</a>, <a href="/recipes/tags/subscribe/">subscribe</a>, <a href="/recipes/tags/weakref/">weakref</a>).
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<p>This code snippet was based on the nice <a href="http://code.activestate.com/recipes/439356/">recipe 439356</a> made by Patrick Chasco. My implementation supports only class methods callbacks. I'm keeping the idea of use weakrefs to avoid the interpreter keep the object allocated because the signal is registered (i.e. the signal object holds a reference to callback method). IMO the usage of WeakValueDictionary made the code smaller and clear and also are maintenance-free (when the object is collect by the garbage collector the signal is automatically unregistered). </p>