Ember.js mixin/object internals

I'm trying to build a little extension for Ember that would have been set up though the helper function, like computed/observer/on. As far as I understand, this helper function just adds property to function object: http://ift.tt/2aPxqvs

The question is how to find that property on mixin initialization. Related logic in mixin prototype looks pretty complicated and I can't understand how exactly they retrieve properties and check if __ember_listens/observes__ set up to do stuff with right properties.

Some easy (and efficient) way to enumerate through the properties of the object?