This crate exports traits useful for a few design patterns common in GUI development, with abstractions built only using the standard library, such as:
Verify Implemented by objects that most uphold some condition.
Callbacks/ValuedCallbacks Synchonous Signal/Slots (late binding) mechanism, built on RefCell/Rc.
Inherit Java-style inheritance trait.
Transition Implements the typestate pattern.
A few other traits are still a work in progress.