Generic Event Handling

Enables events on an object. slots should contain symbol-names of events the object will implement. For example:

(define thing 'thing)
;Value: thing

(events:add-support! thing 'event1 'event2)
;Value: ok

(events:register-handler! thing 'event1 (lambda () (println "event1 handler A reporting")))
;Unspecified return value

(events:register-handler! thing 'event1 (lambda () (println "event1 handler B reporting")))
;Unspecified return value

(events:register-handler! thing 'event2 (lambda () (println "event2 handler A reporting")))
;Unspecified return value

(events:register-handler! thing 'event2 (lambda () (println "event2 handler B reporting")))
;Unspecified return value

(events:raise thing 'event1)
event1 handler B reporting
event1 handler A reporting
;Value: ok

(events:raise thing 'event1)
event1 handler B reporting
event1 handler A reporting
;Value: ok

(events:raise thing 'event2)
event2 handler B reporting
event2 handler A reporting
;Value: ok

(events:raise thing 'event1)
event1 handler B reporting
event1 handler A reporting
;Value: ok

Checks whether an object supports the given event

Registers a handler for an even with an object. See events:add-support! for an example.

Raises an event. See events:add-support! for an example.