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event_disable(+EventHandle)
Disable the given event
- EventHandle
- An event handle
Description
	The given event is disabled.  A disabled events behaves as if its
	handler was the goal 'true':
	
	- Retrieving the goal using event_retrieve/3 returns 'true'
- When the event is raised (e.g. posted via event/1), nothing happens
- If the event gets disabled after it was raised, but before its handler
	    execution has started, handler execution will be suppressed.
	Note that disabling and enabling events are nonlogical operations
	which are not undone on backtracking.
    
    
Modes and Determinism
Exceptions
- (4) instantiation fault 
- EventHandle is un-instantiated
- (5) type error 
- EventHandle is not a handle
Examples
    ?- event_create(writeln(hello), [], E),
       event_disable(E), writeln(disabled),
       event(E),	% does nothing
       event_enable(E), writeln(enabled),
       event(E).
    disabled
    enabled
    hello
    
See Also
event_create / 3, event / 1, event_enable / 1, event_retrieve / 3