Logical. If the Event already exists, should I overwrite it? If TRUE
then yes, without warning. If FALSE (default) then no, throw an error.
Value
Nothing good.
Details
Add a new event to a registry. If an Event of that name already
exists then if overwrite is not set then an error is thrown, and
if overwrite is set then the contents of the old Event are simply replaced.
Use add.handler to add a handler to an existing Event.