basic variety of
HIPEventedProperty has no constraints on the type, but performs no duplicate
value checks before firing subscribers.
HIPEventSourceWithValue for more methods.
Stored value of the property. Whenever this changes, all subscribers are fired unless their associated objects have been deallocated.
open var value: T
public init(_ initialValue: T)
Initial value of the property
true(default), subscribers are not fired when
valueis set if it is not
==to the previous value.