The function used to check equality between different values. This can be manually set at any time to change the function used.
Protected ReadonlylistenerThis is necessary so we can fire listeners that listen directly to the value, not the emitted event.
ReadonlyvalueThe value currently contained with the observable.
Do not set this directly: use setValue instead. (If you try to set this value directly, it
won't fire listeners which defeats the entire purpose of using an observable.
Clean up all listeners and any other internal state.
ProtecteddispatchDispatch a typed event. Causes all attached listeners listening to this event to be fired.
The number of listeners that were fired.
Get a count of all currently attached listeners. If a listener is removed, it will no longer be counted.
Listen to changes in the observable's value.
If true, the callback will immediately be fired with whatever the current value is.
The callback to fire when a new value is set on the observable.
A callback to remove the listener.
Listen to any event omitted by the observable rather than just the value changing.
Optionaloptions: PartialWithUndefined<{}>A callback to remove the listener.
Remove all currently attached event listeners.
The number of listeners that were removed.
Removes a listener from the observable.
true if the callback was removed. false if the callback was not removed (meaning
it was never added in the first place).
Set a new value to the observable. The new value will only be set and listeners will only be
fired if the new value is not equal to the current value ("equal" determined by the
equalityCheck constructor parameter) or if equality checking is disabled.
A simple observable with a single value which can be set via
.setValue()and a listen method. Before a value is set, it is checked for equality with the current value. If they are equal, the value is not set. Equality checking can be turned off by passingundefinedas theequalityCheckconstructor parameter or by passing a different equality check callback.