prependOnceListener #
Adds a one-time listener function for an event to the beginning of the listeners array.
The next time that event is triggered, this listener is removed, and then invoked.
Arguments #
prependOnceListener(eventName, callback);| Argument | Type | Description |
|---|---|---|
eventName | string | The name of the event |
callback | function | Function to call when the event is triggered |
Return #
The KuzzleEventEmitter instance.
Usage #
const eventEmitter = new KuzzleEventEmitter();
eventEmitter.addListener("myEvent", () => console.log("listener1"));
eventEmitter.prependOnceListener("myEvent", () => console.log("listener2"));
// Prints:
// listener2
// listener1
eventEmitter.emit("myEvent");
// Prints: listener1
// (the listener function printing "listener2" as since been removed)
eventEmitter.emit("myEvent");