Adding in IEventEmitter

src/event-emitter-type.ts → src/event-emitter.ts

@@ -1,4 +1,4 @@
-type EventEmitterType = {
+export type IEventEmitter = {
 	/**
 	 * Registers a listener for the specified event.
 	 *
@@ -11,7 +11,7 @@ type EventEmitterType = {
 	 *   console.log(message);
 	 * });
 	 */
-	on(eventName: string | symbol, listener: (...arguments_: any[]) => void): EventEmitterType;
+	on(eventName: string | symbol, listener: (...arguments_: any[]) => void): IEventEmitter;
 
 	/**
 	 * Alias for `on`. Registers a listener for the specified event.
@@ -20,7 +20,7 @@ type EventEmitterType = {
 	 * @param listener - A callback function that will be invoked when the event is emitted.
 	 * @returns The current instance of EventEmitter for method chaining.
 	 */
-	addListener(eventName: string | symbol, listener: (...arguments_: any[]) => void): EventEmitterType;
+	addListener(eventName: string | symbol, listener: (...arguments_: any[]) => void): IEventEmitter;
 
 	/**
 	 * Registers a one-time listener for the specified event. The listener is removed after it is called once.
@@ -34,7 +34,7 @@ type EventEmitterType = {
 	 *   console.log('The connection was closed.');
 	 * });
 	 */
-	once(eventName: string | symbol, listener: (...arguments_: any[]) => void): EventEmitterType;
+	once(eventName: string | symbol, listener: (...arguments_: any[]) => void): IEventEmitter;
 
 	/**
 	 * Removes a previously registered listener for the specified event.
@@ -46,7 +46,7 @@ type EventEmitterType = {
 	 * @example
 	 * emitter.off('data', myListener);
 	 */
-	off(eventName: string | symbol, listener: (...arguments_: any[]) => void): EventEmitterType;
+	off(eventName: string | symbol, listener: (...arguments_: any[]) => void): IEventEmitter;
 
 	/**
 	 * Alias for `off`. Removes a previously registered listener for the specified event.
@@ -55,7 +55,7 @@ type EventEmitterType = {
 	 * @param listener - The specific callback function to remove.
 	 * @returns The current instance of EventEmitter for method chaining.
 	 */
-	removeListener(eventName: string | symbol, listener: (...arguments_: any[]) => void): EventEmitterType;
+	removeListener(eventName: string | symbol, listener: (...arguments_: any[]) => void): IEventEmitter;
 
 	/**
 	 * Emits the specified event, invoking all registered listeners with the provided arguments.
@@ -90,7 +90,7 @@ type EventEmitterType = {
 	 * @example
 	 * emitter.removeAllListeners('data');
 	 */
-	removeAllListeners(eventName?: string | symbol): EventEmitterType;
+	removeAllListeners(eventName?: string | symbol): IEventEmitter;
 
 	/**
 	 * Returns an array of event names for which listeners have been registered.
@@ -138,7 +138,7 @@ type EventEmitterType = {
 	 *   console.log('This will run first.');
 	 * });
 	 */
-	prependListener(eventName: string | symbol, listener: (...arguments_: any[]) => void): EventEmitterType;
+	prependListener(eventName: string | symbol, listener: (...arguments_: any[]) => void): IEventEmitter;
 
 	/**
 	 * Adds a one-time listener to the beginning of the listeners array for the specified event.
@@ -152,5 +152,5 @@ type EventEmitterType = {
 	 *   console.log('This will run first and only once.');
 	 * });
 	 */
-	prependOnceListener(eventName: string | symbol, listener: (...arguments_: any[]) => void): EventEmitterType;
+	prependOnceListener(eventName: string | symbol, listener: (...arguments_: any[]) => void): IEventEmitter;
 };

src/eventified.ts

@@ -1,6 +1,8 @@
+import { type IEventEmitter } from './event-emitter.js';
+
 export type EventListener = (...arguments_: any[]) => void;
 
-export class Eventified {
+export class Eventified implements IEventEmitter {
 	_eventListeners: Map<string, EventListener[]>;
 	_maxListeners: number;
 
@@ -14,11 +16,12 @@ export class Eventified {
 	}
 
 	// Add an event listener
-	public addListener(event: string, listener: EventListener): void {
+	public addListener(event: string, listener: EventListener): IEventEmitter {
 		this.on(event, listener);
+		return this;
 	}
 
-	public on(event: string, listener: EventListener): void {
+	public on(event: string, listener: EventListener): IEventEmitter {
 		if (!this._eventListeners.has(event)) {
 			this._eventListeners.set(event, []);
 		}
@@ -35,11 +38,12 @@ export class Eventified {
 	}
 
 	// Remove an event listener
-	public removeListener(event: string, listener: EventListener): void {
+	public removeListener(event: string, listener: EventListener): IEventEmitter {
 		this.off(event, listener);
+		return this;
 	}
 
-	public off(event: string, listener: EventListener): void {
+	public off(event: string, listener: EventListener): IEventEmitter {
 		const listeners = this._eventListeners.get(event) ?? [];
 		const index = listeners.indexOf(listener);
 		if (index > -1) {
@@ -49,10 +53,12 @@ export class Eventified {
 		if (listeners.length === 0) {
 			this._eventListeners.delete(event);
 		}
+
+		return this;
 	}
 
 	// Emit an event
-	public emit(event: string, ...arguments_: any[]): void {
+	public emit(event: string, ...arguments_: any[]): boolean {
 		const listeners = this._eventListeners.get(event);
 
 		if (listeners && listeners.length > 0) {
@@ -61,6 +67,8 @@ export class Eventified {
 				listener(...arguments_);
 			}
 		}
+
+		return true;
 	}
 
 	// Get all listeners for a specific event
@@ -69,12 +77,14 @@ export class Eventified {
 	}
 
 	// Remove all listeners for a specific event
-	public removeAllListeners(event?: string): void {
+	public removeAllListeners(event?: string): IEventEmitter {
 		if (event) {
 			this._eventListeners.delete(event);
 		} else {
 			this._eventListeners.clear();
 		}
+
+		return this;
 	}
 
 	// Set the maximum number of listeners for a single event