Static & Private Class Fields

Why is it beneficial to make the listeners collection private?

class EventEmitter {
  #listeners = new Map();
  
  on(event, callback) {
    if (!this.#listeners.has(event)) {
      this.#listeners.set(event, new Set());
    }
    this.#listeners.get(event).add(callback);
  }
  
  emit(event, data) {
    this.#listeners.get(event)?.forEach(callback => callback(data));
  }
}

Improved event handling speed
Better memory management
Protected event handling integrity
Private listeners collection provides several benefits: 1) Prevents external modification of listener lists, 2) Ensures listeners can only be added through proper methods, 3) Protects event handling mechanism from tampering, 4) Maintains integrity of the event system, 5) Enables implementation changes without breaking code, 6) Prevents accidental listener manipulation.
Simplified event registration

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