Crafting an EventEmitter
Understanding the Requirements
When we first receive the prompt, it's clear that we needed to create a custom event-handling system. The system should allow users to:
- Subscribe to an event with a callback function.
- Unsubscribe from an event to stop receiving notifications.
- Emit an event to notify all current subscribers.
Given these requirements, we begin thinking about the essential components needed to build this system.
Exploring Examples
Before diving into the code, let's start by exploring some examples to clarify our understanding. Imagine a scenario where multiple components (like buttons or data fetchers) would want to subscribe to an event called 'click'. Each would have its own callback function to execute when a 'click' event occurs.
This exploration leads us to consider a few key questions:
- How do we keep track of multiple subscribers for multiple events?
How do we efficiently notify all subscribers when an event is emitted?