The Unsung Heroes of Memory Management: WeakMap and WeakSet

Dive into the JavaScript collections that prevent memory leaks and streamline garbage collection

Photo by Possessed Photography on Unsplash

In the world of JavaScript, memory management is a critical aspect of building efficient and performant applications. While traditional collections like Object and Map can hold references to objects, they can also inadvertently cause memory leaks if those objects are no longer needed but are still kept in memory due to the strong references.

Enter WeakMap and WeakSet — two specialized collections that help mitigate this issue and ensure efficient garbage collection.

WeakMap: The Key-Value Store with a Twist

The WeakMap is a collection that holds key-value pairs, where the keys must be objects, and the values can be arbitrary values. The key difference between WeakMap and the regular Map is that WeakMap holds weak references to its keys.

This means that if an object used as a key in the WeakMap has no other strong references, the garbage collector can reclaim its memory, and the corresponding key-value pair is removed from the WeakMap.

Here’s an example of how you can use WeakMap:

const person1 = { name…