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JavaScript Introducing ES2015 Objects and New Collection Types Map

What's the difference between set and add?

Hello, my question is in the title :) Thank you very much.

Ali Adams
Ali Adams
3,467 Points

The Add method adds a value to the end of the list. Set is used to replace an existing value in a specific index in the list. The usage of either depends on the program you're writing. So just be aware of what each one does and use it accordingly. Hope this helps.

2 Answers

set is the method you use to add a new key-value pair to a Map object.

add is the method you use to add a new unique value to a Set object.

Neither object has the other's method (Map doesn't have an add method, Set doesn't have a set method). It's just how they are named.

Couldn't agree more with Simmons Also, note that the add method in the Set prototype is what ensures the uniqueness of data