What Are JavaScript Sets and Maps?

In a vast variety of useful tools and features that JavaScript offers, powerful structures such as Sets and Maps often get overlooked.

What are they?

A Set is like a special list that is perfect when you need to ensure all your items are different.

On the other hand, a Map works a bit like a dictionary. Instead of words, you have keys, and instead of meanings, you have values.

A Set can be used to store names of people at a party without repetition, while a Map allows you to store people’s names and their favorite colors in a key-value pair.

Both Sets and Maps share some methods that make them easy to work with, such as set() to set a new value, get() to retrieve that value, and size to know the size of the structure.

However, when it comes to checking if something is a Set or a Map, it gets a little tricky, as using typeof returns both as objects. Instead, using instanceof will correctly tell you if your data is a Set or a Map.

Sets and Maps are powerful tools in JavaScript, allowing you to store and organize data in smart and efficient ways depending on your needs, and should be used more often.

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