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Simplifying JavaScript
book

Simplifying JavaScript

by Joe Morgan
April 2018
Intermediate to advanced
284 pages
5h 46m
English
Pragmatic Bookshelf
Content preview from Simplifying JavaScript
Tip 16 Keep Unique Values with Set

In this tip, you’ll learn how to quickly pull unique items from an array with Set.

Set is a fairly simple collection that can do only one thing, but it does it very well. Set is like a specialized array that can contain only one instance of each unique item. You’ll often want to collect values from a large array of objects, but you only need to know the unique values. There are other use cases as well, but collecting a list of distinct information from a group of objects is very, very common.

In that spirit, return once again to our set of filters that you’re building. To even know what a user can filter on, you need to gather all the possible values. Recall the array of dogs that you worked with earlier. ...

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Publisher Resources

ISBN: 9781680506044Errata Page