Unique Array Values
When you look at any programming language, you see missing features that you find puzzling because the use case seems so common. One such case is retrieving unique values from an array with JavaScript. Years ago I mentioned an easy way of unique value management using objects instead of arrays, but that's not always an option and doesn't match every use case.
Want to retrieve a unique array of values from an array that may include duplicate values? You can use new JavaScript spread operator with Set to get an array of unique values:
var j = [...new Set([1, 2, 3, 3])]
>> [1, 2, 3]
Getting unique array values is another awesome usage of the spread operator. And don't forget you can merge object properties with the spread operator!
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Thanks David! Very helpful! :)