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!
There's no better feeling than being able to remove a library to complete a task that should be native to the language. This trick brings us one step closer to that!
![Write Better JavaScript with Promises]()
You've probably heard the talk around the water cooler about how promises are the future. All of the cool kids are using them, but you don't see what makes them so special. Can't you just use a callback? What's the big deal? In this article, we'll...
![Regular Expressions for the Rest of Us]()
Sooner or later you'll run across a regular expression. With their cryptic syntax, confusing documentation and massive learning curve, most developers settle for copying and pasting them from StackOverflow and hoping they work. But what if you could decode regular expressions and harness their power? In...
![MooTools FontChecker Plugin]()
There's a very interesting piece of code on Google Code called FontAvailable which does a jQuery-based JavaScript check on a string to check whether or not your system has a specific font based upon its output width. I've ported this functionality to MooTools.
The MooTools...
![Image Reflections with CSS]()
Image reflection is a great way to subtly spice up an image. The first method of creating these reflections was baking them right into the images themselves. Within the past few years, we've introduced JavaScript strategies and CANVAS alternatives to achieve image reflections without...
If you’re forced to stay in EC5-land without the spread operator, you can use the pollyfillable
Array.from()Doesn’t seem to work for arrays of objects unless I’m missing something.
If your array is an object, you can use map function, to get the value in an array.
then you can run method like above.
Anybody using babel with this one should be cautious, this will result in an array with a single set element. Patrick Denny’s is the most predictable form.
Thanks David! Very helpful! :)