April 2018
Intermediate to advanced
284 pages
5h 46m
English
Content preview from Simplifying JavaScript
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| Tip 14 | Iterate Over Key-Value Data with Map and the Spread Operator |
In this tip, you’ll learn how to iterate directly over key-value data in maps with either loops or the spread operator.
In the previous tip, you saw how maps are an improved key-value collection when you’re regularly adding or deleting items. As you saw, objects are very useful, but there are times when a map has distinct advantages. You can see those advantages on the Mozilla Developer Network.[16]
You’ve already explored several advantages pertaining to when keys are set. Now you’re going to explore another suggested usage for maps: collections that are iterated.
Objects are very frustrating to iterate over. In fact, there used to be no way to directly iterate over them. You ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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