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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 3 Isolate Information with Block Scoped Variables

In this tip, you’ll learn how let prevents scope conflict in for loops and other iterations.

At one point or another, every developer will make the mistake of capturing the wrong variable during a for loop. The traditional solution involves some pretty advanced JavaScript concepts. Fortunately, the let variable declaration makes this complex issue disappear.

Remember, when you use a block scoped variable declaration, you’re creating a variable that’s only accessible in the block. A variable declared in an if block isn’t available outside the curly braces. A variable declared inside a for loop isn’t available outside the curly braces of the for loop. But that doesn’t mean you can’t access ...

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Publisher Resources

ISBN: 9781680506044Errata Page