Go deeper into nested scope, a series of containers for variables and functionsĮxplore function- and block-based scope, 'hoisting', and the patterns and benefits of scope-based hidingĭiscover how to use closures for synchronous and asynchronous tasks, including the creation of JavaScript libraries Learn about scope, a set of rules to help JavaScript engines locate variables in your code Armed with this knowledge, you can achieve true JavaScript mastery.

Like other books in the You Don't Know JS series, Scope and Closures dives into trickier parts of the language that many JavaScript programmers simply avoid.

You'll learn how and why they work, and how an understanding of closures can be a powerful part of your development skillset. This concise yet in-depth guide takes you inside scope and closures, two core concepts you need to know to become a more efficient and effective JavaScript programmer. No matter how much experience you have with JavaScript, odds are you don't fully understand the language.

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