Traditionally, the way variable declarations work has been one tricky part of programming in JavaScript. In most C-based languages, variables (more formally known as bindings, as a name is bound to a value inside a scope) are created at the spot where the declaration occurs. In JavaScript, however, this is not the case. Where your variables are actually created depends on how you declare them, and ECMAScript 6 offers options to make controlling scope easier. This chapter demonstrates why classic var declarations can be confusing, introduces block-level bindings in ECMAScript 6, and then offers some best practices for using them. ...

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