Hoisting in JavaScript

What is Hoisting in JavaScript?

The dictionary meaning of hoisting is – raise (something) by means of ropes and pulleys.

That is what JavaScript means by hoisting. It pulls all the variable and function declarations on top of your code. Well, not literally. It moves the declarations to top during code compilation so the decelerations are available before initialising the variable or invoking function.

Let’s try to understand this with some examples:

Using variable before declaring

Invoking function before defining

Though, We should keep in mind that hoisting pulls only the declarations to top and not initialisations. So, the below example will always log `undefined`.

Best Practices

Though you get hoisting for free but the best practice says that we should always declare our variables and define our functions before using them and invoking them respectively in order to save ourselves some mess. Also, declarations first approach will make life easier during debugging.


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