Hoisting is a default behaviour in JavaScript where all the declarations (variables & functions) are moved to the top of the current scope. I’m gonna discuss on variable hoisting today.

Let’s understand the variable hoisting with the below sample.

a = "Hello";console.log(a); // Hello var a;

We can see “Hello” on the console even though we declared ‘a’ in the end. Well, This is where hoisting comes into play. By default, JavaScript moves the declarations at the top while execution, and it is initialized. This is ‘Variable Hoisting’

Let’s look into another example.

console.log(a); //undefinedvar a = "Hello";

We see “undefined” in the console. But Why ?

This is because by default JavaScript moves only the declaration at the top and not the ‘initialization’

Thanks for reading this story.

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Today we gonna discuss the flat() method in JavaScript which can be a part of the interview in the way to becoming a JavaScript developer.

The flat() method is used to flatten the array of arrays. The process of flattening depends on the depth of the array we want to flatten.

Syntax And Return Type 

flat(depth) :—  The depth level specifies how deep a nested array structure should be flattened. Default value is 1.
Return Type — A new array with sub-array elements concatenated into itExamples

let arr1 = [1,2,[3,4,[5,6,]]];

arr1.flat(1) // [1,2,3,4,[5,6]];

arr1.flat(2) // [1,2,3,4,5,6];

arr1.flat(0) // [1,2,[3,4,[5,6]]];

Hope this article may helpful to all !!

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