Javascript Closures

The previous line is hard to understand because its about closures which is a very critical concept in Javascript.In this blog we will take a look at Javascript closures and will try to make it simplke for you all.

JavaScript allows writing function inside an outer function. We can write as many inner functions as we want. If inner function access the variables of outer function then it is called closure.

function outerFunction() {

    let count = 0;

    function innerFunction() {

        count++

        return count

    }

    return innerFunction

}

const innerFunc = outerFunction()

console.log(innerFunc())

console.log(innerFunc())

console.log(innerFunc())

//1

//2

//3

Let us more example of inner functions

function outerFunction() {

    let count = 0;

    function plusOne() {

        count++

        return count

    }

    function minusOne() {

        count--

        return count

    }

    return {

        plusOne:plusOne(),

        minusOne:minusOne()

    }

}

const innerFuncs = outerFunction()

console.log(innerFuncs.plusOne)

console.log(innerFuncs.minusOne)

Closures make JavaScript very powerful and versatile. Closure helps in data encapsulation, remove redundant code, etc.

In other languages this won't work but in JavaScript it works.