JavaScript Closure Use Case - Avoid memory leaks and improve performance

The closure is a very important concept of JavaScript both in terms of performance improvement of your application and Interviews. All JavaScript developers have to learn this concept. With this blog, we can understand how we can avoid excess memory leaks using a closure. A memory leak is one of the major problems in JavaScript. JavaScript doesn't have memory management primitives, unlike c which has malloc, calloc for creating and freeing memory. In javaScript, garbage collection happened automatically. So here we need to be extra cautious to handle memory leaks.

Here is an example of how closure can be a life savior for a JavaScript developer

Before closure:

function multiplier(b){

  let a = Math.pow(5,5)

  return a * b

}|


multiplier (20) // 62500

multiplier (40) // 125000        

Here, whenever multiplier called let Val = Math.Pow(5,5) is created and preserves certain memory, for this particular case, large memory is used due to the large numeric value is generating here.

After Closure -

function multiplier(){

  let a = Math.pow(5,5)

  return function(b){

    return a * b

  }

}


let multiplicand = multiplier()

multiplicand(20) // 62500

multiplicand(40) // 125000        

With this example, the inner function creates a closure with variables defined in its lexical scope and they would be available outside too. So here, let value = Math.pow(5,5) is not created again and again which saves excessive memory leaks.

This approach also improves application performance.

#happylearning #javaScriptworld