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Emmanuel C. Okolie
Emmanuel C. Okolie

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What You Should Know About JavaScript pop() function for beginners

Introduction

As a beginner, in the field of software development especially if you will be learning JavaScript. You will need to work with JavaScript arrays at some point. And working with arrays will make you want to add or remove something in the Array collection.

Note, In JavaScript, an array is a data structure that stores a collection of items. The items can be of any data type, such as numbers, strings, or objects. Arrays are declared using square brackets [] and items are separated by commas.
So if you want to be able to remove from the array lists what has been added, then this Tutorial is for you.

If you want to read some of my tutorials here’s where you can get them, or if you want to view some of my projects you can see them on my repository.

Now without taking your time let's head on to the tutorial!

What is the JavaScript pop() method

The javaScript pop() method is an in-built function that is used to remove the last element from an array and returns that element.
For instance, if you have an E-commerce application and you have listed the goods you want to sell in an array format, and you want to remove the last item you just added you can use the pop() method it will save you a lot of stress and make your work much cleaner.

If you call pop() of an empty array, it returns undefined.
The shift() function has a similar purpose to pop(), except that it works on the first element in an array.

What Is The pop() Used For

The pop() method is commonly used to remove the last element from an array and return it for further processing or storage. It is often used in situations where you want to keep track of the last item added to a list, or when you need to remove the last item from a list and return it for some other purpose, such as displaying it to the user or adding it to another list.

One common use case of the pop() method is in a stack data structure, where items are added and removed in a last-in, first-out (LIFO) order. The pop() method is used to remove the last item added to the stack.

Another common use case is when you want to remove the last element of an array and return it as a result of a function. For example, in a game where you have a list of players and you want to remove the last one from the list every time a new round starts.

It's also worth noting that the pop() method modifies the original array, so it's important to take that into account when using it in your code. If you want to keep a copy of the original array intact, you should make a copy of it before using the pop() method or use other methods such as slice() which don't modify the original array.

How To Make Use Of The JavaScript pop()

To remove the final element from an array and return it, use the pop() function in JavaScript. Here is an illustration of how to apply it:

let fruits = ["apple", "banana", "cherry"]; 
let lastFruit = fruits.pop(); 
console.log(fruits); //output: ["apple," "banana"] 
console.log(lastFruit); //Output: "cherry"
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In the above example, fruits.pop() transfers the final fruit a cherry from the array of fruits to the variable lastFruit. The eliminated element is also recorded in the console along with the changed fruits array.

Remember that the pop() function may be used to remove the final element and save it in a variable for later use. It alters the original array and returns the deleted element.

Few Things You Should know About the pop() method

This section is the intriguing part of this tutorial that brings awareness of the pop() method to you.

Below are a few things you should know about the pop() method in JavaScript:

  1. The pop() method modifies the original array. After calling pop(), the last element is removed from the array and the length of the array is shortened by 1.

  2. The pop() method returns the removed element. This means that you can store the removed element in a variable for later use.

  3. If the array is empty, the pop() method returns undefined.

  4. The pop() method can be called on any array-like object, not just true arrays.

  5. If you need to remove an element from a specific position in an array, you can use the splice() method instead of pop().

  6. The pop() method is an in-place operation, it does not create a new array, it modifies the original array.

  7. The pop() method mutates the original array. If you want to remove the last element from an array without mutating the original array, you can use the slice() method.

  8. The pop() method does not accept any parameter.

  9. The pop() method is supported in all modern browsers and can be used in both client-side and server-side JavaScript.

    Examples Of pop() Method In JavaScript

Here we will be looking at a few examples in which we used the pop() method and briefly explain how they work in each of the examples

Example-1
Let’s illustrate the pop() by creating a digit array, and using the pop() method on it.

// pop returns any type of object
var digit = [
  [1, 2, 3],
  [4, 5, 6],
  [-6, -7, -8],
];
console.log(digit.pop()); // [ -6, -7, -8 ]
console.log(digit); // [ [ 1, 2, 3 ], [ 4, 5, 6 ] ]
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Looking at the above examples you will find a few comments beside the codes those comments explain the essence of the code.

Example 2: Remove the last element from the JS Array
Let’s illustrate the actions of the pop method by creating a songList array and using the pop method on it.

let songList = ["my help", "Imolede", "praises", "last last", "unstoppable"];

let removedSongList = songList.pop();

console.log(songList, removedSongList);
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Above is a better example of how the pop method can be used, we used it to remove “unstoppable ” from the list, and after removing it from the list the remaining list will be published.

Example 3: Using pop() method in a function
Removing the last value from the array and using the document.write a function to display it on your screen and not your console.

// Illustration of pop() function in Javascript
function testing() {
var food = ["Rice", "Bread", "Beans", "Malt"];
// here we are popping last element from the array
var popped = food.pop();
document.write("Element That is removed from the array is : " + popped);
document.write("<br>");
document.write("Remaining elements are: " + food );
}
testing();
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The above example above is the last example I’ll be illustrating here, but they're more you can use the pop() method for.

Conclusion

Good one finally we’ve come to the end of this tutorial. Hopefully, you’ve gotten a ton of value from this tutorial What You Should Know About JavaScript pop() function for beginners.

We’ve seen alot by just talking about this tutorial. feel free to drop a comment! And please follow me for more tutorials.

Till next time, have a wonderful day!

About The Author

Emmanuel Okolie is a full-stack laravel developer with 2+ years of experience in the software development industry.

He has grown full-blown skills in combining Software Development, Writing, and Teaching others what he does. His stacks include JavaScript, PHP, ReactJs, Laravel, and more.

He is currently freelancing, building websites for clients, and writing technical tutorials teaching others how to do what he does.

Emmanuel Okolie is open and available to hear from you. Kindly visit and follow him on Linked-In, Facebook, Github, Twitter, or his Website.

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