(Array Methods Part 1) What are Mutator Methods?

When we started to learn javascript anytime we will meet the famous array methods. Array methods can be separated in three types:

• Mutator Methods
• Accessor Methods
• Iteration Methods

I will create one post for each array type methods, but today I will explain about the first type.

Mutator Methods

Mutator methods besides return a value, they also change original array, such as:

.sort() - sort method organize array in alphabetical order.

The return of this method is the array itself with the changes.

const animals = ['dog', 'cat', 'turtle', 'bird'];
animals.sort();
console.log(animals) // output: ['bird', 'cat', 'dog', 'turtle']

Some others examples:

.push() - push method insert elements into the end of an array

This method change the original array and return the new length, so we can classify as mutator method.

const animals = ['dog', 'cat', 'turtle'];
const count = animals.push('bird');
console.log(count); // output: 4
console.log(animals); // output: ['dog', 'cat', 'turtle', 'bird']

There are a lot of types of mutator methods and if I explain about all methods I think this post will be very big, but that's not my intention, so I will list some important mutator methods that I think you should be study:

• .unshift()
• .shift()
• .pop()
• .reverse()
• .splice()
• .fill()

See you soon!!!