JavaScript(JS) Set

In JavaScript, a Set is a built-in data structure that allows you to store unique values of any type. It is similar to an array, but with a few key differences.

One of the main differences between a Set and an array is that a Set can only contain unique values. If you try to add a value that already exists in the Set, it will be ignored. Additionally, a Set does not maintain the order of its values, whereas arrays are ordered.

Here are some examples of using a Set in JavaScript:

1. Creating a Set:

let mySet = new Set();

This creates a new empty Set instance.

2. Adding and retrieving values from a Set:

let mySet = new Set();

mySet.add("value1");
mySet.add("value2");

console.log(mySet.has("value1")); // output: true
console.log(mySet.has("value3")); // output: false

In this example, we add two values to the Set using the add() method, and then check if the Set contains a value using the has() method.

3. Iterating over a Set:

let mySet = new Set();

mySet.add("value1");
mySet.add("value2");

for (let value of mySet) {
  console.log(value);
}

In this example, we use a for...of loop to iterate over the values in the Set and log each value to the console.

4. Removing values from a Set:

let mySet = new Set();

mySet.add("value1");
mySet.add("value2");

mySet.delete("value1");

console.log(mySet.has("value1")); // output: false

In this example, we remove a value from the Set using the delete() method, and then check if the Set contains the value using the has() method.