Arrow functions are a modern, concise way to write functions in JavaScript. Instead of using the traditional 

 syntax. They often make your code shorter and easier to read.

For example, consider a simple function that adds two numbers:

The parameters are listed in parentheses, followed by an arrow 

If the function consists of a single expression, that expression is automatically returned.

Create an arrow function named add that takes two parameters and returns their sum.

Call add with the numbers 3 and 4 and print the result using console.log.

index.js

index.test.js

Use an Arrow Function for Addition

Given the following traditional function, rewrite it as an arrow function:

Assign the arrow function to a constant named square.

Call square with the value 5 and print the result using console.log.

Convert a Named Function to an Arrow Function

## What Are Arrow Functions?

Arrow functions are a modern, concise way to write functions in JavaScript. Instead of using the traditional **function** keyword, arrow functions use the** =>** syntax. They often make your code shorter and easier to read.

For example, consider a simple function that adds two numbers:

### Traditional function syntax

```javascript
function add(a, b) {
  return a + b;
}
```

### Arrow function syntax

```javascript
const add = (a, b) => a + b;
```

In the arrow function version:

- We use **const** to declare **add** (since its definition won’t change).
- The parameters are listed in parentheses, followed by an arrow **=>**.
- If the function consists of a single expression, that expression is automatically returned.

---

## Exercises

@exercise 4355a6a6ffb8

@exercise 4694fc860c4a


- Luo nuolitoiminto nimeltä add, joka ottaa kaksi parametria ja palauttaa niiden summan.
- Kutsu **add** funktiota parametreilla 3 ja 4 ja tulosta paluuarvo käyttäen** console.log**-metodia.

Käytä nuolifunktiota yhteenlaskuun

Tässä on perinteinen funktio, kirjoita se uudelleen nuolifunktioksi:

```javascript
function square(n) {
  return n * n;
}
```

- Määritä nuolifunktio vakioon nimeltä **square**.
- Kutsu funktiota arvolla 5 ja tulosta paluuarvo käyttäen **console.log**.

Muuta nimetty funktio nuolifunktioksi

Arrow Functions in JavaScript

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Arrow Functions in JavaScript

What Are Arrow Functions?

Traditional function syntax

Arrow function syntax

Learn to hack — start here