Examples of Arrow Functions in JS

Arrow functions offer concise and efficient syntax for writing functions, making code cleaner and more readable while avoiding issues with 'this' binding.

Basic Arrow Function

const sayHello = () => {
  console.log("Hello!");
};

sayHello();

Arrow Function With a Single Parameter

const numbers = [1, 2, 3, 4, 5];
const doubledNumbers = numbers.map(num => num * 2);

console.log(doubledNumbers); // [2, 4, 6, 8, 10]

Arrow Function With Multiple Parameters

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

console.log(add(3, 4)); // Output: 7

Arrow function for Mapping an Array

const numbers = [1, 2, 3, 4, 5];
const doubledNumbers = numbers.map(num => num * 2);

console.log(doubledNumbers); // [2, 4, 6, 8, 10]

Arrow Function for Filtering an Array

const numbers = [1, 2, 3, 4, 5];
const evenNumbers = numbers.filter(num => num % 2 === 0);

console.log(evenNumbers); // Output: [2, 4]

Arrow Function With an Implicit Return

const double = num => num * 2;

console.log(double(6)); // Output: 12

Arrow Function as a Callback

const names = ["Alice", "Bob", "Charlie"];
const nameLengths = names.map(name => name.length);

console.log(nameLengths); // Output: [5, 3, 7]

Arrow Function With a Default Parameter

const greet = (name = "Anonymous") => {
  console.log(`Hello, ${name}!`);
};

greet(); // Output: Hello, Anonymous!
greet("John"); // Output: Hello, John!

Arrow Function With Destructuring Parameters

const getFullName = ({ firstName, lastName }) => `${firstName} ${lastName}`;

console.log(getFullName({ firstName: "John", lastName: "Doe" })); // Output: John Doe

Arrow Function Using The Rest Parameter

const sum = (...numbers) => numbers.reduce((acc, curr) => acc + curr);

console.log(sum(1, 2, 3, 4, 5)); // Output: 15

Arrow Function With a Ternary Operator

const isEven = num => num % 2 === 0 ? "Even" : "Odd";

console.log(isEven(6)); // Output: Even
console.log(isEven(7)); // Output: Odd

Arrow Function Used in setTimeout

setTimeout(() => {
  console.log("Delayed message");
}, 1000);

Arrow Function With a Conditional Statement

const getDiscountedPrice = (price, isPremiumMember) => {
  if (isPremiumMember) {
    return price * 0.8;
  } else {
    return price;
  }
};

console.log(getDiscountedPrice(100, true)); // Output: 80
console.log(getDiscountedPrice(100, false)); // Output: 100