Lesson 25 +15 XP

Arrow Functions

Arrow functions are a shorter way to write functions, added in ES6.

The syntax


js
const add = (a, b) => {
  return a + b;
};

Shorter forms

When there is only one expression, you can skip the braces and return:


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

With one parameter, you can skip the parentheses:


js
const double = x => x * 2;

Arrow vs regular

Regular function:


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

Arrow function:


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

Same result, less typing.

Important differences

  • Arrow functions do not have their own this.
  • They cannot be used as constructors with new.
  • They have no arguments object.

TL;DR

  • Arrow functions are a compact syntax: (a, b) => a + b.
  • Single expressions skip braces and return.
  • They have no own this, arguments, or new.