Javascript - Arrow Function Expression


An arrow function expression has a shorter syntax than a function expression and does not bind its own:

  • this,
  • arguments,
  • super,
  • or

These function expressions are best suited for non-method functions.

As an arrow function does not:

  • bind its own this, it doesn't create then its own this context, this has its original meaning from the enclosing context (even in non strict).
  • bind an arguments object. Arguments are simply a reference to the same name in the enclosing scope.
  • bind to It cannot be used as constructors and will throw an error when used with new.



(param1 = defaultValue1, param2, …, paramN = defaultValueN) => { statements }
(param1 = defaultValue1, param2, …, paramN = defaultValueN) => expression  // equivalent to { return expression; }


The following syntax is also supported:


const myFunction = (param1: Type1, param2: Type2): ReturnType => {
  // function body


Circle Area

var area = (r) => Math.PI * r ** 2;
var rayon = 3;
console.log(`The area of a circle with the rayon ${rayon} is ${area(rayon)}`);

Destructuring Assignment

var f = ([a, b] = [1, 2], {x: c} = {x: a + b}) => a + b + c;


  • in [a, b] = [1, 2]:
    • a get the value 1
    • b get the value 2
  • in {x: c} = {x: a + b}
    • c get the value a + b thus 3
  • then a + b + c equal:
console.log(f());  // 6

Documentation / Reference

Discover More
CommonJs (NodeJs) - Require

The import functionality implementation of commonjs (and then node) is done via the require function require basically: reads a Javascript file (generally a CommonJs module but it may be any javascript...
ES - ES6 Harmony (ES2015)

ECMAScript 6 (also known as ES2015). The first ECMAScript Harmony specification, it is also known as ES6 Harmony class declarations (class Foo...
Imperative Vs Functional
Functional Programming - Map

A page the map functional programming function The map method creates a new collection with the results of calling a provided function on every element in the collection. The map operation produces...
Javascript Function Method
Javascript - Functions

Functions functionalities in Javascript. A function in Javascript is a variable that’s given a reference to the function being declared. The function itself is a value (as an integer or an array) that...
Javascript - Map function (Functional programming)

The functional programming function map in a Javascript context is only an array method as all functional programming javascript method. map With an Arrow function as argument Letters that we...
Chrome Dev Tool Source Debugger Scope
Javascript - This

this is a variable that has a reference value to the scope (namespace) this printThisobjthisobj Generally, this is the local scope but it may be changed. You can set this : in the call of a function...

Share this page:
Follow us:
Task Runner