arrow function in JavaScript

Harish Sahoo

7y1.3kWeb Development

what is arrow function in JavaScript?

4 Replies

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Bidyasagar Mishra7y ago
Accepted answer
Arrow functions allows a short syntax for writing function expressions.

You don't need the function keyword, the return keyword, and the curly brackets.

Arrow functions do not have their own this. They are not well suited for defining object methods.

Arrow functions are not hoisted. They must be defined before they are used.

Using const is safer than using var, because a function expression is always constant value.

You can only omit the return keyword and the curly brackets if the function is a single statement. Because of this, it might be a good habit to always keep them:

Example:
JavaScript Arrow Functions

Arrow functions are not supported in IE11 or earlier.

"demo">
Output: 25
+4
Ankit Kanojia5y ago
Arrow functions were introduced in ES6.

Before Arrow function
hello = function() {
  return "Hello World!";
}
After Arrow function
hello = () => {
  return "Hello World!";
}
Why choose Arrow function?
- arrow functions are less verbose than traditional functions.
- The syntax allows an implicit return when there is a no-body block, resulting in shorter and simpler code in some cases.
- arrow functions take this from their surroundings (lexical binding)
- Many more javascript libraries used this ES6 syntax as a function.
+2
Rajanikant Hawaldar7y ago
With esay understanding expalaination with examples
http://tc39wiki.calculist.org/es6/arrow-functions/
+5
Chittaranjan Swain7y ago
Hi Harish,

Pl Refer below links for more details,

Arrow functions were introduced in ES6.

An arrow function expression is a syntactically compact alternative to a regular function expression, although without its own bindings to the this, arguments, super, or new.target keywords. Arrow function expressions are ill suited as methods, and they cannot be used as constructors.

Ex-
var materials = [
'Hydrogen',
'Helium',
'Lithium',
'Beryllium'
];

console.log(materials.map(material => material.length));
// expected output: Array [8, 6, 7, 9]

https://www.sitepoint.com/es6-arrow-functions-new-fat-concise-syntax-javascript/
https://www.geeksforgeeks.org/arrow-functions-in-javascript/
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions
+4

arrow function in JavaScript

JavaScript Arrow Functions

Why choose Arrow function?