JavaScript ES6 Arrow functions

A little dive into => syntactic sugar.

Before :

> hello = function() { return "Hello World !" }

function() { return "Hello World !" }

> hello()

Hello World !

Now :

> hello = () => { return "Hello World !" }

() => { return "Hello World !" }

> hello()

Hello World !

> hello = () => "Hello World !"

() => "Hello World !"

> hello()

Hello World !

> [1,2,3].map( function(n) { return n*n } );

[ 1, 4, 9 ]

> [1,2,3].map( n => n*n );

[ 1, 4, 9 ]