nested arrow functions code example

Example 1: Arrow Functions

// The usual way of writing function
const magic = function() {
  return new Date();
};

// Arrow function syntax is used to rewrite the function
const magic = () => {
  return new Date();
};
//or
const magic = () => new Date();

Example 2: pass a variable by reference to arrow function

// Parenthesize the body of a function to return an object literal expression:
params => ({foo: bar})

// Rest parameters and default parameters are supported
(param1, param2, ...rest) => { statements }
(param1 = defaultValue1, param2, …, paramN = defaultValueN) => { 
statements }

// Destructuring within the parameter list is also supported
var f = ([a, b] = [1, 2], {x: c} = {x: a + b}) => a + b + c;
f(); // 6

Example 3: concise body arrow functions javascript

const plantNeedsWater = day => day === 'Wednesday' ? true : false;

//If only 1 Parameter no () needed
//Single line return is implicit
//Single line no {} needed

Example 4: es6 arrow function

// ES6
const prices = smartPhones.map(smartPhone => smartPhone.price);
console.log(prices); // [649, 576, 489]