g-akshay

var global = 10,            // some number
    anotherGlobal = 100,    // some number
    someObject;             // just declared
 
function anotherGlobal(){
    console.log('I am a function.');
}
 
function someObject(){
    global = 15;

g-akshay

var someobject = function(){
  . . .
};

g-akshay

function payBill(){
 
    // valid promo codes for current month to get discount on total payable amount
    var validCodes = ['FIRST50', 'OFF10', 'APP15', 'WALLET'];
 
    function checkCode(promoCode){
 
        if( validCodes.indexOf(promoCode) !== -1 )
        {
            console.log('Hurray!! You got a discount.')

g-akshay

function closureLoopBug() { 
    var i;
  
    for (i = 0; i < 5; i++) {    
        setTimeout(function() {
            console.log('Value of i: ' + i);
        }, 1000);
    } 
}
 

g-akshay

function myTimeout(i){
    setTimeout(function() {            
            console.log('Value of i: ' + i);
        }, 1000);
}
 
function closureLoopBug() { 
    var i;
  
    for (i = 0; i < 5; i++) {    

g-akshay

'use strict';
function closureLoopBug() { 
    
    for (let i = 0; i < 5; i++) {    
        setTimeout(function() {
            console.log('Value of i: ' + i);
        }, 1000);
    } 
}
 

g-akshay

function Person(name) {
    this.name = name;
}
Person.prototype.getName = function() {
    return this.name + '-parent';
}

function Author(name, books) {
    Author.superclass.constructor.call(this, name);
    this.books = books;

g-akshay

var contactName = '',
    message = 'this is spamming 😂😂',
    counter = 1,
    frequency = 10;

var count    = 0,
    interval = setInterval(function(){

        //selectContact(contactName);    

g-akshay

function Person( name, age, weight ) {
 
  this.name = name;
  this.age = age;
  this.weight = weight;
 
}


// a single instance of toString method will be shared amongst all the person objects

g-akshay

• Defined as a way to provide both private and public encapsulation for classes
• functions/properties are encapsulated using closures
• Start private attribute names with underscore (convention)

Pros

• Reduces chance of function name conflict with other devs
• You can return specific function based on some configuration or environment
• Revealing pattern makes it more clear at the end of module about the properties which are made public.