Example of a Module Design Pattern in JavaScript

shoppingCart.js

/*MODULE PATTERN*/

//create a namespace
var shoppingCart = (function() {

    //private variables
    var total;
    var basket = [];

    //private methods
    function viewCart() {
        basket.forEach(function(el) {
            console.log(el.item + '\t\t$' + el.price);
        })
    };

    //public variables and methods
    return {
        //public alias to private function
        getCart: viewCart,

        addItem: function(values) {
            basket.push(values);
            return this;
        },

        removeItem: function(name) {
            basket.forEach(function(product, index) {
                if (name === product.item) {
                    basket.splice(index, 1);
                }
            });
            return this;
        },

        getItemCount: function() {
            return basket.length;
        },

        getTotal: function() {
            total = 0;
            basket.forEach(function(item) {
                total += item.price;
            })
            return total;
        }

    }

}());

shoppingCart.addItem({
    item: 'Bobby Socks',
    price: 1.99
}).addItem({
    item: 'Pink T-shirt',
    price: 10.99
}).addItem({
    item: 'AquaFresh',
    price: 43.98
}).addItem({
    item: 'Visine Ultra',
    price: 4.99
}).addItem({
    item: 'Bobby Socks',
    price: 1.99
});

shoppingCart.getCart();
/*
Bobby Socks     $1.99
Pink T-shirt    $10.99
AquaFresh       $43.98
Visine Ultra    $4.99
Bobby Socks     $1.99
*/
console.log((shoppingCart.getTotal()).toFixed(2)); //63.94
shoppingCart.removeItem('Visine Ultra'); //63.94
console.log((shoppingCart.getTotal()).toFixed(2)); //58.95
console.log(shoppingCart.removeItem('Bobby Socks').getTotal()); //54.97
console.log(shoppingCart.getItemCount()); // 2

shoppingCart.getCart();
/*
Pink T-shirt    $10.99
AquaFresh       $43.98
*/

console.log((shoppingCart.getTotal()).toFixed(2)); //54.97

shoppingCart.addItem({
    item: 'Samsung Galaxy',
    price: 499.99
}).addItem({
    item: 'Apple Ipad',
    price: 750.99
}).addItem({
    item: 'Eloquent JS',
    price: 24.98
}).addItem({
    item: 'Trojan Condoms',
    price: 8.99
}).addItem({
    item: 'Tube Sock',
    price: 1.99
});

shoppingCart.getCart();

/*
Pink T-shirt    $10.99
AquaFresh       $43.98
Samsung Galaxy  $499.99
Apple Ipad      $750.99
Eloquent JS     $24.98
Trojan Condoms  $8.99
Tube Sock       $1.99
*/

console.log((shoppingCart.getTotal()).toFixed(2)); //1341.91
shoppingCart.removeItem('Samsung Galaxy');
shoppingCart.getCart();
/*
Pink T-shirt    $10.99
AquaFresh       $43.98
Apple Ipad      $750.99
Eloquent JS     $24.98
Trojan Condoms  $8.99
Tube Sock       $1.99
*/