You Deserved It!


No error message. Could someone explain the following below lines of code to me?
(1) += (itemCost || 0); --- What purpose does the '||' serve?
(2) the parameter 'employee' is not introduced anywhere until the 'applyStaffDiscount' method. How does the code know to apply the StaffMember to the 'employee' parameter?
(3) console.log('Your bill is '; --- What purpose does the '.toFixed(2)' serve?

Thank you!

Replace this line with your code. 
function StaffMember(name,discountPercent){ = name;
    this.discountPercent = discountPercent;

var sally = new StaffMember("Sally",5);
var bob = new StaffMember("Bob",10);

// Create yourself again as 'me' with a staff discount of 20%
var me = new StaffMember ("me", 20);

var cashRegister = {
    lastTransactionAmount: 0,
    add: function(itemCost){ += (itemCost || 0);
        this.lastTransactionAmount = itemCost;
    scan: function(item,quantity){
        switch (item){
        case "eggs": this.add(0.98 * quantity); break;
        case "milk": this.add(1.23 * quantity); break;
        case "magazine": this.add(4.99 * quantity); break;
        case "chocolate": this.add(0.45 * quantity); break;
        return true;
    voidLastTransaction : function(){ -= this.lastTransactionAmount;
        this.lastTransactionAmount = 0;
    // Create a new method applyStaffDiscount here
    applyStaffDiscount: function (employee) { -=*(employee.discountPercent/100);

// Apply your staff discount by passing the 'me' object 
// to applyStaffDiscount

// Show the total bill
console.log('Your bill is ';


If itemCost is not a valid number, this expression returns 0 so that the total is not changed and no NaN results.


employee is only a local parameter, determined by the argument in the call to the method.


me in this case is defined as a StaffMember instance. That becomes the employee in the method.


This number method reduces the number decimal places in the result, based on the 5/4 rounding rule. Technically, if the amounts in the instructions are followed, it is not needed. When the values are altered, it does come into play.


This topic was automatically closed 7 days after the last reply. New replies are no longer allowed.