Can you help me please , with bleep bleep


#1

Can you help me please , with bleep bleep ? I actually pass the excercise , however bill gives me the wrong bill.

var cashRegister = {
total:0,
//Dont forget to add your property
add: function(itemCost) {
this.total += itemCost;
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;
},
//Add the voidLastTransaction Method here
voidLastTransaction : function () {
this.total-=this.lastTransactionAmount ;

}

};

cashRegister.scan('eggs',1);
cashRegister.scan('milk',1);
cashRegister.scan('magazine',1);
cashRegister.scan('chocolate',4);

//Void the last transaction and then add 3 instead
cashRegister.voidLastTransaction();
cashRegister.scan('chocolate',3);

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


29. So meta I can't take it
#2

Disclaimer, I haven't done this project yet, but I get the right total. I get $8.55, what do you see?


#3

Hi in that method

total:0,
//Dont forget to add your property
add: function(itemCost) {
    this.total += itemCost;
    this.lastTransactionAmount = itemCost;
},

you first declare total and set it to 0 so you should do the same for lastTransactionAmount


Bleep Bleep: Variable is to Global Variable as This.Key is to...?
#5

@msfrisby Thank you , but actually i dont need to . And last question @wizmarco why

voidLastTransaction : function () {
this.total-=this.lastTransactionAmount ;
}

why it only refers to the last item , not all?


#6

@microwhiz78645
Yeap :slight_smile: I realized I was thinking of something else, that's why I deleted my post so quick :joy:

And to your question I believe it's because you assign the value of the most recent itemCost to lastTransactionAmount in your first method:

	add: function(itemCost) {
		this.total += itemCost;
		this.lastTransactionAmount = itemCost;    // here
	}