Create Simple Class with multiple calculating function( ) - swift

Question

Trying to run a simple calculation via a function in my class. I simply want to add bill1 + bill2 and print the total amount spent on bills. So (bill1 + bill2 = total). And then print the total amount.
Current error states - "Code after 'return' will never be executed." Now, is my location for my print in the wrong location or did I declare my variables incorrectly? Should I be using vars instead of lets?
What do you recommend for my function in order to calculate and print the result?
class BillsCalculator
{
let nameOfBill1: String = "Medical"
let nameOfBill1: String = "Hulu"
let monthlyBillAmount1: Double = 34.25
let monthlyBillAmount2: Double = 7.99
let calculateTotalsPerMonth: Double = 0.0
//calculateTotalPerMonth ( = monthlyBillAmount_1 + monthlyBillAmount_2 + 3)
func calculateTotalsPerMonth(monthlyBillAmount: Double, monthlyBillAmount2: Double) -> Double
{
//totalBillsPerMonth = add(monthlyBillAmount1 + monthlyBillAmount2)
return totalBillsPerMonth(monthlyBillAmount1 + monthlyBillAmount2)
*Error println("You spend \(totalBillsPerMonth)")
}
}

Answer 1

First: "Code after 'return' will never be executed."
Yes it will not, after you call return you exit the function and return to the function that call it, you probably have an warning in XCode warning you about telling you that
Second: "Should I be using vars instead of lets"
If the value changes you MUST use var, if it does not you SHOULD use let.
Some problems I can see in your code:
class BillsCalculator
{
//use _ in the beginning of the name for class variables
//eg. _nameOfBill instead nameOfBill1
//It is not wrong use nameOfBill1 is just not recommended
//if nameOfBill1 change use var
let nameOfBill1: String = "Medical"
//Why is this declare twice
let nameOfBill1: String = "Hulu"
//Those values look like change should be var
var monthlyBillAmount1: Double = 34.25
var monthlyBillAmount2: Double = 7.99
var calculateTotalsPerMonth: Double = 0.0
func calculateTotalsPerMonth(monthlyBillAmount: Double, monthlyBillAmount2: Double) -> Double
{
totalBillsPerMonth = add(monthlyBillAmount1 + monthlyBillAmount2)
//print before return
println("You spend \(totalBillsPerMonth)")
return totalBillsPerMonth(monthlyBillAmount1 + monthlyBillAmount2)
}
}

Answer 2

Here you should either print the value of your total bill or return that value. As you just want to print the total bill amount so I would recommend you to just print, not to return anything. You can refer the below code.
class BillsCalculator
{
let nameOfBill1: String = "Medical"
let nameOfBill1: String = "Hulu"
let monthlyBillAmount1: Double = 34.25
let monthlyBillAmount2: Double = 7.99
let calculateTotalsPerMonth: Double = 0.0
//calculateTotalPerMonth ( = monthlyBillAmount_1 + monthlyBillAmount_2 + 3)
func calculateTotalsPerMonth(monthlyBillAmount: Double, monthlyBillAmount2: Double) -> Double
{
calculateTotalsPerMonth= add(monthlyBillAmount1 + monthlyBillAmount2)
println("You spend : "+totalBillsPerMonth);
}
}

Answer 3

One tiny error in your code
let nameOfBill1: String = "Medical"
let nameOfBill1: String = "Hulu"
These two variables have the same name, perhaps one should be:
let nameOfBill2: String = "Hulu"
And yes return is always the last line in the function, so any codes after return will never be executed. If you only want to get the total of two bills, you can simply do this:
func calculateTotalsPerMonth(monthlyBillAmount: Double, monthlyBillAmount2: Double) -> Double {
//println("You spend \(totalBillsPerMonth)")
return monthlyBillAmount1 + monthlyBillAmount2
}
and call this function with your bill variables, like:
let bill1 = 34.25
let bill2 = 7.99
let totalBill = calculateTotalsPerMonth(bill1, bill2)
println("You spent \(totalBill)")
Swift is a very smart language, and it is type safe. You can remove the type if you want, more like a personal programming style thing.
let bill1: Double = 34.25
let bill1 = 34.25
They both will be type "Double"

Answer 4

As others have said, you need to put your println statement before return since returns ends the execution of the method; thus println will never be run.
However, I would suggest a few changes to your current approach:
// A bill is an object - why not encapsulate it in a struct.
struct Bill {
let name: String
let amount: Double
}
// Using structs is generally preferred, unless you need inheritance and/or
// references to your BillsCalculator objects.
struct BillsCalculator {
let bill1: Bill
let bill2: Bill
// Using a read-only computed property means you don't need to set
// the total to have an initial value of zero.
var totalBilled: Double {
return bill1.amount + bill2.amount
}
}
// Since you're probably going to want to reuse BillsCalculator,
// don't have each bill set already. Instead, use BillsCalculator's
// initialiser and pass in bills.
let bill1 = Bill(name: "Medical", amount: 34.25)
let bill2 = Bill(name: "Hulu", amount: 7.99)
let cal = BillsCalculator(bill1: bill1, bill2: bill2)
print("You've spend \(cal.totalBilled) this month")