Binary operator '+' cannot be applied to two 'NSNumber' operands -- swift 3

Question

Help. I just converted to swift 3 and am getting errors when I try to add two NSNumbers together i.e.:

var foodPrice: NSNumber!
var priceSum: NSNumber!
foodPrice = 6.79
priceSum = 11.89
var totalSum = NSNumber(foodPrice + priceSum) // <-- error here

OR

var totalSum = (foodPrice + priceSum) as NSNumber // <-- still error here

Doesn't matter how I change totalSum I can't get away from this error. Please help. This is my official SOS. Dazed and confused here. How do I make this work?

There is no `+` operator which takes `NSNumber` operands. – Martin R Oct 04 '16 at 07:31 — Martin R, Oct 04 '16 at 07:31

score 1 · Answer 1 · answered Oct 04 '16 at 07:36

1

Why not write your own + override for NSNumber?

func + (lhs: NSNumber, rhs: NSNumber) -> NSNumber {
    return NSNumber(value: lhs.floatValue + rhs.floatValue)
}

var foodPrice: NSNumber = 6.79
var priceSum: NSNumber  = 11.89

var totalSum = foodPrice + priceSum // 18.68

I use floats here but you can use any type you need.

answered Oct 04 '16 at 07:36

JAL

41,701
23
172
300

1

The problem that I see is: What is *"any type you need"*? The application might use NSNumbers containing (for example) Float, Double, and (U)Int64 at different places. No matter which representation you use in your `+` operator, it won't work correctly in all cases. – Martin R Oct 04 '16 at 07:58
@MartinR Your right, this isn't really a reusable approach. Any suggestions how to improve this function (if any)? Or just treat each NSNumber on a case by case basis. – JAL Oct 04 '16 at 18:33

score 0 · Answer 2 · answered Oct 04 '16 at 07:31

0

var foodPrice: NSNumber!
var priceSum: NSNumber!
foodPrice = 6.79
priceSum = 11.89
var totalSum = NSNumber(double: foodPrice.doubleValue + priceSum.doubleValue)

Try this out..!

answered Oct 04 '16 at 07:31

user3608500

835
4
10

score 0 · Answer 3 · answered Oct 04 '16 at 07:32

0

Try

var totalSum = NSNumber(value: foodPrice.doubleValue + priceSum.doubleValue)

answered Oct 04 '16 at 07:32

Avt

16,927
4
52
72

Binary operator '+' cannot be applied to two 'NSNumber' operands -- swift 3

3 Answers3