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iOS Swift 2.0 Functions Function Parameters Returning Complex Values

Artem Kazanovskiy
Artem Kazanovskiy
1,124 Points
Posted by Artem Kazanovskiy
Artem Kazanovskiy
1,124 Points

swift_lint.swift:13:12: error: cannot convert return expression of type '(Double, Double).Type' to return type '(Double,

Why my code cannot be compiled?

functions.swift 
// Enter your code below

func getTowerCoordinates(location: String) -> (Double, Double) {

    switch location {
        case "Eiffel Tower": (48.8582, 2.2945)
        case "Great Pyramid": (29.9792,31.1344)
        case "Sydney Opera House": (33.8587, 151.2140)
        default: (0,0)
    }
    return (Double, Double)
}


getTowerCoordinates("Great Pyramid")

2 Answers

Greg Kaleka
Greg Kaleka
39,021 Points
Greg Kaleka
Greg Kaleka
39,021 Points

Hi Artem,

You're trying to literally return (Double, Double), but what you should be doing is returning a tuple with two actual Double values. The other problem is that your switch statement isn't doing anything at all. Switch statements work like this:

switch.swift 
switch someVariable {
  case "This value": //do something
  case "Another value": //do something else
}

In your switch statement, you're missing the do something part, and instead are just "saying" a set of numbers. Instead, you should either directly return those numbers, or put them in a variable, and then after the switch statement, return that variable. We'll do it the first way.

solution.swift 
// Enter your code below

func getTowerCoordinates(location: String) -> (Double, Double) {

    switch location {
        case "Eiffel Tower": return (48.8582, 2.2945)
        case "Great Pyramid": return (29.9792,31.1344)
        case "Sydney Opera House": return (33.8587, 151.2140)
        default: return (0,0)
    }
}


getTowerCoordinates("Great Pyramid") // this will *return* (29.9792, 31.1344)

Make sense?

Cheers :beers:

-Greg

Passavudh Sabpisal
Passavudh Sabpisal
4,474 Points

Thank you! I got into the exact same confusion :)