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iOS Functions in Swift Adding Power to Functions Returning Complex Values

Adrian Yao
Adrian Yao
1,002 Points
Posted by Adrian Yao
Adrian Yao
1,002 Points

I do not understand external and local names here?

I think thats the main problem? is there anything else wrong with the code?

functions.swift 
// Enter your code below

func coordinates(for location: Strings) -> (Lat: Double, Lon: Double) {
switch for {
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)
}
}

1 Answer

Heath Robertson
Heath Robertson
3,158 Points

Everything is correct, except you are switching on the external name. The correct way to do this is like so:

func coordinates(for 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)
    }
}

Because location is the local name, that is what you switch on. Maybe rewatch the corresponding videos to brush over this concept.

Anyway, I hope this helped :)

EDIT -- I just reread it: It is possible it doesn't matter whether you switch on the local or external name. The main problem is that the cases are not strings, and are just typed

 case "Eiffel Tower": return(48.8582, 2.2945)
        case "Great Pyramid": return(29.9792, 31.1344) // Correct
        case "Sydney Opera House": return(33.8587, 151.2140)

 case Eiffel Tower: return(48.8582, 2.2945)
        case Great Pyramid: return(29.9792, 31.1344) // Incorrect
        case Sydney Opera House: return(33.8587, 151.2140)
Adrian Yao
Adrian Yao
1,002 Points
Adrian Yao
Adrian Yao
1,002 Points

func coordinates(for location: Strings) -> (Lat: Double, Lon: 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) } }

It still says "Make sure you accept a single parameter of type String in your function declaration with the correct argument labels"? Help is appreciated. Thanks.

Heath Robertson
Heath Robertson
3,158 Points

Ohhh. I see!

You have typed 

func coordinates(for location: Strings)

instead of:

func coordinates(for location: String)

You made 'String' plural.