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iOS Functions in Swift Adding Power to Functions Returning Complex Values

Posted by Alexander Tucker
Alexander Tucker
Courses Plus Student 1,262 Points

returning a tuple

//In this challenge, we have the following geographical coordinates

Eiffel Tower - lat: 48.8582, lon: 2.2945 Great Pyramid - lat: 29.9792, lon: 31.1344 Sydney Opera House - lat: 33.8587, lon: 151.2140

Declare a function named coordinates that takes a single parameter of type String, with an external name for, a local name of location, and returns a tuple containing two Double values (Note: You do not have to name the return values). For example, if I use your function and pass in the string "Eiffel Tower" as an argument, I should get (48.8582, 2.2945) as the value. If a string is passed in that doesn’t match the set above, return (0,0)// im having trouble it just keeps saying it need to return a tuple

functions.swift 
func coordinates(for location: String) -> (lat: Double, lon: Double) {
  switch location {
    case "Eiffel Tower" : (lat: 48.8582, lon: 2.2945)
    case "Great Pyramid" : (lat: 29.9792, lon: 31.1344)
    case "Sydney Opera House" : (lat: 33.8587, lon: 151.2140)
    defult : (lat: 0, lon: 0)
    }
    return(location)
}

1 Answer

Matthew Long
Matthew Long
28,407 Points
Matthew Long
Matthew Long
28,407 Points

There's a couple issues. First thing I noticed is you spell "default" without the "a". This will give you an error saying your switch statement is not exhaustive. Next, the challenge wants you to return an unnamed tuple. You return a tuple with lat and lon names: (lat: Double, lon: Double) instead of (Double, Double). Lastly, I used the return after every match:

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)
  }
}

There are other ways you can solve this as well. However, this is what makes the most sense to me.