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iOS Object-Oriented Swift Classes in Swift Classes with Custom Types

Object Oriented Swift, Classes with Custom Types, solved, but why did it work?

I completed this challenge by hardcoding the values for location within the Business class, but when I was just trying to set the type without hardcoding, I was getting this error: error: cannot convert value of type 'Double.Type' to expected argument type 'Double' self.location = Location(latitude: Double, longitude: Double)

Why did this work: ` [...]

class Business { [...]

init(name: String, location: Location) {
    self.name = name
    self.location = Location(latitude: 1.00, longitude: 1.00)
}

} `

But not this:

` [...]

class Business { [...]

init(name: String, location: Location) {
    self.name = name
    self.location = Location(latitude: Double, longitude: Double)
}

} ` Shouldn't a good development technique be to be abstract as much as possible? Also, if I try to initialize an instance of Business, it winds up having the characteristics in the initializer, NOT the ones I'm trying to impose upon creation (i.e. lat and long will be 1.00, not any other Double I enter in).

Thank you!

1 Answer

Steven Parker
Steven Parker
231,184 Points

This is just a guess.

I'm not a Swift programmer, but based on other languages I know, I would expect that second line of the init method to be:

        self.location = location

And the specific values would be passed in when you create the instance, right?

And I'd guess that 2nd answer didn't work because it's a syntax error to redefine Location in that context, but the first one got by because it's syntactically valid and the checker didn't notice that the values were rigidly defined inside the method?

OH WOW. That was it. I was overthinking it. Thank you!!