Confusion due to Swift lacking implicit conversion of CGFloat

Question

Trying to do arithmetic in a function that returns `CGFloat, I get an error:

Couldn\'t find overload for \'/\' that accepts supplied arguments

Answer 1

Its best to abstract away the complexity. First create an extension

extension Double {
    /** Converts the specified value in degrees into radians. */
    func degrees() -> CGFloat {
        return CGFloat(self) * CGFloat(M_PI / 180.0)
    }
}

then use it in your code such as the following example

let angle = 30.0.degrees()
let transform = CGAffineTransformRotate(self.sliderControl.transform, angle);

At first I was reluctant to extend Double because I don't like creating a custom tailored use of the language (from coding horrors found in C++). However, practical experience has shown this to being a way of abstraction natural to the language.