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iOS

Posted by Nate Camorlinga
Nate Camorlinga
1,165 Points

Why won't this very simple class in swift work?

This is part of the code challenge in the ios beginner course. I don't understand why this wouldn't work. Can someone explain? Thanks!

class Shape {

var numberOfSides: Int

init() {
    let someShape = Shape(numberOfSides: 2)
    print(numberOfSides)
}

}

1 Answer

andren
andren
28,558 Points
andren
andren
28,558 Points

There are a couple of issues:

  1. You have not added numberOfSides as a parameter to init, and have not initialized the numberOfSides property.

  2. You try to create an instance of the class within the class' init method, which is invalid because it would lead to an infinite loop of the object creating instance of itself over and over.

Here is the corrected code with some comments added:

class Shape {
  var numberOfSides: Int

  init(numberOfSides: Int) { // Add numberOfSides as parameter
    self.numberOfSides = numberOfSides // Initalize the numberOfSides property by assigning it the property that is passed in
  }
}

let someShape = Shape(numberOfSides: 2) // Create instance of the class outside of the class' definition

If you have any further questions then feel free to ask, I'll try to clarify anything you might be confused about.