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iOS Object-Oriented Swift Value vs Reference Types Final Exam - Assignment

Scott Odle
Scott Odle
1,479 Points
Posted by Scott Odle
Scott Odle
1,479 Points

Why accept a "sides" parameter for the square at all? Squares always have 4 sides.

Doesn't make much sense.

Mahdi Pedramrazi
Mahdi Pedramrazi
2,505 Points
Mahdi Pedramrazi
Mahdi Pedramrazi
2,505 Points

I think logically the initializer for the Square class needs to accept only sideLength as a parameter. Since all Square shape object shave the same name and sides.

    init(sideLength: Double){
        self.sideLength = sideLength
        super.init(sides: 4, name: "Square")
    }

4 Answers

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

Yep - true! But that shouldn't get in the way of getting the assignment challenge complete though, eh?! ;-)

Steve.

Chris Nash
Chris Nash
Courses Plus Student 1,402 Points

haha

Jared Watkins
Jared Watkins
10,756 Points
Jared Watkins
Jared Watkins
10,756 Points

A square will always have 4 sides, but other shapes will have other numbers of sides. So, the property 'sides' should be declared in the base class 'Shape' and it should be a constant. Doing it this way makes the 4-sidedness a property of a square. This will translate nicely to another object, too.

Steve Hunter
Steve Hunter
57,712 Points

Hi Jared,

I'm not sure we want all instances of shape to have 4 sides, or do I misunderstand you?

Steve.

Jared Watkins
Jared Watkins
10,756 Points
Jared Watkins
Jared Watkins
10,756 Points

Hi Steve,

Yeah, I didn't say that very clearly.

The sides property should be in the Shape class since all shapes have some number of sides, including even 1 or 0. Initializing the number of sides to 4 should happen in the convenience initializer for the Square subclass since a square will always have 4 sides.

This way, not all instances of Shape will have 4 sides - only the Squares will.

Harold Davis
PLUS
Harold Davis
Courses Plus Student 14,604 Points
Harold Davis
Harold Davis
Courses Plus Student 14,604 Points

This will be an interesting assignment