When writing a large app in Swift, do I even need to use the "init" method at all?

Question

This is more of a concept question. Why bother with using init?

    class Person {
        var name:String
        var height:Double
        ...

        init(name: String) {
        self.name = name
        self.height:Double
        ...
    }

Why not just give everything a default value?

    var name = "Daniel"
    var height = 178.0

That way, I also won't have to worry about deciding between designated and 'convenience' inits because everything would just inherit from their superclass. Is there a reason for having this init method?

Does it allow for coding patterns that a strictly default-value-initialized app cannot achieve? Or is it for reasons like resource/memory management?

Answer 1

Lets assume you have a factory that builds cars and a tool / class "BuildCar" with the properties:

var numberOfTires =  4

var color = UIColor.red()

var maxSpeed = 100// mph

Now you want to build a whole lot of your fancy cars and use your 'BuildCar' Tool to do so. All you can do is build red cars that have 4 tires, and have a max speed of 100 mph.

But what if you want to build a new car? A blue one, with 4 tires and max speed of 120? If you used init, you could change the variables easily.