Using self in init().

Question

For this code challenge why do you not use self.description? I  would think this block of code would work and do not understand why you would not use self.description, at least to keep the code neat.
init(red: Double, green: Double, blue: Double, alpha: Double) {
        self.red = red
        self.green = green
        self.blue = blue
        self.alpha = alpha
        description = "red: (red), green: (green), blue: (blue), alpha: (alpha)"
    }
The correct code is down below for the code challenge. So what is the big difference here? Also why do you have to do this?
"red: (red), green: (green)
init(red: Double, green: Double, blue: Double, alpha: Double) {
        self.red = red
        self.green = green
        self.blue = blue
        self.alpha = alpha
        description = "red: (red), green: (green), blue: (blue), alpha: (alpha)"
    }
```structs.swift
struct RGBColor {
    let red: Double
    let green: Double
    let blue: Double
    let alpha: Double
let description: String

// Add your code below
init(red: Double, green: Double, blue: Double, alpha: Double) {
    self.red = red
    self.green = green
    self.blue = blue
    self.alpha = alpha
    description = "red: \(red), green: \(green), blue: \(blue), alpha: \(alpha)"
}
}
```

Greg Kaleka · Accepted Answer

Hi Kurt,
In Swift, you're welcome to use self or not in initializers. The way you've written your init method, you need to use self for red, green, blue and alpha, because you've passed in parameters with those names. For description, though, you don't need to, because there's no ambiguity about which description you're referring to - there's only one. If you prefer, you're certainly welcome to use self.description, but it's not required by Swift.
Cheers,
-Greg

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Kurt Lyell

Kurt Lyell

Using self in init().

1 Answer

Greg Kaleka

Greg Kaleka