Correct value of rawValue in an OptionSet?

Question

When working with an OptionSet, I believed that the rawValue always represented the combination of bits. In the example below, the "all" value does not have a correct rawValue. It is zero.

If placing a breakpoint in the init function, it will indeed get hit with a 0 value when initialising the "all" option set.

struct Options: OptionSet {

    init(rawValue: Int16) {
        self.rawValue = rawValue
    }
    
    let rawValue: Int16

    static let option1 = Options(rawValue:1)
    static let option2 = Options(rawValue:2)
    static let option3 = Options(rawValue:4)

    static let all = [option1,option2,option3]
}

To do something constructive, I have implemented the special init function that conforms to the ExpressibleByArrayLiteral protocol. But to no avail, as it is not called, when used in a static initialisation (however it will get called when used in a non-static initialisation).

struct Options: OptionSet {
...

    public init(arrayLiteral: Element...) {
        for element in arrayLiteral {
            
        }
    }

I don't understand the second part of your question, but in the first part you defined `all` incorrectly - it's now an `[Options]`, instead of `Options`. Did you mean for it to be `static let all: Options = [.option1, .option2, .option3]`? — New Dev, May 07 '21 at 12:30
Yes, I made a mistake there without thinking of the consequences — Developer-1, May 07 '21 at 12:58

score 1 · Accepted Answer · answered May 07 '21 at 12:37

1

You need to declare all to be of type Options

static let all: Options = [option1,option2,option3]

Example

print(Options.all) // prints Options(rawValue: 7)

answered May 07 '21 at 12:37

Joakim Danielson

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Correct value of rawValue in an OptionSet?

1 Answers1