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iOS Swift Enums and Structs Structs and their Methods Struct Methods

Bool with nil?

when using optionals -> String or whatever, you can have return value of return nil

but with bools, someone somewhere said you can not use bools with nil or optionals I guess. that doesn't make sense, why is that? I get the feeling it can be done though.

struct Expense {
    var description: String
    var amount: Double = 0.0

    init (description: String) {
        self.description = description

    func calculateTaxes(percentage: Double) {

    // add the calculateTaxes method here
    // it should accept only one parameter named 'percentage' of type Double


it is from an earlier question so this code does not matter here, I just didn't feel like going all the way back to the if else question.

1 Answer

Brenden Konnagan
Brenden Konnagan
16,858 Points

Bool values can be optional. You can test this in a playground...

let testBool: Bool?

if let testBool = testBool {
print("not nil")
} else {

Any value type or class can be represented as optional in swift.