Using metatype Self to return current type

A helpful keyword in Swift is Self, which is a metatype that represents the current type. The current type may be the class, subclass or current implementer of a protocol, depending on where it is used.

A handy use-case for it is to avoid specifying generic placeholder types. Neat!

class ThreadRobot<CallerT: CallerRobot> {
    private let app = XCUIApplication()

    func tapCompleteButton() -> Self {
        app.otherElements["actionButtonRail"].buttons["Complete"].tap()
        return self
    }
}

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Thanks for reading and happy coding!

Hi, I hope you enjoyed the article. I am Andrew - a builder of apps and developer tools. Articles on the blog focus on all aspects of Android and iOS development using Kotlin and Swift.

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