__lldb_expr_146.GreekGod message

Swift Programming: The Big Nerd Ranch Guide (2nd E 18. Value vs. Reference Types
1

Can anyone explain to me why this is happening? I seem to remember an explanation earlier in the book, but I can’t seem to find it. Thanks for any help.

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Xcode’s playgrounds use something called a PlaygroundQuickLook to present information in the results sidebar.

Currently, GreekGod and Pantheon don’t really have any good way to provide a description to the sidebar. Thus, it defaults to the expression that you’re seeing.

Conform to CustomPlaygroundQuickLookable to provide more information to the results sidebar. For example,

extension GreekGod: CustomPlaygroundQuickLookable {
    
    var customPlaygroundQuickLook: PlaygroundQuickLook {
        let godMirror = Mirror(reflecting: self) // Provides an API to inspect an instance
        let type = godMirror.subjectType // The type of the instance
        return .text("\(type) named \(self.name)")
    }
    
}

You should see the sidebar display something like "GreekGod named Hecate" on this line: let hecate = GreekGod(name: "Hecate").

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