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0 pointsChrisMarshallNY7mo ago0 comments

Swift has implicit unwrap (!), and explicit unwrap (?).

I don't like to use implicit unwrap. Even things that are guaranteed to be there, I treat as explicit (For example, (self.view?.isEnabled ?? false), in a view controller, instead of self.view.isEnabled).

I always redefine @IBOutlets from:

    @IBOutlet weak var someView!

to:

    @IBOutlet weak var someView?

I'm kind of a "belt & suspenders" type of guy.

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2 comments · 2 top-level

monocularvision7mo ago

So what happens if it ends up being nil? How does your app react?

In this particular case, I would rather crash. It’s easier to spot in a crash report and you get a nice stack trace.

Silent failure is ultimately terrible for users.

Note: for the things I control I try to very explicitly model state in such a way as I never need to force unwrap at all. But for things beyond my control like this situation, I would rather end the program than continue with a state of the world I don’t understand.

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groundzeros20157mo ago

This is terrible. The whole reason they introduced this is because IBOutlets would get silently disconnected and then in the field a user would complain that a feature stopped working.

Crash early, crash often. Find the bugs and bad assumptions.

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