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0 pointssmallerfish2y ago0 comments

Or Kotlin's approach:

   fun getUser(userId: UUID): User?

You cannot treat this result value as a `User` in code that calls this; though, once you null check it in your service layer, you can pass it on as `User` in the not-null branch. Null is nothing to be afraid of if the language forces you to declare nullability and deal with it.

0 comments

andrekandre2y ago

this is a very common in obj-c too

on the other hand, depending on what your trying to do you might want to provide more context about what happened to the user/programmer

in swift you can change a throwing function to a nullable with `try?` so even if `getUser()` throws, you can keep it simple if thats what is appropriate

  guard let user = try? getUser(id: someUUID) else {
      return "user not found"
  }

as an aside, swift "throws" exceptions but these are just sugar for returning basically an Result<T,E> and compose much better than traditional stack unwinding exceptions imo

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