Introducing an “Unwrap or Throw” operator

Evolution Pitches
11

I might misunderstand here something. I still don't see why @autoclosure should not be able to capture whole statements.

// everyone knows that @autoclosure will wrap everything into a block / closure
throw myError ---> { throw myError }

We already can use the closure syntax without @autoclosure and get the expected result. All we want to achieve here is to make it a bit more convenient and implicit.

And if we're at it, I think it might be a great idea to introduce a tiny breaking change to the language for Swift 6:

let foo = {
  throw MyError.bar
}

// currently: `foo: () throws -> Void`
// after: `foo: () throws -> Never` 
// If the compiler knows that every exit path of a function throws
// the function itself should never return, hence `Never`

let bar: () throws -> Void = {
  if someCondition {
    print("swift")
  } else {
    throw MyError.bar
  }
}

I move the last idea into its own pitch. ;)

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