[swift-evolution] Idea: change "@noreturn func f()" to "func f() noreturn"

[Radosław Pietruszewski]

I stand corrected! In this case, I change my position.

`func x() noreturn { … }` isn’t that bad on a second look.

— Radek

> On 26 Feb 2016, at 00:04, Jordan Rose <jordan_rose at apple.com> wrote:
> 
> "noreturn" is a part of a type signature; a @noreturn method cannot be overridden by a method that isn't @noreturn*, and you could have a closure that's guaranteed to not return.
> 
> * This isn't true in Objective-C, but it is in Swift.
> 
> Jordan
> 
>> On Feb 25, 2016, at 14:38, Radosław Pietruszewski via swift-evolution <swift-evolution at swift.org <mailto:swift-evolution at swift.org>> wrote:
>> 
>> The difference though is that throws/rethrows is a part of type signature, @noreturn isn’t and has no reason to be AFAICT. It’s just an attribute of the method…
>> 
>> — Radek
>> 
>>> On 25 Feb 2016, at 22:44, Jacob Bandes-Storch via swift-evolution <swift-evolution at swift.org <mailto:swift-evolution at swift.org>> wrote:
>>> 
>>> Premise: there are multiple ways of describing control-/data-flow when a function is called:
>>> 
>>>     func x() -> T   // x returns a value, of type T, to the caller
>>>     func x() throws  // x may throw an error to the caller
>>>     func x() throws -> T  // x may throw an error, and also return a value
>>>     func x(...) rethrows ... // if a closure argument can throw an error, x may also throw
>>>     @noreturn func x()  // x never returns to the caller
>>> 
>>> "noreturn" is currently spelled as an attribute, but like "throws" / "rethrows" / "-> T", it's really describing how control flow works.
>>> 
>>> IMO this calls for consistency: whatever happens "after" the function is called should appear "after" the parameter list.
>>> 
>>>     func x() noreturn {
>>>         ...
>>>     }
>>> 
>>> 
>>> Thoughts?
>>> 
>>> Jacob
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>> 
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