[swift-evolution] [Draft] Change @noreturn to unconstructible return type

[michael.peternell at gmx.at]

> Am 07.06.2016 um 22:56 schrieb Xiaodi Wu via swift-evolution <swift-evolution at swift.org>:
> 
> My response was simply to say that Never or NoReturn would in fact be a type, which is a good justification for looking like one. This behavior would be learnable and is theoretically sound, not an ad hoc idea being made up on the spot. No doubt, @noreturn is clearer today, but how much of that is because it's what we already know? And FWIW, "returns never" is hard to misinterpret, no?
> 

I disagree about the theoretical soundness here. It is implementable and doesn't introduce ambiguities, that's all IMHO.

-Michael