@noreturn property

[Iain Buclaw]

== Quote from Rainer Deyke (rainerd at eldwood.com)'s article
> On 10/21/2010 05:54, Iain Buclaw wrote:
> > @noreturn void fatal()
> > {
> >     print("Error");
> >     exit(1);
> > }
> > Thoughts?
> This looks wrong to me.  'fatal' returns type 'void', except that it
> doesn't.  I would prefer this:
> null_type fatal()
> {
>     print("Error");
>     exit(1);
> }
> Here 'null_type' is a type that has no values, as opposed to 'void'
> which has only one possible value.  No variables may be declared of type
> 'null_type'.  A function with a return type of 'null_type' never returns.
> Either way would work (and this feature is definitely useful), but
> 'null_type' has some significant advantages:
>   - It can be used in delegates and function pointers.
>   - It can be used in generic code where you don't know if a function
> will return or not.
>   - It makes for more concise code.
> Feel free to think of a better name than 'null_type'.

Not sure what you mean when you say that void has only one possible value. To me,
'void' for a function means something that does not return any value (or result).
Are you perhaps confusing it with to, lets say an 'int' function that is marked as
noreturn?

Regards
Iain