Walter Bright Wrote:

> Robert Fraser wrote:
> > Out of curiosity, why doesn't return type deduction work for all functions (is this panned?). It seems to be possible to do:
> > 
> > auto foo()()
> > {
> >     return 10;
> > }
> > 
> > but not:
> > 
> > auto foo()
> > {
> >     return 10;
> > }
> 
> Good question!
> 
> Because deducing the return type requires semantic analysis, and for functions that introduces the old forward reference chicken-and-egg problem. This doesn't happen with function templates, because semantic analysis of them doesn't happen until later.

(Apologies for the web interface)

Any way to rewrite them as no-parameter templates automatically if possible and issue a sensible compiler message if they can't be (i.e. a virtual function).

Robert Fraser wrote:
> Any way to rewrite them as no-parameter templates automatically if possible and
> issue a sensible compiler message if they can't be (i.e. a virtual function).

It's not impossible, but there's too much else to do at the moment.