Return values from auto function

[Andrey Zherikov]

On Friday, 6 November 2020 at 12:03:01 UTC, Paul Backus wrote:
> You can't. Both return values have to have the same type, which 
> means the failure function has to be able to return more than 
> one type, which means it has to be a template.

This issue seems hit the inability to implicitly convert custom 
types. May be it makes more sense to ask in a separate thread.