require arg und result types on public features

[michaellilltokiwa]

Should we require explicit type for all arguments and the result for public features? I think this would lead to more consistent style and increase readability.

[fridis]

Missing argument types should definitely be forbidden, currently they should already cause an error unless there is a call to such a feature. As for result types: Yes, that would be good and the additional typing required is probably negligible.