Can signatures be made simpler and error messages be made better?

[Ola Fosheim Grøstad]

On Sunday, 13 June 2021 at 01:00:11 UTC, Elronnd wrote:
> That being said, I think the <= notation is appropriate.  In 
> particular, it mirrors type theory, where T≤U means that T is a 
> subtype of U.

Yes, although when I think of it. You might also want an abstract 
data type (ADT) to claim that objects it return references has 
the same lifetime as itself.

Which basically means the object will be destroyed by the 
destruction of the ADT.

Maybe one can define the lifetime equivalent of "critical 
sections", basically stating that "these objects" will outlive 
the entry of "that critical section". Or that "these objects" 
will not outlive the entry of "that critical section".

Hm.