Lifetime tracking

[tsbockman via Digitalmars-d]

On Thursday, 2 June 2016 at 23:05:40 UTC, Timon Gehr wrote:
> Whenever the type checker is using a certain piece of 
> information to check validity of a program, there should be a 
> way to pass that kind of information across function 
> boundaries. Otherwise the type system is not modular. This is a 
> serious defect.

Would you mind giving a brief example of how that applies to 
`scope`?

(I'm asking for my own education; I have no personal opinion as 
to the right implementation at the moment.)