[Oberon] Clarifying type compatibility in Oberon-07

[Jörg]

August

> 4. Ta and Tb are pointer types whose pointer base types are the same, or
> This rule is not needed, as it is covered by Assignment rule 4, assuming T is an extension of T itself.


When implementing assignment rule 4, you start with the type Te and go through the list of extension types until you reach Tv (assignment allowed) or the end of the list (assignment not allowed).
As in your example Te is Tv, your loop ends immediately with the result (assignment allowed).

br
Jörg