Pointer value representation in Algol68?

Algol68 has rules about "scope" of REF REF values
to prevent pointer "up" the stack to something deallocated.
I can not take a reference to a local variable
and pass it to a more global scope. (I thibk thats the word?)


Even when I pass both the source and destination objects
to another procedure.


This means at run time for:
rri := ri;
The scopes of rri and ri must be compared.
If both are parameters then they must carry their scope information
with them.
I can not see how this can be done using a single "word"
as someone indicated many weeks ago in this group.


As I see it there are two "words", one for the pointer and one for the
"stack frame scope identifier".


Ken Walter WEEKDAY

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