Modules and scattered definitions

[algr]

The normal rules on scoping seem to imply that if B requires A and C requires B, but not A, then C will see B's definitions but not A's. Experiement suggests that C will see the names of scattered definitions introduced in A - and it can add to those definitions. So if A has something like

scattered enum E
enum clause E = E_one

B has

enum clause E = E_two

C has

enum clause E = E_three

Sail will accept this, and references to E in C will refer to the type name introduced in A. References to E_one in C will fail but Sail will helpfully point out that it is defined in A and will not allow it to be reused in C.

So it seems that scatter-defined names (is that the right terminology?) propagate through all imports, even indirect ones, in a way that normally defined names don't. I looked through the documentation but couldn't see this mentioned anywhere.

[Alasdair]

Should be fixed by #406

Currently the module system is WIP, so there are probably some similar issues. The in-scope check is done when accessing items from a typing context, so I probably need to go through and check all functions that are modifying things in the typing context to ensure they are not doing this in a way that breaks the rules.

[algr]

Thanks - I see "Enumeration E is not in scope" now. So that is consistent. I wasn't sure whether the original behavior was intentional.