I'm trying to be good and arrange all my VIs appropriately in project
libraries*, marking each VI as public or private as I go. But I have
found that, when a polymorphic VI is called from outside a project
library, LabVIEW uses the access scope (public/private) from the
instance VI, not the polymorphic VI. It seems that the scope for the
polymorphic VI is simply ignored; you can even call a
private
polymorphic VI, as long as the instance VI is public. I assume this has
something to do with how the actual instances are dropped on the
diagram via the polymorphic VI. Is this the intended behavior? It just
doesn't seem like the way things should be, at least not in my head.
The attached example contains a project library (Case Lib.lvlib) with three VIs:
- Poly (private)
- Case DBL (public)
- Case I32 (private)
There
is also a Use Case DBL VI that calls Case DBL via Poly and a Use Case
I32 VI that calls Case I32 via Poly. Use Case DBL runs fine. Use Case
I32 has a broken arrow.
Originally, I had made a library with a
public polymorphic VI and private instances, because that's what makes
intuitive sense to me. Calling the polymorphic VI from another VI
didn't work because the instances were private.
(Cross-posted from
LAVA.)
