Partial model using undeclared variable in equation works with OF but not with NF

[Karim Adbdelhak]

The model M from the following package was compilable in the old but not in the new frontend:

package partialstuff

partial model PM
equation
  v = 10;
end PM;

model M
  extends PM;
  Integer v;
end M;

end partialstuff;

The error message for the NF is

[1] 09:48:59 Translation Error
[partialstuff: 5:3-5:9]: Variable v not found in scope PM.

Is this expected behaviour? Does someone know what the specification says about this?

[Per Östlund]

Yes, that's the expected behaviour, the OF handles extends incorrectly. If you try it with e.g. Dymola you'll get the same error as with the NF. That the model is partial has no influence on how the lookup is done.

[Karim Adbdelhak]

Thanks!

[Francesco Casella]

The point of partial is to leave some behaviour (-> equations) unspecified, to be later filled in by child models.

To the contrary, writing equations with undeclared variables would be odd in a declarative language. Modelica is not Matlab :)