Quentin Lambert

What about that case: model M extends Main; model Main package Fluid = MFluid; extends Fluid.PartialTwoPort; extends Fluid.PartialStraightPipe; end Main; package MFluid partial model PartialStraightPipe end PartialStraightPipe; partial model PartialTwoPort...

Ultimately, I think we should forbid looking for extends name into extends because I don't want the following model to be valid: model Main package Fluid extends MFluid; partial model...

There are two different things here, the language design choice of requiring something to be evaluable, and the tool's ability to leave specific attributes unevaluated.

Note the definition of `mayOnleConnectOnce` for stream connectors, in Section 18.5.2: > For stream connectors (see chapter 15), the connection set has more than two elements whose flow > variable...

I like gerd's suggestion a lot.

Here is a model somewhat dual to the one above, which I would consider valid. ```modelica model Model2 connector C flow Real n_flow; Real p; end C; connector D stream...

A solution to this problem that I encountered in other libraries is to used overdetermined types with a residual size of `0`.

It is used in [the PowerGrids library](https://github.com/PowerGrids/PowerGrids/tree/develop) to define [ReferenceAngularVelocityPu](https://github.com/PowerGrids/PowerGrids/blob/d8786ab95d12ad6055a29821cf410a97971e6467/PowerGrids/Types.mo#L28C8-L28C34]. It is also used in the MSL to define [Modelica.Electrical.QuasiStatic.Types.Reference](https://github.com/modelica/ModelicaStandardLibrary/blob/master/Modelica/Electrical/QuasiStatic/Types/Reference.mo). In your case, that would mean defining the following type:...

Would you like me to make a pull request?

Here is the reference, I downloaded it from "modelica.org:/files/RegressionTesting/ReferenceResults/MSL" using the instructions available at: https://svn.modelica.org/projects/RegressionTesting/AccessInfo/read-access/README.html This is the v3.2.2+build.0-beta.3 version of the baseline: [AD_DA_conversion.zip](https://github.com/modelica/Modelica/files/1370974/AD_DA_conversion.zip)