This is a bug in the old frontend and shouldn't work, the old frontend doesn't handle inheritance correctly. The variable must be reachable in the scope where it's used, but y is not declared inside the include model. In other words, the name resolution is done in the scope where a variable is used, not the scope it's inherited into.

thank you for the explanation. But this makes the use of partial models inattractive and the code longer.

It's not necessarily going to be (much) longer. You simply declare the variable in the partial model and modify it in the extends clause.

   record Soluble
    Real O2 "gO2/m3 dissolved oxygen";
    Real I "gCOD/m3 inert soluble organic material";
    Real S "gCOD/m3 readily biodegradable organic substances";
    Real NH "gN/m3 ammonium + ammonia N";
    Real NO "gN/m3 nitrite + nitrate N";
    Real ND "gN/m3 dissolved organic N";
    Real ALK "mol/m3 alkalinity";
  end Soluble;

  record Particulate
    Real H "gCOD/m3 heterotrophic bacteria";
    Real A "gCOD/m3 autotrophic bacteria";
    Real S "gCOD/m3 particulate slowly degradable substrates";
    Real I "gCOD/m3 inert particulate organic material";
    Real P "gCOD/m3 inert particulate organic matter resulting from decay";
    Real ND "gN/m3 particulate organic nitrogen";
  end Particulate;


SS in the partial model and S in the main model  are defined as record Soluble
XX in the partial model and X in the main model  are defined as record Particulate

in the main model the partial model is included in the way.
extends WWParameters(SS = S, XX = X);

leeds to an error message
Component SS of variability parameter has binding 'DN1.S' of higher variability continuous.

So it's really hard for me to make use of the partial model approach. So I am starting a rollback and copying all partial model code into the model where they are needed. Or do I misunderstanding the error massage?
By the way the stable release Connected to OpenModelica 1.14.0~dev.beta3 crashes frequently, so at the moment i am intending to go back to the release 1.13.2
Joachim

jobehrendt wrote:

leeds to an error message
Component SS of variability parameter has binding 'DN1.S' of higher variability continuous.

That has nothing to do with partial. The error means that you're trying to give a parameter a continuous binding, like this:

model A

  parameter Real x;

end A;



model B

  Real y;

  extends A(x = y); // Not allowed.

end B;

The value of a parameter doesn't change during the simulation, so trying to give it a binding equation that can change is not allowed.