this is wrong design concept...
because this way what you are implying is that once we have another model that you want to save in `uai` file format we'll have to add
```
void CUAIFile::save(COtherModel* m)
```
and implement it here...

i don't know if you can recall the reason why we wanted you to create a separate `CUAIFile`: to decouple it from a given model. now with this you are doing the same thing just in another class.

what you need to do actually is to design a `CUAIFile` that can represent an `UAI` file with some standard data structures... and in FactorGraph for example you would set these interim variables in `CUAIFile` in the desired way.