docs: public void addControlDependency(SDVariable controlDependency){
          String cdN = controlDependency.getVarName();
          String n = this.getVarName();
          Variable v = sameDiff.getVariables().get(n);
          if(v.getControlDeps() == null)
              v.setControlDeps(new ArrayList<String>());
          if(!v.getControlDeps().contains(cdN))
              v.getControlDeps().add(cdN);
  
          Variable v2 = sameDiff.getVariables().get(cdN);
          if(v2.getControlDepsForVar() == null)
              v2.setControlDepsForVar(new ArrayList<String>());
          if(!v2.getControlDepsForVar().contains(n))
              v2.getControlDepsForVar().add(n);
      }