Iterator<Label> lblIter = gr.pathroutines.computeAlphabet().iterator();
ErlangLabel lbl1 = (ErlangLabel)lblIter.next(),lbl2 = (ErlangLabel)lblIter.next();
// now mess up the name of the function,
FuncSignature fun2 = mod.sigs.get(lbl2.callName);
mod.sigs.put(lbl1.callName,fun2);// mess up behaviour
final LearnerGraph outcome = new LearnerGraph(gr.config);
checkForCorrectException(new whatToRun() { public @Override void run() {
AbstractLearnerGraph.interpretLabelsOnGraph(gr,outcome,mod.behaviour.new ConverterErlToMod());
}},IllegalArgumentException.class,"label already has a function assigned");