code: public String hackResultName(AFuncDeclIR func) throws AnalysisException {
          SourceNode x = func.getSourceNode();
          if (x.getVdmNode() instanceof AImplicitFunctionDefinition) {
              AImplicitFunctionDefinition iFunc = (AImplicitFunctionDefinition) x.getVdmNode();
              return iFunc.getResult().getPattern().toString();
          }
          throw new AnalysisException("Expected AFuncDeclIR in implicit function source. Got: "
                  + x.getVdmNode().getClass().toString());
      }
docs: FIXME Unhack result name extraction for implicit functions