@Override
  public PsiParameterStub findParameter(final int idx) {
    PsiParameterListStub list = null;
    for (StubElement<?> child : getChildrenStubs()) {
      if (child instanceof PsiParameterListStub) {
        list = (PsiParameterListStub)child;
        break;
      }
    }

    if (list != null) {
      final List<StubElement<?>> params = list.getChildrenStubs();
      return (PsiParameterStub)params.get(idx);
    }

    throw new RuntimeException("No parameter(s) [yet?]");
  }
@Override
  public PsiParameterStub findParameter(final int idx)