[vtkusers] Question about vtkIdList::IntersectWith(vtkIdList& otherIds)

[Sebastien.Valette at creatis.insa-lyon.fr]

Hi,

I am currently looking at the code of vtkIdList::IntersectWith(vtkIdList&
otherIds)

and I do not understand why it takes a reference to a vtkIdList instead of
a pointer. Does anyone have a clue? I am also wondering how to use it,
since the compiler complained at each of my trials to invoke it.

Thanks,

Sebastien