title: CGAL join after difference
body: <p>I have a problem with CGAL, I divide a polygon (Polygon_with_holes_2) in different parts using intersection and difference functions and then I make a dissolve with the join function. But after using difference, the result of join function is not right, some lines hadn't been cut and it provokes a lot of errors.
  Does anybody knows how to solve this? It's a big problem and I've tried some solutions but anything works.</p>