vtkwriter example cleaned up

src/vtkwriter.cc

@@ -38,7 +38,7 @@ static TestCases test_cases = {
 template <class GridView>
 void write (std::string prefix, GridView const& gridView)
 {
-#if ! DUNE_VERSION_NEWER(DUNE_FUNCTIONS, 2, 6)
+#if DUNE_VERSION_LT(DUNE_FUNCTIONS, 2, 6)
   using namespace BasisBuilder;
 #else
   using namespace BasisFactory;
@@ -77,7 +77,7 @@ int main (int argc, char** argv)
 {
   Dune::MPIHelper::instance(argc, argv);
 
-#ifdef HAVE_UG
+#if HAVE_UG
   // Test VtkWriter for UGGrid
   Hybrid::forEach(std::make_tuple(int_<2>{}, int_<3>{}), [](auto dim)
   {
@@ -91,10 +91,6 @@ int main (int argc, char** argv)
       write("vtkwriter_ug", gridPtr->leafGridView());
     }
   });
-#endif
-
-#ifdef HAVE_DUNE_ALUGRID
-
 #endif
 
   // Test VtkWriter for YaspGrid