Simplify cast to signed boundary_id

diff --git a/source/grid/grid_out.cc b/source/grid/grid_out.cc
index 1b13dc9b7a4cb6d459790f3c2da7f71abc1d7b25..770fe4de71f329918af902618d5330edefe1e251 100644 (file)
--- a/source/grid/grid_out.cc
+++ b/source/grid/grid_out.cc
@@ -947,13 +947,9 @@ GridOut::write_dx(const Triangulation<dim, spacedim> &tria,
           // Little trick to get -1 for the interior
           for (unsigned int f = 0; f < GeometryInfo<dim>::faces_per_cell; ++f)
             {
-              const types::boundary_id boundary_id =
-                cell->face(f)->boundary_id();
               out << ' '
-                  << (boundary_id == static_cast<types::boundary_id>(-1) ?
-                        -1 :
-                        static_cast<std::make_signed<types::boundary_id>::type>(
-                          boundary_id));
+                  << static_cast<std::make_signed<types::boundary_id>::type>(
+                       cell->face(f)->boundary_id());
             }
           out << '\n';
         }