affine_constraints: hide another block of forward declarations

diff --git a/include/deal.II/lac/affine_constraints.h b/include/deal.II/lac/affine_constraints.h
index eaa2d95da87218b81756099fd36a0acc49b34f2b..104fff8be9b9553d6e8b8f62cbd688dfadf8c9e1 100644 (file)
--- a/include/deal.II/lac/affine_constraints.h
+++ b/include/deal.II/lac/affine_constraints.h
@@ -415,10 +415,6 @@ namespace internal
                  dealii::BlockVector<T> &                    vec);
   } // namespace AffineConstraintsImplementation
 } // namespace internal
-
-
-template <typename number>
-class AffineConstraints;
 #endif
 
 // TODO[WB]: We should have a function of the kind
@@ -2348,6 +2344,8 @@ AffineConstraints<number>::get_dof_values(
     }
 }
 
+// Forward declarations
+#ifndef DOXYGEN
 template <typename MatrixType>
 class BlockMatrixBase;
 template <typename SparsityPatternType>
@@ -2465,6 +2463,7 @@ namespace internal
 
   } // namespace AffineConstraints
 } // namespace internal
+#endif