* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
-#ifndef PULSEVIEW_PV_VIEW_VIEWPORT_H
-#define PULSEVIEW_PV_VIEW_VIEWPORT_H
+#ifndef PULSEVIEW_PV_VIEW_VIEWPORT_HPP
+#define PULSEVIEW_PV_VIEW_VIEWPORT_HPP
+
+#include <boost/optional.hpp>