prune: switch to more modern '#pragma once'

diff --git a/contrib/prune/generic_list.h b/contrib/prune/generic_list.h
index 0e34afccb0a69e094af3db39030abceeb4f2d2b7..36d1ec2f0be632141e8b558dcf3f13038726b8f6 100644 (file)
--- a/contrib/prune/generic_list.h
+++ b/contrib/prune/generic_list.h
@@ -8,8 +8,7 @@
  * Contributors: Details at http://www.graphviz.org/
  *************************************************************************/
 
-#ifndef GENERIC_LIST_H
-#define GENERIC_LIST_H
+#pragma once
 
     typedef void *gl_data;
 
@@ -23,5 +22,3 @@
     extern generic_list_t *add_to_generic_list(generic_list_t * list,
                                               gl_data element);
     extern void free_generic_list(generic_list_t * list);
-
-#endif                         /* GENERIC_LIST_H */