diff --git a/src/structs.h b/src/structs.h
index ae2c0b8..d6f4988 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -769,6 +769,7 @@
 // Values for the flags argument of ml_delete_flags().
 #define ML_DEL_MESSAGE	    1	// may give a "No lines in buffer" message
 #define ML_DEL_UNDO	    2	// called from undo, do not update textprops
+#define ML_DEL_NOPROP	    4	// splitting data block, do not update textprops
 
 // Values for the flags argument of ml_append_int().
 #define ML_APPEND_NEW	    1	// starting to edit a new file