Index: library/lib/doc-tools.tcl
===================================================================
diff -u -r239888ee1ee6ed6d7b9afa5e170f49c5224a186d -rcc94b154709f9bd3393fbbdb9af982a30b57dee0
--- library/lib/doc-tools.tcl	(.../doc-tools.tcl)	(revision 239888ee1ee6ed6d7b9afa5e170f49c5224a186d)
+++ library/lib/doc-tools.tcl	(.../doc-tools.tcl)	(revision cc94b154709f9bd3393fbbdb9af982a30b57dee0)
@@ -517,7 +517,7 @@
       next [list [list @doc:optional __initcmd:initcmd,optional]]
     }
 
-    :class-object attribute current_project:object,type=::nx::doc::@project,allowempty
+    :class-object attribute current_project:object,type=::nx::doc::@project,0..1
     :public forward current_project [current] %method
 
     :attribute partof:object,type=::nx::doc::StructuredEntity