Index: openacs-4/packages/acs-tcl/tcl/object-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/tcl/object-procs.tcl,v
diff -u -r1.14.2.5 -r1.14.2.6
--- openacs-4/packages/acs-tcl/tcl/object-procs.tcl	6 Mar 2021 16:58:14 -0000	1.14.2.5
+++ openacs-4/packages/acs-tcl/tcl/object-procs.tcl	14 Jul 2022 16:55:16 -0000	1.14.2.6
@@ -179,6 +179,38 @@
     return [db_string object_exists {} -default 0]
 }
 
+ad_proc -private acs_object::is_type_p {
+    -object_id:required
+    -object_types:required
+    -no_hierarchy:boolean
+} {
+    Returns whether an object is of a given object type.
+} {
+    set object_types [ns_dbquotelist $object_types]
+    set no_hierarchy_p [expr {$no_hierarchy_p ? "t" : "f"}]
+    return [db_0or1row check_types [subst -nocommands {
+        with recursive hierarchy as
+        (
+         select o.object_type, t.supertype
+         from acs_objects o, acs_object_types t
+         where o.object_id = :object_id
+           and o.object_type = t.object_type
+
+         union
+
+         select t.object_type, t.supertype
+         from acs_object_types t,
+              hierarchy h
+         where :no_hierarchy_p = 'f'
+           and t.object_type = h.supertype
+           and h.object_type not in ($object_types)
+         )
+        select 1 from hierarchy
+        where object_type in ($object_types)
+        fetch first 1 rows only
+    }]]
+}
+
 ad_proc -public acs_object::set_context_id {
     {-object_id:required}
     {-context_id:required}