diff --git a/model/fields.anubis b/model/fields.anubis
index d33aac9..77e2a3b 100644
--- a/model/fields.anubis
+++ b/model/fields.anubis
@@ -77,7 +77,24 @@ public define String
   )=
   to_String(attr)
 .
-  
+
+public define String
+  to_Anubis_source
+  (
+    List(HK_Foreign_Key_Active_Filter) active_filters
+  )=
+  "["+
+    join(", ",
+      map((HK_Foreign_Key_Active_Filter active_filter) |->
+        since active_filter is active_filter(column, fk_column),
+        "active_filter(\""+column+"\", \""+fk_column+"\")"
+        ,
+        active_filters
+      )
+    )+
+  "]"
+.
+
 define HK_Text_Field_Attr
   to_HK_Text_Field_Attr
   (
--
libgit2 0.21.4