src/Pure/PIDE/document.ML

     let
       val id = Document_ID.print command_id;
       val span =
         Lazy.lazy (fn () =>
           Position.setmp_thread_data (Position.id_only id)
-            (fn () => Outer_Syntax.parse_tokens (Keyword.get_lexicons ()) (Position.id id) text) ());
+            (fn () => Outer_Syntax.scan (Keyword.get_lexicons ()) (Position.id id) text) ());
       val _ =
         Position.setmp_thread_data (Position.id_only id)
           (fn () => Output.status (Markup.markup_only Markup.accepted)) ();
       val commands' =
         Inttab.update_new (command_id, (name, command_blobs, span)) commands