src/Pure/PIDE/resources.scala

     else if (Thy_Header.is_bootstrap(name.theory))
       Some(Document.Node.Header(List((import_name("", name, Thy_Header.PURE), Position.none))))
     else None
 
 
+  /* blobs */
+
+  def undefined_blobs(nodes: Document.Nodes): List[Document.Node.Name] =
+    (for {
+      (node_name, node) <- nodes.iterator
+      if !loaded_theories(node_name.theory)
+      cmd <- node.load_commands.iterator
+      name <- cmd.blobs_undefined.iterator
+    } yield name).toList
+
+
   /* document changes */
 
   def parse_change(
       reparse_limit: Int,
       previous: Document.Version,