discontinued somewhat pointless Par_List.map_name -- most of the time is spent in tokenization;

--- a/src/Pure/Thy/thy_load.ML	Sun Aug 21 13:42:55 2011 +0200
+++ b/src/Pure/Thy/thy_load.ML	Sun Aug 21 14:16:44 2011 +0200
@@ -175,9 +175,7 @@
     val spans = Source.exhaust (Thy_Syntax.span_source toks);
     val elements =
       Source.exhaust (Thy_Syntax.element_source (Source.of_list spans))
-      |> Par_List.map_name "Outer_Syntax.prepare_element"
-        (Outer_Syntax.prepare_element outer_syntax init)
-      |> flat;
+      |> maps (Outer_Syntax.prepare_element outer_syntax init);
 
     val _ = Present.theory_source name
       (fn () => HTML.html_mode (implode o map Thy_Syntax.present_span) spans);