--- camlp4/meta/pa_macro.ml	29 Oct 2003 22:49:48 -0000
+++ camlp4/meta/pa_macro.ml	31 Oct 2003 01:02:24 -0000
@@ -18,6 +18,7 @@
 
      IFDEF <uident> THEN <expression> [ ELSE <expression> ] ENDIF
      IFNDEF <uident> THEN <expression> [ ELSE <expression> ] ENDIF
+     DEFINE <lident> = <expression> in <expression>
      __FILE__
      __LOCATION__
 
@@ -36,6 +37,9 @@
   can use it in expressions *and* in patterns. If the expression defining
   the macro cannot be used as a pattern, there is an error message if
   it is used in a pattern.
+ 
+  You can also define a local macro in an expression usigng the DEFINE ... IN form.
+  Note that local macros have lowercase names and can not take parameters. 
 
   INCLUDE can be used to include a file with a number of macro definitions;
   however it can not have any non-macro toplevel items. The INCLUDE files
@@ -86,9 +90,15 @@
         try <:expr< $anti:List.assoc x env$ >> with
         [ Not_found -> e ]
     | <:expr< ($list:x$) >> -> <:expr< ($list:List.map loop x$) >>
+    | <:expr< do {$list:x$} >> -> <:expr< do {$list:List.map loop x$} >>
     | <:expr< { $list:pel$ } >> ->
         let pel = List.map (fun (p, e) -> (p, loop e)) pel in
         <:expr< { $list:pel$ } >>
+    | <:expr< try $e$ with [ $list:pel$ ] >> ->
+        let loop' = fun
+        [ (p, Some e1, e2) -> (p, Some (loop e1), loop e2)
+        | (p, None, e2) -> (p, None, loop e2) ] in
+        <:expr< try $loop e$ with [ $list: (List.map loop' pel)$ ] >>
     | e -> e ]
 ;
 
@@ -283,7 +293,10 @@
     [ [ "IFDEF"; i = uident; "THEN"; e1 = expr; e2 = else_expr ->
           if is_defined i then e1 else e2
       | "IFNDEF"; i = uident; "THEN"; e1 = expr; e2 = else_expr ->
-          if is_defined i then e2 else e1 ]]
+          if is_defined i then e2 else e1 
+      | "DEFINE"; i = LIDENT; "="; def = expr; "IN"; body = expr ->
+          subst loc [(i, def)] body
+      ]]
   ;
   expr: LEVEL "simple"
     [ [ LIDENT "__FILE__" -> <:expr< $str:Pcaml.input_file.val$ >>