add string_to_<cenum> functions to match the <cenum>_to_string versions.

This helps with command-line parsing of cenums

CHANGES

@@ -1,3 +1,8 @@
+===== 0.5.1 (28-Sep-2012) =====
+
+* Add string_to_<cenum> function to match the <cenum>_to_string,
+  primarily to help with command-line parsing of enum arguments.
+
 ===== 0.5.0 (20-Sep-2012) =====
 
 * Add a signature generator for cstruct and cenum to permit

unix/lib_test/enum.ml

@@ -51,4 +51,5 @@ let _ =
   assert(foo32_to_int THREE32 = 1l);
   assert(int_to_foo32 3l = Some (TWO32));
   assert(int_to_foo32 1l = Some (THREE32));
+  assert(string_to_foo16 "ONE16" = Some ONE16);
   print_endline (foo8_to_string ONE8)

unix/syntax/pa_cstruct.ml

@@ -241,14 +241,18 @@ let output_enum _loc name fields width =
   ) fields) in
   let printers = mcOr_of_list (List.map (fun (f,_) ->
     <:match_case< $uid:f$ -> $str:f$ >>) fields) in
+  let parsers = mcOr_of_list (List.map (fun (f,_) ->
+    <:match_case< $str:f$ -> Some $uid:f$ >>) fields) in
   let getter x = sprintf "int_to_%s" x in
   let setter x = sprintf "%s_to_int" x in
   let printer x = sprintf "%s_to_string" x in
+  let parse x = sprintf "string_to_%s" x in
   <:str_item<
     type $lid:name$ = [ $decls$ ] ;
     value $lid:getter name$ x = match x with [ $getters$ ] ; 
     value $lid:setter name$ x = match x with [ $setters$ ] ;
-    value $lid:printer name$ x= match x with [ $printers$ ] ;
+    value $lid:printer name$ x = match x with [ $printers$ ] ;
+    value $lid:parse name$ x = match x with [ $parsers$ | _ -> None ] ;
   >>
 
 let output_enum_sig _loc name fields width =
@@ -264,13 +268,15 @@ let output_enum_sig _loc name fields width =
   let getter x = sprintf "int_to_%s" x in
   let setter x = sprintf "%s_to_int" x in
   let printer x = sprintf "%s_to_string" x in
+  let parse x = sprintf "string_to_%s" x in
   let ctyo = <:ctyp< option $lid:name$ >> in
   let cty = <:ctyp< $lid:name$ >> in
   <:sig_item<
     type $lid:name$ = [ $decls$ ] ;
     value $lid:getter name$ : $oty$ -> $ctyo$ ;
     value $lid:setter name$ : $cty$ -> $oty$ ;
-    value $lid:printer name$ : $cty$ -> string
+    value $lid:printer name$ : $cty$ -> string ;
+    value $lid:parse name$ : string -> option $cty$ ;
   >>
 
 EXTEND Gram