Add constants to Ast_mapper.

parsing/ast_mapper.ml

@@ -42,6 +42,7 @@ type mapper = {
   class_type_declaration: mapper -> class_type_declaration
                           -> class_type_declaration;
   class_type_field: mapper -> class_type_field -> class_type_field;
+  constant: mapper -> constant -> constant;
   constructor_declaration: mapper -> constructor_declaration
                            -> constructor_declaration;
   expr: mapper -> expression -> expression;
@@ -85,6 +86,19 @@ let map_opt f = function None -> None | Some x -> Some (f x)
 
 let map_loc sub {loc; txt} = {loc = sub.location sub loc; txt}
 
+module C = struct
+  (* Constants *)
+
+  let map sub c = match c with
+    | Pconst_integer _
+    | Pconst_char _
+    | Pconst_float _
+      -> c
+    | Pconst_string (s, loc, quotation_delimiter) ->
+        let loc = sub.location sub loc in
+        Const.string ~loc ?quotation_delimiter s
+end
+
 module T = struct
   (* Type expressions for the core language *)
 
@@ -369,7 +383,7 @@ module E = struct
     let attrs = sub.attributes sub attrs in
     match desc with
     | Pexp_ident x -> ident ~loc ~attrs (map_loc sub x)
-    | Pexp_constant x -> constant ~loc ~attrs x
+    | Pexp_constant x -> constant ~loc ~attrs (sub.constant sub x)
     | Pexp_let (r, vbs, e) ->
         let_ ~loc ~attrs r (List.map (sub.value_binding sub) vbs)
           (sub.expr sub e)
@@ -463,7 +477,7 @@ module P = struct
     | Ppat_any -> any ~loc ~attrs ()
     | Ppat_var s -> var ~loc ~attrs (map_loc sub s)
     | Ppat_alias (p, s) -> alias ~loc ~attrs (sub.pat sub p) (map_loc sub s)
-    | Ppat_constant c -> constant ~loc ~attrs c
+    | Ppat_constant c -> constant ~loc ~attrs (sub.constant sub c)
     | Ppat_interval (c1, c2) -> interval ~loc ~attrs c1 c2
     | Ppat_tuple pl -> tuple ~loc ~attrs (List.map (sub.pat sub) pl)
     | Ppat_construct (l, p) ->
@@ -557,6 +571,7 @@ end
 
 let default_mapper =
   {
+    constant = C.map;
     structure = (fun this l -> List.map (this.structure_item this) l);
     structure_item = M.map_structure_item;
     module_expr = M.map;

parsing/ast_mapper.mli

@@ -71,6 +71,7 @@ type mapper = {
   class_type_declaration: mapper -> class_type_declaration
                           -> class_type_declaration;
   class_type_field: mapper -> class_type_field -> class_type_field;
+  constant: mapper -> constant -> constant;
   constructor_declaration: mapper -> constructor_declaration
                            -> constructor_declaration;
   expr: mapper -> expression -> expression;