hphp/hack/src/typing/nast_check/const_prohibited_check.ml

   1 (*
   2  * Copyright (c) 2018, Facebook, Inc.
   3  * All rights reserved.
   4  *
   5  * This source code is licensed under the MIT license found in the
   6  * LICENSE file in the "hack" directory of this source tree.
   7  *
   8  *)
   9
  10 open Hh_prelude
  11 open Aast
  12 open Nast_check_env
  13 module SN = Naming_special_names
  14
  15 let has_const attrs = Naming_attributes.mem SN.UserAttributes.uaConst attrs
  16
  17 let error_if_const pos attrs =
  18   if has_const attrs then
  19     Errors.experimental_feature pos "The __Const attribute is not supported."
  20
  21 let handler =
  22   object
  23     inherit Nast_visitor.handler_base
  24
  25     method! at_class_ env c =
  26       (* Const handling:
  27        * disallow __Const attribute unless typechecker option is enabled
  28        *)
  29       let pos = fst c.c_name in
  30       if not (TypecheckerOptions.const_attribute (get_tcopt env)) then (
  31         error_if_const pos c.c_user_attributes;
  32         List.iter c.c_vars (fun cv -> error_if_const pos cv.cv_user_attributes)
  33       )
  34   end