(*
    ||M||  This file is part of HELM, an Hypertextual, Electronic        
    ||A||  Library of Mathematics, developed at the Computer Science     
    ||T||  Department, University of Bologna, Italy.                     
    ||I||                                                                
    ||T||  HELM is free software; you can redistribute it and/or         
    ||A||  modify it under the terms of the GNU General Public License   
    \   /  version 2 or (at your option) any later version.              
     \ /   This software is distributed as is, NO WARRANTY.              
      V_______________________________________________________________ *)

module L = Log
module B = Bag
module E = BagEnvironment
module T = BagType

(* Interface functions ******************************************************)

(* to share *)
let type_check f g = function
   | None                    -> f None None
   | Some (a, uri, B.Abst t) ->
      let f tt obj = f (Some tt) (Some obj) in
      let f xt tt = E.set_obj (f tt) (a, uri, B.Abst xt) in
      L.loc := a; T.type_of f g B.empty_context t
   | Some (a, uri, B.Abbr t) ->
      let f tt obj = f (Some tt) (Some obj) in
      let f xt tt = E.set_obj (f tt) (a, uri, B.Abbr xt) in
      L.loc := a; T.type_of f g B.empty_context t
   | Some (a, uri, B.Void)   ->
      let f obj = f None (Some obj) in
      L.loc := a; E.set_obj f (a, uri, B.Void)