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(************************************************************************)
(*         *   The Coq Proof Assistant / The Coq Development Team       *)
(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2019       *)
(* <O___,, *       (see CREDITS file for the list of authors)           *)
(*   \VV/  **************************************************************)
(*    //   *    This file is distributed under the terms of the         *)
(*         *     GNU Lesser General Public License Version 2.1          *)
(*         *     (see LICENSE file for the text of the license)         *)
(************************************************************************)

open CErrors
open Util
open Names
open Univ
open Sorts
open Term
open Constr
open Context
open Vars
open Declarations
open Environ
open Reduction
open Inductive
open Type_errors

module RelDecl = Context.Rel.Declaration
module NamedDecl = Context.Named.Declaration

exception NotConvertibleVect of int

let conv_leq l2r env x y = default_conv CUMUL ~l2r env x y

let conv_leq_vecti env v1 v2 =
  Array.fold_left2_i
    (fun i _ t1 t2 ->
      try conv_leq false env t1 t2
      with NotConvertible -> raise (NotConvertibleVect i))
    ()
    v1
    v2

let check_constraints cst env = 
  if Environ.check_constraints cst env then ()
  else error_unsatisfied_constraints env cst

(* This should be a type (a priori without intention to be an assumption) *)
let check_type env c t =
  match kind(whd_all env t) with
  | Sort s -> s
  | _ -> error_not_type env (make_judge c t)

(* This should be a type intended to be assumed. The error message is
   not as useful as for [type_judgment]. *)
let infer_assumption env t ty =
  try
    let s = check_type env t ty in
    (match s with Sorts.SProp -> Irrelevant | _ -> Relevant)
  with TypeError _ ->
    error_assumption env (make_judge t ty)

let warn_bad_relevance_name = "bad-relevance"
let warn_bad_relevance =
  CWarnings.create ~name:warn_bad_relevance_name ~category:"debug" ~default:CWarnings.Disabled
    Pp.(function
        | None ->  str "Bad relevance in case annotation."
        | Some x -> str "Bad relevance for binder " ++ Name.print x.binder_name ++ str ".")

let warn_bad_relevance_ci ?loc () = warn_bad_relevance ?loc None
let warn_bad_relevance ?loc x = warn_bad_relevance ?loc (Some x)

let check_assumption env x t ty =
  let r = x.binder_relevance in
  let r' = infer_assumption env t ty in
  let x = if Sorts.relevance_equal r r'
    then x
    else (warn_bad_relevance x; {x with binder_relevance = r'})
  in
  x

(************************************************)
(* Incremental typing rules: builds a typing judgment given the *)
(* judgments for the subterms. *)

(*s Type of sorts *)

(* Prop and Set *)

let type1 = mkSort Sorts.type1

(* Type of Type(i). *)

let type_of_type u =
  let uu = Universe.super u in
    mkType uu

let type_of_sort = function
  | SProp | Prop | Set -> type1
  | Type u -> type_of_type u

(*s Type of a de Bruijn index. *)

let type_of_relative env n =
  try
    env |> lookup_rel n |> RelDecl.get_type |> lift n
  with Not_found ->
    error_unbound_rel env n

(* Type of variables *)
let type_of_variable env id =
  try named_type id env
  with Not_found ->
    error_unbound_var env id

(* Management of context of variables. *)

(* Checks if a context of variables can be instantiated by the
   variables of the current env.
   Order does not have to be checked assuming that all names are distinct *)
let check_hyps_inclusion env ?evars f c sign =
  let conv env a b = conv env ?evars a b in
  Context.Named.fold_outside
    (fun d1 () ->
      let open Context.Named.Declaration in
      let id = NamedDecl.get_id d1 in
      try
        let d2 = lookup_named id env in
        conv env (get_type d2) (get_type d1);
        (match d2,d1 with
        | LocalAssum _, LocalAssum _ -> ()
        | LocalAssum _, LocalDef _ ->
            (* This is wrong, because we don't know if the body is
               needed or not for typechecking: *) ()
        | LocalDef _, LocalAssum _ -> raise NotConvertible
        | LocalDef (_,b2,_), LocalDef (_,b1,_) -> conv env b2 b1);
      with Not_found | NotConvertible | Option.Heterogeneous ->
        error_reference_variables env id (f c))
    sign
    ~init:()

(* Instantiation of terms on real arguments. *)

(* Make a type polymorphic if an arity *)

(* Type of constants *)


let type_of_constant env (kn,_u as cst) =
  let cb = lookup_constant kn env in
  let () = check_hyps_inclusion env mkConstU cst cb.const_hyps in
  let ty, cu = constant_type env cst in
  let () = check_constraints cu env in
    ty

let type_of_constant_in env (kn,_u as cst) =
  let cb = lookup_constant kn env in
  let () = check_hyps_inclusion env mkConstU cst cb.const_hyps in
  constant_type_in env cst

(* Type of a lambda-abstraction. *)

(* [judge_of_abstraction env name var j] implements the rule

 env, name:typ |- j.uj_val:j.uj_type     env, |- (name:typ)j.uj_type : s
 -----------------------------------------------------------------------
          env |- [name:typ]j.uj_val : (name:typ)j.uj_type

  Since all products are defined in the Calculus of Inductive Constructions
  and no upper constraint exists on the sort $s$, we don't need to compute $s$
*)

let type_of_abstraction _env name var ty =
  mkProd (name, var, ty)

(* Type of an application. *)

let make_judgev c t = 
  Array.map2 make_judge c t

let rec check_empty_stack = function
| [] -> true
| CClosure.Zupdate _ :: s -> check_empty_stack s
| _ -> false

let type_of_apply env func funt argsv argstv =
  let open CClosure in
  let len = Array.length argsv in
  let infos = create_clos_infos all env in
  let tab = create_tab () in
  let rec apply_rec i typ =
    if Int.equal i len then term_of_fconstr typ
    else
      let typ, stk = whd_stack infos tab typ [] in
      (** The return stack is known to be empty *)
      let () = assert (check_empty_stack stk) in
      match fterm_of typ with
      | FProd (_, c1, c2, e) ->
        let arg = argsv.(i) in
        let argt = argstv.(i) in
        let c1 = term_of_fconstr c1 in
        begin match conv_leq false env argt c1 with
        | () -> apply_rec (i+1) (mk_clos (Esubst.subs_cons ([| inject arg |], e)) c2)
        | exception NotConvertible ->
          error_cant_apply_bad_type env
            (i+1,c1,argt)
            (make_judge func funt)
            (make_judgev argsv argstv)
        end
      | _ ->
        error_cant_apply_not_functional env
          (make_judge func funt)
          (make_judgev argsv argstv)
  in
  apply_rec 0 (inject funt)

(* Type of primitive constructs *)
let type_of_prim_type _env = function
  | CPrimitives.PT_int63 -> Constr.mkSet

let type_of_int env =
  match env.retroknowledge.Retroknowledge.retro_int63 with
  | Some c -> mkConst c
  | None -> CErrors.user_err Pp.(str"The type int must be registered before this construction can be typechecked.")

let type_of_prim env t =
  let int_ty = type_of_int env in
  let bool_ty () =
    match env.retroknowledge.Retroknowledge.retro_bool with
    | Some ((ind,_),_) -> Constr.mkInd ind
    | None -> CErrors.user_err Pp.(str"The type bool must be registered before this primitive.")
  in
  let compare_ty () =
    match env.retroknowledge.Retroknowledge.retro_cmp with
    | Some ((ind,_),_,_) -> Constr.mkInd ind
    | None -> CErrors.user_err Pp.(str"The type compare must be registered before this primitive.")
  in
  let pair_ty fst_ty snd_ty =
    match env.retroknowledge.Retroknowledge.retro_pair with
    | Some (ind,_) -> Constr.mkApp(Constr.mkInd ind, [|fst_ty;snd_ty|])
    | None -> CErrors.user_err Pp.(str"The type pair must be registered before this primitive.")
  in
  let carry_ty int_ty =
    match env.retroknowledge.Retroknowledge.retro_carry with
    | Some ((ind,_),_) -> Constr.mkApp(Constr.mkInd ind, [|int_ty|])
    | None -> CErrors.user_err Pp.(str"The type carry must be registered before this primitive.")
  in
  let rec nary_int63_op arity ty =
    if Int.equal arity 0 then ty
      else Constr.mkProd(Context.nameR (Id.of_string "x"), int_ty, nary_int63_op (arity-1) ty)
  in
  let return_ty =
    let open CPrimitives in
    match t with
    | Int63head0
    | Int63tail0
    | Int63add
    | Int63sub
    | Int63mul
    | Int63div
    | Int63mod
    | Int63lsr
    | Int63lsl
    | Int63land
    | Int63lor
    | Int63lxor
    | Int63addMulDiv -> int_ty
    | Int63eq
    | Int63lt
    | Int63le -> bool_ty ()
    | Int63mulc
    | Int63div21
    | Int63diveucl -> pair_ty int_ty int_ty
    | Int63addc
    | Int63subc
    | Int63addCarryC
    | Int63subCarryC -> carry_ty int_ty
    | Int63compare -> compare_ty ()
  in
  nary_int63_op (CPrimitives.arity t) return_ty

let type_of_prim_or_type env = let open CPrimitives in
  function
  | OT_type t -> type_of_prim_type env t
  | OT_op op -> type_of_prim env op

let judge_of_int env i =
  make_judge (Constr.mkInt i) (type_of_int env)

(* Type of product *)

let sort_of_product env domsort rangsort =
  match (domsort, rangsort) with
    | (_, SProp) | (SProp, _) -> rangsort
    (* Product rule (s,Prop,Prop) *)
    | (_,       Prop)  -> rangsort
    (* Product rule (Prop/Set,Set,Set) *)
    | ((Prop | Set),  Set) -> rangsort
    (* Product rule (Type,Set,?) *)
    | (Type u1, Set) ->
        if is_impredicative_set env then
          (* Rule is (Type,Set,Set) in the Set-impredicative calculus *)
          rangsort
        else
          (* Rule is (Type_i,Set,Type_i) in the Set-predicative calculus *)
          Sorts.sort_of_univ (Universe.sup Universe.type0 u1)
    (* Product rule (Prop,Type_i,Type_i) *)
    | (Set,  Type u2)  -> Sorts.sort_of_univ (Universe.sup Universe.type0 u2)
    (* Product rule (Prop,Type_i,Type_i) *)
    | (Prop, Type _)  -> rangsort
    (* Product rule (Type_i,Type_i,Type_i) *)
    | (Type u1, Type u2) -> Sorts.sort_of_univ (Universe.sup u1 u2)

(* [judge_of_product env name (typ1,s1) (typ2,s2)] implements the rule

    env |- typ1:s1       env, name:typ1 |- typ2 : s2
    -------------------------------------------------------------------------
         s' >= (s1,s2), env |- (name:typ)j.uj_val : s'

  where j.uj_type is convertible to a sort s2
*)
let type_of_product env _name s1 s2 =
  let s = sort_of_product env s1 s2 in
    mkSort s

(* Type of a type cast *)

(* [judge_of_cast env (c,typ1) (typ2,s)] implements the rule

    env |- c:typ1    env |- typ2:s    env |- typ1 <= typ2
    ---------------------------------------------------------------------
         env |- c:typ2
*)

let check_cast env c ct k expected_type =
  try
    match k with
    | VMcast ->
      Vconv.vm_conv CUMUL env ct expected_type
    | DEFAULTcast ->
      default_conv ~l2r:false CUMUL env ct expected_type
    | REVERTcast ->
      default_conv ~l2r:true CUMUL env ct expected_type
    | NATIVEcast ->
      let sigma = Nativelambda.empty_evars in
      Nativeconv.native_conv CUMUL sigma env ct expected_type
  with NotConvertible ->
    error_actual_type env (make_judge c ct) expected_type

(* Inductive types. *)

(* The type is parametric over the uniform parameters whose conclusion
   is in Type; to enforce the internal constraints between the
   parameters and the instances of Type occurring in the type of the
   constructors, we use the level variables _statically_ assigned to
   the conclusions of the parameters as mediators: e.g. if a parameter
   has conclusion Type(alpha), static constraints of the form alpha<=v
   exist between alpha and the Type's occurring in the constructor
   types; when the parameters is finally instantiated by a term of
   conclusion Type(u), then the constraints u<=alpha is computed in
   the App case of execute; from this constraints, the expected
   dynamic constraints of the form u<=v are enforced *)

let type_of_inductive_knowing_parameters env (ind,u as indu) args =
  let (mib,_mip) as spec = lookup_mind_specif env ind in
  check_hyps_inclusion env mkIndU indu mib.mind_hyps;
  let t,cst = Inductive.constrained_type_of_inductive_knowing_parameters 
    env (spec,u) args
  in
  check_constraints cst env;
  t

let type_of_inductive env (ind,u as indu) =
  let (mib,mip) = lookup_mind_specif env ind in
  check_hyps_inclusion env mkIndU indu mib.mind_hyps;
  let t,cst = Inductive.constrained_type_of_inductive env ((mib,mip),u) in
  check_constraints cst env;
  t

(* Constructors. *)

let type_of_constructor env (c,_u as cu) =
  let () =
    let ((kn,_),_) = c in
    let mib = lookup_mind kn env in
    check_hyps_inclusion env mkConstructU cu mib.mind_hyps
  in
  let specif = lookup_mind_specif env (inductive_of_constructor c) in
  let t,cst = constrained_type_of_constructor cu specif in
  let () = check_constraints cst env in
  t

(* Case. *)

let check_branch_types env (ind,u) c ct lft explft =
  try conv_leq_vecti env lft explft
  with
      NotConvertibleVect i ->
        error_ill_formed_branch env c ((ind,i+1),u) lft.(i) explft.(i)
    | Invalid_argument _ ->
        error_number_branches env (make_judge c ct) (Array.length explft)

let type_of_case env ci p pt c ct _lf lft =
  let (pind, _ as indspec) =
    try find_rectype env ct
    with Not_found -> error_case_not_inductive env (make_judge c ct) in
  let _, sp = try dest_arity env pt
    with NotArity -> error_elim_arity env pind c (make_judge p pt) None in
  let rp = Sorts.relevance_of_sort sp in
  let ci = if ci.ci_relevance == rp then ci
    else (warn_bad_relevance_ci (); {ci with ci_relevance=rp})
  in
  let () = check_case_info env pind rp ci in
  let (bty,rslty) =
    type_case_branches env indspec (make_judge p pt) c in
  let () = check_branch_types env pind c ct lft bty in
  ci, rslty

let type_of_projection env p c ct =
  let pty = lookup_projection p env in
  let (ind,u), args =
    try find_rectype env ct
    with Not_found -> error_case_not_inductive env (make_judge c ct)
  in
  assert(eq_ind (Projection.inductive p) ind);
  let ty = Vars.subst_instance_constr u pty in
  substl (c :: CList.rev args) ty
      

(* Fixpoints. *)

(* Checks the type of a general (co)fixpoint, i.e. without checking *)
(* the specific guard condition. *)

let check_fixpoint env lna lar vdef vdeft =
  let lt = Array.length vdeft in
  assert (Int.equal (Array.length lar) lt);
  try
    conv_leq_vecti env vdeft (Array.map (fun ty -> lift lt ty) lar)
  with NotConvertibleVect i ->
    error_ill_typed_rec_body env i lna (make_judgev vdef vdeft) lar

(* Global references *)

let type_of_global_in_context env r =
  let open Names.GlobRef in
  match r with
  | VarRef id -> Environ.named_type id env, Univ.AUContext.empty
  | ConstRef c ->
    let cb = Environ.lookup_constant c env in
    let univs = Declareops.constant_polymorphic_context cb in
    cb.Declarations.const_type, univs
  | IndRef ind ->
    let (mib,_ as specif) = Inductive.lookup_mind_specif env ind in
    let univs = Declareops.inductive_polymorphic_context mib in
    let inst = Univ.make_abstract_instance univs in
    let env = Environ.push_context ~strict:false (Univ.AUContext.repr univs) env in
    Inductive.type_of_inductive env (specif, inst), univs
  | ConstructRef cstr ->
    let (mib,_ as specif) =
      Inductive.lookup_mind_specif env (inductive_of_constructor cstr)
    in
    let univs = Declareops.inductive_polymorphic_context mib in
    let inst = Univ.make_abstract_instance univs in
    Inductive.type_of_constructor (cstr,inst) specif, univs

(************************************************************************)
(************************************************************************)

let check_binder_annot s x =
  let r = x.binder_relevance in
  let r' = Sorts.relevance_of_sort s in
  if r' == r
  then x
  else (warn_bad_relevance x; {x with binder_relevance = r'})

(* The typing machine. *)
    (* ATTENTION : faudra faire le typage du contexte des Const,
    Ind et Constructsi un jour cela devient des constructions
    arbitraires et non plus des variables *)
let rec execute env cstr =
  let open Context.Rel.Declaration in
  match kind cstr with
    (* Atomic terms *)
    | Sort s ->
      (match s with
       | SProp -> if not (Environ.sprop_allowed env) then error_disallowed_sprop env
       | _ -> ());
      cstr, type_of_sort s

    | Rel n ->
      cstr, type_of_relative env n

    | Var id ->
      cstr, type_of_variable env id

    | Const c ->
      cstr, type_of_constant env c
        
    | Proj (p, c) ->
      let c', ct = execute env c in
      let cstr = if c == c' then cstr else mkProj (p,c') in
      cstr, type_of_projection env p c' ct

    (* Lambda calculus operators *)
    | App (f,args) ->
      let args', argst = execute_array env args in
        let f', ft =
          match kind f with
          | Ind ind when Environ.template_polymorphic_pind ind env ->
            let args = Array.map (fun t -> lazy t) argst in
              f, type_of_inductive_knowing_parameters env ind args
          | _ ->
            (* No template polymorphism *)
            execute env f
        in
        let cstr = if f == f' && args == args' then cstr else mkApp (f',args') in
        cstr, type_of_apply env f' ft args' argst

    | Lambda (name,c1,c2) ->
      let c1', s = execute_is_type env c1 in
      let name' = check_binder_annot s name in
      let env1 = push_rel (LocalAssum (name',c1')) env in
      let c2', c2t = execute env1 c2 in
      let cstr = if name == name' && c1 == c1' && c2 == c2' then cstr else mkLambda(name',c1',c2') in
      cstr, type_of_abstraction env name' c1 c2t

    | Prod (name,c1,c2) ->
      let c1', vars = execute_is_type env c1 in
      let name' = check_binder_annot vars name in
      let env1 = push_rel (LocalAssum (name',c1')) env in
      let c2', vars' = execute_is_type env1 c2 in
      let cstr = if name == name' && c1 == c1' && c2 == c2' then cstr else mkProd(name',c1',c2') in
      cstr, type_of_product env name' vars vars'

    | LetIn (name,c1,c2,c3) ->
      let c1', c1t = execute env c1 in
      let c2', c2s = execute_is_type env c2 in
      let name' = check_binder_annot c2s name in
      let () = check_cast env c1' c1t DEFAULTcast c2' in
      let env1 = push_rel (LocalDef (name',c1',c2')) env in
      let c3', c3t = execute env1 c3 in
      let cstr = if name == name' && c1 == c1' && c2 == c2' && c3 == c3' then cstr
        else mkLetIn(name',c1',c2',c3')
      in
      cstr, subst1 c1 c3t

    | Cast (c,k,t) ->
      let c', ct = execute env c in
      let t', _ts = execute_is_type env t in
      let () = check_cast env c' ct k t' in
      let cstr = if c == c' && t == t' then cstr else mkCast(c',k,t') in
      cstr, t'

    (* Inductive types *)
    | Ind ind ->
      cstr, type_of_inductive env ind

    | Construct c ->
      cstr, type_of_constructor env c

    | Case (ci,p,c,lf) ->
        let c', ct = execute env c in
        let p', pt = execute env p in
        let lf', lft = execute_array env lf in
        let ci', t = type_of_case env ci p' pt c' ct lf' lft in
        let cstr = if ci == ci' && c == c' && p == p' && lf == lf' then cstr
          else mkCase(ci',p',c',lf')
        in
        cstr, t

    | Fix ((_vn,i as vni),recdef as fix) ->
      let (fix_ty,recdef') = execute_recdef env recdef i in
      let cstr, fix = if recdef == recdef' then cstr, fix else
          let fix = (vni,recdef') in mkFix fix, fix
      in
      check_fix env fix; cstr, fix_ty
          
    | CoFix (i,recdef as cofix) ->
      let (fix_ty,recdef') = execute_recdef env recdef i in
      let cstr, cofix = if recdef == recdef' then cstr, cofix else
          let cofix = (i,recdef') in mkCoFix cofix, cofix
      in
      check_cofix env cofix; cstr, fix_ty

    (* Primitive types *)
    | Int _ -> cstr, type_of_int env

    (* Partial proofs: unsupported by the kernel *)
    | Meta _ ->
        anomaly (Pp.str "the kernel does not support metavariables.")

    | Evar _ ->
        anomaly (Pp.str "the kernel does not support existential variables.")

and execute_is_type env constr =
  let c, t = execute env constr in
    c, check_type env constr t

and execute_recdef env (names,lar,vdef as recdef) i =
  let lar', lart = execute_array env lar in
  let names' = Array.Smart.map_i (fun i na -> check_assumption env na lar'.(i) lart.(i)) names in
  let env1 = push_rec_types (names',lar',vdef) env in (* vdef is ignored *)
  let vdef', vdeft = execute_array env1 vdef in
  let () = check_fixpoint env1 names' lar' vdef' vdeft in
  let recdef = if names == names' && lar == lar' && vdef == vdef' then recdef else (names',lar',vdef') in
    (lar'.(i),recdef)

and execute_array env cs =
  let tys = Array.make (Array.length cs) mkProp in
  let cs = Array.Smart.map_i (fun i c -> let c, ty = execute env c in tys.(i) <- ty; c) cs in
  cs, tys

(* Derived functions *)

let check_wellformed_universes env c =
  let univs = universes_of_constr c in
  try UGraph.check_declared_universes (universes env) univs
  with UGraph.UndeclaredLevel u ->
    error_undeclared_universe env u

let infer env constr =
  let () = check_wellformed_universes env constr in
  let constr, t = execute env constr in
  make_judge constr t

let infer = 
  if Flags.profile then
    let infer_key = CProfile.declare_profile "Fast_infer" in
      CProfile.profile2 infer_key (fun b c -> infer b c)
  else (fun b c -> infer b c)

let assumption_of_judgment env {uj_val=c; uj_type=t} =
  infer_assumption env c t

let type_judgment env {uj_val=c; uj_type=t} =
  let s = check_type env c t in
  {utj_val = c; utj_type = s }

let infer_type env constr =
  let () = check_wellformed_universes env constr in
  let constr, t = execute env constr in
  let s = check_type env constr t in
  {utj_val = constr; utj_type = s}

(* Typing of several terms. *)

let check_context env rels =
  let open Context.Rel.Declaration in
  Context.Rel.fold_outside (fun d (env,rels) ->
    match d with
      | LocalAssum (x,ty) ->
        let jty = infer_type env ty in
        let x = check_binder_annot jty.utj_type x in
        push_rel d env, LocalAssum (x,jty.utj_val) :: rels
      | LocalDef (x,bd,ty) ->
        let j1 = infer env bd in
        let jty = infer_type env ty in
        conv_leq false env j1.uj_type ty;
        let x = check_binder_annot jty.utj_type x in
        push_rel d env, LocalDef (x,j1.uj_val,jty.utj_val) :: rels)
    rels ~init:(env,[])

let judge_of_prop = make_judge mkProp type1
let judge_of_set = make_judge mkSet type1
let judge_of_type u = make_judge (mkType u) (type_of_type u)

let judge_of_relative env k = make_judge (mkRel k) (type_of_relative env k)

let judge_of_variable env x = make_judge (mkVar x) (type_of_variable env x)

let judge_of_constant env cst = make_judge (mkConstU cst) (type_of_constant env cst)

let judge_of_projection env p cj =
  make_judge (mkProj (p,cj.uj_val)) (type_of_projection env p cj.uj_val cj.uj_type)

let dest_judgev v =
  Array.map j_val v, Array.map j_type v

let judge_of_apply env funj argjv =
  let args, argtys = dest_judgev argjv in
  make_judge (mkApp (funj.uj_val, args)) (type_of_apply env funj.uj_val funj.uj_type args argtys)

(* let judge_of_abstraction env x varj bodyj = *)
(*   make_judge (mkLambda (x, varj.utj_val, bodyj.uj_val)) *)
(*              (type_of_abstraction env x varj.utj_val bodyj.uj_type) *)

(* let judge_of_product env x varj outj = *)
(*   make_judge (mkProd (x, varj.utj_val, outj.utj_val)) *)
(*              (mkSort (sort_of_product env varj.utj_type outj.utj_type)) *)

(* let judge_of_letin env name defj typj j = *)
(*   make_judge (mkLetIn (name, defj.uj_val, typj.utj_val, j.uj_val)) *)
(*              (subst1 defj.uj_val j.uj_type) *)

let judge_of_cast env cj k tj =
  let () = check_cast env cj.uj_val cj.uj_type k tj.utj_val in
  let c = match k with | REVERTcast -> cj.uj_val | _ -> mkCast (cj.uj_val, k, tj.utj_val) in
  make_judge c tj.utj_val

let judge_of_inductive env indu =
  make_judge (mkIndU indu) (type_of_inductive env indu)

let judge_of_constructor env cu =
  make_judge (mkConstructU cu) (type_of_constructor env cu)

let judge_of_case env ci pj cj lfj =
  let lf, lft = dest_judgev lfj in
  let ci, t = type_of_case env ci pj.uj_val pj.uj_type cj.uj_val cj.uj_type lf lft in
  make_judge (mkCase (ci, (*nf_betaiota*) pj.uj_val, cj.uj_val, lft)) t

(* Building type of primitive operators and type *)

let check_primitive_type env op_t t =
  let inft = type_of_prim_or_type env op_t in
  try default_conv ~l2r:false CUMUL env inft t
  with NotConvertible -> error_incorrect_primitive env (make_judge op_t inft) t