Imported Upstream version 8.5~beta1+dfsg

1 files changed, 137 insertions, 0 deletions

diff --git a/kernel/context.ml b/kernel/context.ml
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+(************************************************************************)
+(*  v      *   The Coq Proof Assistant  /  The Coq Development Team     *)
+(* <O___,, *   INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2015     *)
+(*   \VV/  **************************************************************)
+(*    //   *      This file is distributed under the terms of the       *)
+(*         *       GNU Lesser General Public License Version 2.1        *)
+(************************************************************************)
+
+(* Created by Jean-Christophe Filliâtre out of names.ml as part of the
+   rebuilding of Coq around a purely functional abstract type-checker,
+   Aug 1999 *)
+(* Miscellaneous extensions, restructurations and bug-fixes by Hugo
+   Herbelin and Bruno Barras *)
+
+(* This file defines types and combinators regarding indexes-based and
+   names-based contexts *)
+
+open Util
+open Names
+
+(***************************************************************************)
+(*     Type of assumptions                                                 *)
+(***************************************************************************)
+
+type named_declaration = Id.t * Constr.t option * Constr.t
+type named_list_declaration = Id.t list * Constr.t option * Constr.t
+type rel_declaration = Name.t * Constr.t option * Constr.t
+
+let map_named_declaration_skel f (id, (v : Constr.t option), ty) =
+  (id, Option.map f v, f ty)
+let map_named_list_declaration = map_named_declaration_skel
+let map_named_declaration = map_named_declaration_skel
+
+let map_rel_declaration = map_named_declaration
+
+let fold_named_declaration f (_, v, ty) a = f ty (Option.fold_right f v a)
+let fold_rel_declaration = fold_named_declaration
+
+let exists_named_declaration f (_, v, ty) = Option.cata f false v || f ty
+let exists_rel_declaration f (_, v, ty) = Option.cata f false v || f ty
+
+let for_all_named_declaration f (_, v, ty) = Option.cata f true v && f ty
+let for_all_rel_declaration f (_, v, ty) = Option.cata f true v && f ty
+
+let eq_named_declaration (i1, c1, t1) (i2, c2, t2) =
+  Id.equal i1 i2 && Option.equal Constr.equal c1 c2 && Constr.equal t1 t2
+
+let eq_rel_declaration (n1, c1, t1) (n2, c2, t2) =
+  Name.equal n1 n2 && Option.equal Constr.equal c1 c2 && Constr.equal t1 t2
+
+(***************************************************************************)
+(*     Type of local contexts (telescopes)                                 *)
+(***************************************************************************)
+
+(*s Signatures of ordered optionally named variables, intended to be
+   accessed by de Bruijn indices (to represent bound variables) *)
+
+type rel_context = rel_declaration list
+
+let empty_rel_context = []
+
+let add_rel_decl d ctxt = d::ctxt
+
+let rec lookup_rel n sign =
+  match n, sign with
+  | 1, decl :: _ -> decl
+  | n, _ :: sign -> lookup_rel (n-1) sign
+  | _, []        -> raise Not_found
+
+let rel_context_length = List.length
+
+let rel_context_nhyps hyps =
+  let rec nhyps acc = function
+    | [] -> acc
+    | (_,None,_)::hyps -> nhyps (1+acc) hyps
+    | (_,Some _,_)::hyps -> nhyps acc hyps in
+  nhyps 0 hyps
+
+let rel_context_tags ctx =
+  let rec aux l = function
+  | [] -> l
+  | (_,Some _,_)::ctx -> aux (true::l) ctx
+  | (_,None,_)::ctx -> aux (false::l) ctx
+  in aux [] ctx
+
+(*s Signatures of named hypotheses. Used for section variables and
+    goal assumptions. *)
+
+type named_context = named_declaration list
+type named_list_context = named_list_declaration list
+
+let empty_named_context = []
+
+let add_named_decl d sign = d::sign
+
+let rec lookup_named id = function
+  | (id',_,_ as decl) :: _ when Id.equal id id' -> decl
+  | _ :: sign -> lookup_named id sign
+  | [] -> raise Not_found
+
+let named_context_length = List.length
+let named_context_equal = List.equal eq_named_declaration
+
+let vars_of_named_context ctx =
+  List.fold_left (fun accu (id, _, _) -> Id.Set.add id accu) Id.Set.empty ctx
+
+let instance_from_named_context sign =
+  let filter = function
+  | (id, None, _) -> Some (Constr.mkVar id)
+  | (_, Some _, _) -> None
+  in
+  List.map_filter filter sign
+
+let fold_named_context f l ~init = List.fold_right f l init
+let fold_named_list_context f l ~init = List.fold_right f l init
+let fold_named_context_reverse f ~init l = List.fold_left f init l
+
+(*s Signatures of ordered section variables *)
+type section_context = named_context
+
+let fold_rel_context f l ~init:x = List.fold_right f l x
+let fold_rel_context_reverse f ~init:x l = List.fold_left f x l
+
+let map_context f l =
+  let map_decl (n, body_o, typ as decl) =
+    let body_o' = Option.smartmap f body_o in
+    let typ' = f typ in
+      if body_o' == body_o && typ' == typ then decl else
+        (n, body_o', typ')
+  in
+    List.smartmap map_decl l
+
+let map_rel_context = map_context
+let map_named_context = map_context
+
+let iter_rel_context f = List.iter (fun (_,b,t) -> f t; Option.iter f b)
+let iter_named_context f = List.iter (fun (_,b,t) -> f t; Option.iter f b)