[api] [parsing] Move Egram* to `vernac/`

The extension mechanism is specific to metasyntax and vernacinterp,
thus it makes sense to place them next to each other.

We also fix the META entry for the `grammar` camlp5 plugin.

7 files changed, 1871 insertions, 4 deletions

diff --git a/vernac/egramcoq.ml b/vernac/egramcoq.ml
new file mode 100644
index 000000000..5f63d21c4
--- /dev/null
+++ b/vernac/egramcoq.ml
@@ -0,0 +1,483 @@
+(************************************************************************)
+(*         *   The Coq Proof Assistant / The Coq Development Team       *)
+(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2018       *)
+(* <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 Pcoq
+open Constrexpr
+open Notation_term
+open Extend
+open Libnames
+open Names
+
+(**********************************************************************)
+(* This determines (depending on the associativity of the current
+   level and on the expected associativity) if a reference to constr_n is
+   a reference to the current level (to be translated into "SELF" on the
+   left border and into "constr LEVEL n" elsewhere), to the level below
+   (to be translated into "NEXT") or to an below wrt associativity (to be
+   translated in camlp5 into "constr" without level) or to another level
+   (to be translated into "constr LEVEL n")
+
+   The boolean is true if the entry was existing _and_ empty; this to
+   circumvent a weakness of camlp5 whose undo mechanism is not the
+   converse of the extension mechanism *)
+
+let constr_level = string_of_int
+
+let default_levels =
+  [200,Extend.RightA,false;
+   100,Extend.RightA,false;
+   99,Extend.RightA,true;
+   90,Extend.RightA,true;
+   10,Extend.LeftA,false;
+   9,Extend.RightA,false;
+   8,Extend.RightA,true;
+   1,Extend.LeftA,false;
+   0,Extend.RightA,false]
+
+let default_pattern_levels =
+  [200,Extend.RightA,true;
+   100,Extend.RightA,false;
+   99,Extend.RightA,true;
+   90,Extend.RightA,true;
+   10,Extend.LeftA,false;
+   1,Extend.LeftA,false;
+   0,Extend.RightA,false]
+
+let default_constr_levels = (default_levels, default_pattern_levels)
+
+(* At a same level, LeftA takes precedence over RightA and NoneA *)
+(* In case, several associativity exists for a level, we make two levels, *)
+(* first LeftA, then RightA and NoneA together *)
+
+let admissible_assoc = function
+  | Extend.LeftA, Some (Extend.RightA | Extend.NonA) -> false
+  | Extend.RightA, Some Extend.LeftA -> false
+  | _ -> true
+
+let create_assoc = function
+  | None -> Extend.RightA
+  | Some a -> a
+
+let error_level_assoc p current expected =
+  let open Pp in
+  let pr_assoc = function
+    | Extend.LeftA -> str "left"
+    | Extend.RightA -> str "right"
+    | Extend.NonA -> str "non" in
+  user_err 
+    (str "Level " ++ int p ++ str " is already declared " ++
+     pr_assoc current ++ str " associative while it is now expected to be " ++
+     pr_assoc expected ++ str " associative.")
+
+let create_pos = function
+  | None -> Extend.First
+  | Some lev -> Extend.After (constr_level lev)
+
+let find_position_gen current ensure assoc lev =
+  match lev with
+  | None ->
+      current, (None, None, None, None)
+  | Some n ->
+      let after = ref None in
+      let init = ref None in
+      let rec add_level q = function
+        | (p,_,_ as pa)::l when p > n -> pa :: add_level (Some p) l
+        | (p,a,reinit)::l when Int.equal p n ->
+            if reinit then
+	      let a' = create_assoc assoc in
+              (init := Some (a',create_pos q); (p,a',false)::l)
+	    else if admissible_assoc (a,assoc) then
+	      raise Exit
+            else
+	      error_level_assoc p a (Option.get assoc)
+	| l -> after := q; (n,create_assoc assoc,ensure)::l
+      in
+      try
+	let updated = add_level None current in
+	let assoc = create_assoc assoc in
+        begin match !init with
+        | None ->
+	  (* Create the entry *)
+	   updated, (Some (create_pos !after), Some assoc, Some (constr_level n), None)
+        | _ ->
+	  (* The reinit flag has been updated *)
+	   updated, (Some (Extend.Level (constr_level n)), None, None, !init)
+        end
+      with
+	  (* Nothing has changed *)
+          Exit ->
+	    (* Just inherit the existing associativity and name (None) *)
+	    current, (Some (Extend.Level (constr_level n)), None, None, None)
+
+let rec list_mem_assoc_triple x = function
+  | [] -> false
+  | (a,b,c) :: l -> Int.equal a x || list_mem_assoc_triple x l
+
+let register_empty_levels accu forpat levels =
+  let rec filter accu = function
+  | [] -> ([], accu)
+  | n :: rem ->
+    let rem, accu = filter accu rem in
+    let (clev, plev) = accu in
+    let levels = if forpat then plev else clev in
+    if not (list_mem_assoc_triple n levels) then
+      let nlev, ans = find_position_gen levels true None (Some n) in
+      let nlev = if forpat then (clev, nlev) else (nlev, plev) in
+      ans :: rem, nlev
+    else rem, accu
+  in
+  filter accu levels
+
+let find_position accu forpat assoc level =
+  let (clev, plev) = accu in
+  let levels = if forpat then plev else clev in
+  let nlev, ans = find_position_gen levels false assoc level in
+  let nlev = if forpat then (clev, nlev) else (nlev, plev) in
+  (ans, nlev)
+
+(**************************************************************************)
+(*
+ * --- Note on the mapping of grammar productions to camlp5 actions ---
+ *
+ * Translation of environments: a production
+ *   [ nt1(x1) ... nti(xi) ] -> act(x1..xi)
+ * is written (with camlp5 conventions):
+ *   (fun vi -> .... (fun v1 -> act(v1 .. vi) )..)
+ * where v1..vi are the values generated by non-terminals nt1..nti.
+ * Since the actions are executed by substituting an environment,
+ * the make_*_action family build the following closure:
+ *
+ *      ((fun env ->
+ *          (fun vi ->
+ *             (fun env -> ...
+ *
+ *                  (fun v1 ->
+ *                     (fun env -> gram_action .. env act)
+ *                     ((x1,v1)::env))
+ *                  ...)
+ *             ((xi,vi)::env)))
+ *         [])
+ *)
+
+(**********************************************************************)
+(** Declare Notations grammar rules                                   *)
+
+(**********************************************************************)
+(* Binding constr entry keys to entries                               *)
+
+(* Camlp5 levels do not treat NonA: use RightA with a NEXT on the left *)
+let camlp5_assoc = function
+  | Some NonA | Some RightA -> RightA
+  | None | Some LeftA -> LeftA
+
+let assoc_eq al ar = match al, ar with
+| NonA, NonA
+| RightA, RightA
+| LeftA, LeftA -> true
+| _, _ -> false
+
+(* [adjust_level assoc from prod] where [assoc] and [from] are the name
+   and associativity of the level where to add the rule; the meaning of
+   the result is
+
+     None = SELF
+     Some None = NEXT
+     Some (Some (n,cur)) = constr LEVEL n
+         s.t. if [cur] is set then [n] is the same as the [from] level *)
+let adjust_level assoc from = function
+(* Associativity is None means force the level *)
+  | (NumLevel n,BorderProd (_,None)) -> Some (Some (n,true))
+(* Compute production name on the right side *)
+  (* If NonA or LeftA on the right-hand side, set to NEXT *)
+  | (NumLevel n,BorderProd (Right,Some (NonA|LeftA))) ->
+      Some None
+  (* If RightA on the right-hand side, set to the explicit (current) level *)
+  | (NumLevel n,BorderProd (Right,Some RightA)) ->
+      Some (Some (n,true))
+(* Compute production name on the left side *)
+  (* If NonA on the left-hand side, adopt the current assoc ?? *)
+  | (NumLevel n,BorderProd (Left,Some NonA)) -> None
+  (* If the expected assoc is the current one, set to SELF *)
+  | (NumLevel n,BorderProd (Left,Some a)) when assoc_eq a (camlp5_assoc assoc) ->
+      None
+  (* Otherwise, force the level, n or n-1, according to expected assoc *)
+  | (NumLevel n,BorderProd (Left,Some a)) ->
+    begin match a with
+    | LeftA -> Some (Some (n, true))
+    | _ -> Some None
+    end
+  (* None means NEXT *)
+  | (NextLevel,_) -> Some None
+(* Compute production name elsewhere *)
+  | (NumLevel n,InternalProd) ->
+    if from = n + 1 then Some None else Some (Some (n, Int.equal n from))
+
+type _ target =
+| ForConstr : constr_expr target
+| ForPattern : cases_pattern_expr target
+
+type prod_info = production_level * production_position
+
+type (_, _) entry =
+| TTName : ('self, Misctypes.lname) entry
+| TTReference : ('self, reference) entry
+| TTBigint : ('self, Constrexpr.raw_natural_number) entry
+| TTConstr : prod_info * 'r target -> ('r, 'r) entry
+| TTConstrList : prod_info * Tok.t list * 'r target -> ('r, 'r list) entry
+| TTPattern : int -> ('self, cases_pattern_expr) entry
+| TTOpenBinderList : ('self, local_binder_expr list) entry
+| TTClosedBinderList : Tok.t list -> ('self, local_binder_expr list list) entry
+
+type _ any_entry = TTAny : ('s, 'r) entry -> 's any_entry
+
+(* This computes the name of the level where to add a new rule *)
+let interp_constr_entry_key : type r. r target -> int -> r Gram.entry * int option =
+  fun forpat level -> match forpat with
+  | ForConstr ->
+    if level = 200 then Constr.binder_constr, None
+    else Constr.operconstr, Some level
+  | ForPattern -> Constr.pattern, Some level
+
+let target_entry : type s. s target -> s Gram.entry = function
+| ForConstr -> Constr.operconstr
+| ForPattern -> Constr.pattern
+
+let is_self from e = match e with
+| (NumLevel n, BorderProd (Right, _ (* Some(NonA|LeftA) *))) -> false
+| (NumLevel n, BorderProd (Left, _)) -> Int.equal from n
+| _ -> false
+
+let is_binder_level from e = match e with
+| (NumLevel 200, (BorderProd (Right, _) | InternalProd)) -> from = 200
+| _ -> false
+
+let make_sep_rules = function
+  | [tk] -> Atoken tk
+  | tkl ->
+  let rec mkrule : Tok.t list -> string rules = function
+  | [] -> Rules ({ norec_rule = Stop }, fun _ -> (* dropped anyway: *) "")
+  | tkn :: rem ->
+    let Rules ({ norec_rule = r }, f) = mkrule rem in
+    let r = { norec_rule = Next (r, Atoken tkn) } in
+    Rules (r, fun _ -> f)
+  in
+  let r = mkrule (List.rev tkl) in
+  Arules [r]
+
+let symbol_of_target : type s. _ -> _ -> _ -> s target -> (s, s) symbol = fun p assoc from forpat ->
+  if is_binder_level from p then Aentryl (target_entry forpat, 200)
+  else if is_self from p then Aself
+  else
+    let g = target_entry forpat in
+    let lev = adjust_level assoc from p in
+    begin match lev with
+    | None -> Aentry g
+    | Some None -> Anext
+    | Some (Some (lev, cur)) -> Aentryl (g, lev)
+    end
+
+let symbol_of_entry : type s r. _ -> _ -> (s, r) entry -> (s, r) symbol = fun assoc from typ -> match typ with
+| TTConstr (p, forpat) -> symbol_of_target p assoc from forpat
+| TTConstrList (typ', [], forpat) ->
+  Alist1 (symbol_of_target typ' assoc from forpat)
+| TTConstrList (typ', tkl, forpat) ->
+  Alist1sep (symbol_of_target typ' assoc from forpat, make_sep_rules tkl)
+| TTPattern p -> Aentryl (Constr.pattern, p)
+| TTClosedBinderList [] -> Alist1 (Aentry Constr.binder)
+| TTClosedBinderList tkl -> Alist1sep (Aentry Constr.binder, make_sep_rules tkl)
+| TTName -> Aentry Prim.name
+| TTOpenBinderList -> Aentry Constr.open_binders
+| TTBigint -> Aentry Prim.bigint
+| TTReference -> Aentry Constr.global
+
+let interp_entry forpat e = match e with
+| ETProdName -> TTAny TTName
+| ETProdReference -> TTAny TTReference
+| ETProdBigint -> TTAny TTBigint
+| ETProdConstr p -> TTAny (TTConstr (p, forpat))
+| ETProdPattern p -> TTAny (TTPattern p)
+| ETProdOther _ -> assert false (** not used *)
+| ETProdConstrList (p, tkl) -> TTAny (TTConstrList (p, tkl, forpat))
+| ETProdBinderList ETBinderOpen -> TTAny TTOpenBinderList
+| ETProdBinderList (ETBinderClosed tkl) -> TTAny (TTClosedBinderList tkl)
+
+let cases_pattern_expr_of_name { CAst.loc; v = na } = CAst.make ?loc @@ match na with
+  | Anonymous -> CPatAtom None
+  | Name id   -> CPatAtom (Some (CAst.make ?loc @@ Ident id))
+
+type 'r env = {
+  constrs : 'r list;
+  constrlists : 'r list list;
+  binders : cases_pattern_expr list;
+  binderlists : local_binder_expr list list;
+}
+
+let push_constr subst v = { subst with constrs = v :: subst.constrs }
+
+let push_item : type s r. s target -> (s, r) entry -> s env -> r -> s env = fun forpat e subst v ->
+match e with
+| TTConstr _ -> push_constr subst v
+| TTName ->
+  begin match forpat with
+  | ForConstr -> { subst with binders = cases_pattern_expr_of_name v :: subst.binders }
+  | ForPattern -> push_constr subst (cases_pattern_expr_of_name v)
+  end
+| TTPattern _ ->
+  begin match forpat with
+  | ForConstr -> { subst with binders = v :: subst.binders }
+  | ForPattern -> push_constr subst v
+  end
+| TTOpenBinderList -> { subst with binderlists = v :: subst.binderlists }
+| TTClosedBinderList _ -> { subst with binderlists = List.flatten v :: subst.binderlists }
+| TTBigint ->
+  begin match forpat with
+  | ForConstr ->  push_constr subst (CAst.make @@ CPrim (Numeral (v,true)))
+  | ForPattern -> push_constr subst (CAst.make @@ CPatPrim (Numeral (v,true)))
+  end
+| TTReference ->
+  begin match forpat with
+  | ForConstr  -> push_constr subst (CAst.make @@ CRef (v, None))
+  | ForPattern -> push_constr subst (CAst.make @@ CPatAtom (Some v))
+  end
+| TTConstrList _ -> { subst with constrlists = v :: subst.constrlists }
+
+type (_, _) ty_symbol =
+| TyTerm : Tok.t -> ('s, string) ty_symbol
+| TyNonTerm : 's target * ('s, 'a) entry * ('s, 'a) symbol * bool -> ('s, 'a) ty_symbol
+
+type ('self, _, 'r) ty_rule =
+| TyStop : ('self, 'r, 'r) ty_rule
+| TyNext : ('self, 'a, 'r) ty_rule * ('self, 'b) ty_symbol -> ('self, 'b -> 'a, 'r) ty_rule
+| TyMark : int * bool * int * ('self, 'a, 'r) ty_rule -> ('self, 'a, 'r) ty_rule
+
+type 'r gen_eval = Loc.t -> 'r env -> 'r
+
+let rec ty_eval : type s a. (s, a, Loc.t -> s) ty_rule -> s gen_eval -> s env -> a = function
+| TyStop ->
+  fun f env loc -> f loc env
+| TyNext (rem, TyTerm _) ->
+  fun f env _ -> ty_eval rem f env
+| TyNext (rem, TyNonTerm (_, _, _, false)) ->
+  fun f env _ -> ty_eval rem f env
+| TyNext (rem, TyNonTerm (forpat, e, _, true)) ->
+  fun f env v ->
+    ty_eval rem f (push_item forpat e env v)
+| TyMark (n, b, p, rem) ->
+  fun f env ->
+    let heads, constrs = List.chop n env.constrs in
+    let constrlists, constrs =
+      if b then
+         (* We rearrange constrs = c1..cn rem and constrlists = [d1..dr e1..ep] rem' into
+            constrs = e1..ep rem and constrlists [c1..cn d1..dr] rem' *)
+         let constrlist = List.hd env.constrlists in
+         let constrlist, tail = List.chop (List.length constrlist - p) constrlist in
+         (heads @ constrlist) :: List.tl env.constrlists, tail @ constrs
+      else
+         (* We rearrange constrs = c1..cn e1..ep rem into
+            constrs = e1..ep rem and add a constr list [c1..cn] *)
+        let constrlist, tail = List.chop (n - p) heads in
+        constrlist :: env.constrlists, tail @ constrs
+    in
+    ty_eval rem f { env with constrs; constrlists; } 
+
+let rec ty_erase : type s a r. (s, a, r) ty_rule -> (s, a, r) Extend.rule = function
+| TyStop -> Stop
+| TyMark (_, _, _, r) -> ty_erase r
+| TyNext (rem, TyTerm tok) -> Next (ty_erase rem, Atoken tok)
+| TyNext (rem, TyNonTerm (_, _, s, _)) -> Next (ty_erase rem, s)
+
+type ('self, 'r) any_ty_rule =
+| AnyTyRule : ('self, 'act, Loc.t -> 'r) ty_rule -> ('self, 'r) any_ty_rule
+
+let make_ty_rule assoc from forpat prods =
+  let rec make_ty_rule = function
+  | [] -> AnyTyRule TyStop
+  | GramConstrTerminal tok :: rem ->
+    let AnyTyRule r = make_ty_rule rem in
+    AnyTyRule (TyNext (r, TyTerm tok))
+  | GramConstrNonTerminal (e, var) :: rem ->
+    let AnyTyRule r = make_ty_rule rem in
+    let TTAny e = interp_entry forpat e in
+    let s = symbol_of_entry assoc from e in
+    let bind = match var with None -> false | Some _ -> true in
+    AnyTyRule (TyNext (r, TyNonTerm (forpat, e, s, bind)))
+  | GramConstrListMark (n, b, p) :: rem ->
+    let AnyTyRule r = make_ty_rule rem in
+    AnyTyRule (TyMark (n, b, p, r))
+  in
+  make_ty_rule (List.rev prods)
+
+let target_to_bool : type r. r target -> bool = function
+| ForConstr -> false
+| ForPattern -> true
+
+let prepare_empty_levels forpat (pos,p4assoc,name,reinit) =
+  let empty = (pos, [(name, p4assoc, [])]) in
+  if forpat then ExtendRule (Constr.pattern, reinit, empty)
+  else ExtendRule (Constr.operconstr, reinit, empty)
+
+let rec pure_sublevels : type a b c. int option -> (a, b, c) rule -> int list = fun level r -> match r with
+| Stop -> []
+| Next (rem, Aentryl (_, i)) ->
+  let rem = pure_sublevels level rem in
+  begin match level with
+  | Some j when Int.equal i j -> rem
+  | _ -> i :: rem
+  end
+| Next (rem, _) -> pure_sublevels level rem
+
+let make_act : type r. r target -> _ -> r gen_eval = function
+| ForConstr -> fun notation loc env ->
+  let env = (env.constrs, env.constrlists, env.binders, env.binderlists) in
+  CAst.make ~loc @@ CNotation (notation, env)
+| ForPattern -> fun notation loc env ->
+  let env = (env.constrs, env.constrlists) in
+  CAst.make ~loc @@ CPatNotation (notation, env, [])
+
+let extend_constr state forpat ng =
+  let n,_,_ = ng.notgram_level in
+  let assoc = ng.notgram_assoc in
+  let (entry, level) = interp_constr_entry_key forpat n in
+  let fold (accu, state) pt =
+    let AnyTyRule r = make_ty_rule assoc n forpat pt in
+    let symbs = ty_erase r in
+    let pure_sublevels = pure_sublevels level symbs in
+    let isforpat = target_to_bool forpat in
+    let needed_levels, state = register_empty_levels state isforpat pure_sublevels in
+    let (pos,p4assoc,name,reinit), state = find_position state isforpat assoc level in
+    let empty_rules = List.map (prepare_empty_levels isforpat) needed_levels in
+    let empty = { constrs = []; constrlists = []; binders = []; binderlists = [] } in
+    let act = ty_eval r (make_act forpat ng.notgram_notation) empty in
+    let rule = (name, p4assoc, [Rule (symbs, act)]) in
+    let r = ExtendRule (entry, reinit, (pos, [rule])) in
+    (accu @ empty_rules @ [r], state)
+  in
+  List.fold_left fold ([], state) ng.notgram_prods
+
+let constr_levels = GramState.field ()
+
+let extend_constr_notation ng state =
+  let levels = match GramState.get state constr_levels with
+  | None -> default_constr_levels
+  | Some lev -> lev
+  in
+  (* Add the notation in constr *)
+  let (r, levels) = extend_constr levels ForConstr ng in
+  (* Add the notation in cases_pattern *)
+  let (r', levels) = extend_constr levels ForPattern ng in
+  let state = GramState.set state constr_levels levels in
+  (r @ r', state)
+
+let constr_grammar : one_notation_grammar grammar_command =
+  create_grammar_command "Notation" extend_constr_notation
+
+let extend_constr_grammar ntn = extend_grammar_command constr_grammar ntn
diff --git a/vernac/egramcoq.mli b/vernac/egramcoq.mli
new file mode 100644
index 000000000..e15add10f
--- /dev/null
+++ b/vernac/egramcoq.mli
@@ -0,0 +1,19 @@
+(************************************************************************)
+(*         *   The Coq Proof Assistant / The Coq Development Team       *)
+(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2018       *)
+(* <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)         *)
+(************************************************************************)
+
+(** Mapping of grammar productions to camlp5 actions *)
+
+(** This is the part specific to Coq-level Notation and Tactic Notation.
+    For the ML-level tactic and vernac extensions, see Egramml. *)
+
+(** {5 Adding notations} *)
+
+val extend_constr_grammar : Notation_term.one_notation_grammar -> unit
+(** Add a term notation rule to the parsing system. *)
diff --git a/vernac/egramml.ml b/vernac/egramml.ml
new file mode 100644
index 000000000..90cd7d10b
--- /dev/null
+++ b/vernac/egramml.ml
@@ -0,0 +1,84 @@
+(************************************************************************)
+(*         *   The Coq Proof Assistant / The Coq Development Team       *)
+(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2018       *)
+(* <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 Util
+open Extend
+open Pcoq
+open Genarg
+open Vernacexpr
+
+(** Grammar extensions declared at ML level *)
+
+type 's grammar_prod_item =
+  | GramTerminal of string
+  | GramNonTerminal :
+      ('a raw_abstract_argument_type option * ('s, 'a) symbol) Loc.located -> 's grammar_prod_item
+
+type 'a ty_arg = ('a -> raw_generic_argument)
+
+type ('self, _, 'r) ty_rule =
+| TyStop : ('self, 'r, 'r) ty_rule
+| TyNext : ('self, 'a, 'r) ty_rule * ('self, 'b) Extend.symbol * 'b ty_arg option ->
+  ('self, 'b -> 'a, 'r) ty_rule
+
+type ('self, 'r) any_ty_rule =
+| AnyTyRule : ('self, 'act, Loc.t -> 'r) ty_rule -> ('self, 'r) any_ty_rule
+
+let rec ty_rule_of_gram = function
+| [] -> AnyTyRule TyStop
+| GramTerminal s :: rem ->
+  let AnyTyRule rem = ty_rule_of_gram rem in
+  let tok = Atoken (CLexer.terminal s) in
+  let r = TyNext (rem, tok, None) in
+  AnyTyRule r
+| GramNonTerminal (_, (t, tok)) :: rem ->
+  let AnyTyRule rem = ty_rule_of_gram rem in
+  let inj = Option.map (fun t obj -> Genarg.in_gen t obj) t in
+  let r = TyNext (rem, tok, inj) in
+  AnyTyRule r
+
+let rec ty_erase : type s a r. (s, a, r) ty_rule -> (s, a, r) Extend.rule = function
+| TyStop -> Extend.Stop
+| TyNext (rem, tok, _) -> Extend.Next (ty_erase rem, tok)
+
+type 'r gen_eval = Loc.t -> raw_generic_argument list -> 'r
+
+let rec ty_eval : type s a. (s, a, Loc.t -> s) ty_rule -> s gen_eval -> a = function
+| TyStop -> fun f loc -> f loc []
+| TyNext (rem, tok, None) -> fun f _ -> ty_eval rem f
+| TyNext (rem, tok, Some inj) -> fun f x ->
+  let f loc args = f loc (inj x :: args) in
+  ty_eval rem f
+
+let make_rule f prod =
+  let AnyTyRule ty_rule = ty_rule_of_gram (List.rev prod) in
+  let symb = ty_erase ty_rule in
+  let f loc l = f loc (List.rev l) in
+  let act = ty_eval ty_rule f in
+  Extend.Rule (symb, act)
+
+(** Vernac grammar extensions *)
+
+let vernac_exts = ref []
+
+let get_extend_vernac_rule (s, i) =
+  try
+    let find ((name, j), _) = String.equal name s && Int.equal i j in
+    let (_, rules) = List.find find !vernac_exts in
+    rules
+  with
+  | Failure _ -> raise Not_found
+
+let extend_vernac_command_grammar s nt gl =
+  let nt = Option.default Vernac_.command nt in
+  vernac_exts := (s,gl) :: !vernac_exts;
+  let mkact loc l = VernacExtend (s, l) in
+  let rules = [make_rule mkact gl] in
+  grammar_extend nt None (None, [None, None, rules])
diff --git a/vernac/egramml.mli b/vernac/egramml.mli
new file mode 100644
index 000000000..31aa1a989
--- /dev/null
+++ b/vernac/egramml.mli
@@ -0,0 +1,33 @@
+(************************************************************************)
+(*         *   The Coq Proof Assistant / The Coq Development Team       *)
+(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2018       *)
+(* <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 Vernacexpr
+
+(** Mapping of grammar productions to camlp5 actions. *)
+
+(** This is the part specific to vernac extensions.
+    For the Coq-level Notation and Tactic Notation, see Egramcoq. *)
+
+type 's grammar_prod_item =
+  | GramTerminal of string
+  | GramNonTerminal : ('a Genarg.raw_abstract_argument_type option *
+      ('s, 'a) Extend.symbol) Loc.located -> 's grammar_prod_item
+
+val extend_vernac_command_grammar :
+  Vernacexpr.extend_name -> vernac_expr Pcoq.Gram.entry option ->
+    vernac_expr grammar_prod_item list -> unit
+
+val get_extend_vernac_rule : Vernacexpr.extend_name -> vernac_expr grammar_prod_item list
+
+(** Utility function reused in Egramcoq : *)
+
+val make_rule :
+  (Loc.t -> Genarg.raw_generic_argument list -> 'a) ->
+  'a grammar_prod_item list -> 'a Extend.production_rule
diff --git a/vernac/ppvernac.ml b/vernac/ppvernac.ml
new file mode 100644
index 000000000..7a34e8027
--- /dev/null
+++ b/vernac/ppvernac.ml
@@ -0,0 +1,1219 @@
+(************************************************************************)
+(*         *   The Coq Proof Assistant / The Coq Development Team       *)
+(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2018       *)
+(* <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 Pp
+open Names
+
+open CErrors
+open Util
+open CAst
+
+open Extend
+open Libnames
+open Decl_kinds
+open Constrexpr
+open Constrexpr_ops
+open Vernacexpr
+open Declaremods
+open Pputils
+
+  open Ppconstr
+
+  let do_not_tag _ x = x
+  let tag_keyword = do_not_tag ()
+  let tag_vernac  = do_not_tag
+
+  let keyword s = tag_keyword (str s)
+
+  let pr_constr = pr_constr_expr
+  let pr_lconstr = pr_lconstr_expr
+  let pr_spc_lconstr = pr_sep_com spc pr_lconstr_expr
+
+  let pr_uconstraint (l, d, r) =
+    pr_glob_level l ++ spc () ++ Univ.pr_constraint_type d ++ spc () ++
+      pr_glob_level r
+
+  let pr_univ_name_list = function
+    | None -> mt ()
+    | Some l ->
+      str "@{" ++ prlist_with_sep spc pr_lname l ++ str"}"
+
+  let pr_univdecl_instance l extensible =
+    prlist_with_sep spc pr_lident l ++
+    (if extensible then str"+" else mt ())
+
+  let pr_univdecl_constraints l extensible =
+    if List.is_empty l && extensible then mt ()
+    else str"|" ++ spc () ++ prlist_with_sep (fun () -> str",") pr_uconstraint l ++
+           (if extensible then str"+" else mt())
+
+  let pr_universe_decl l =
+    let open Misctypes in
+    match l with
+    | None -> mt ()
+    | Some l ->
+      str"@{" ++ pr_univdecl_instance l.univdecl_instance l.univdecl_extensible_instance ++
+        pr_univdecl_constraints l.univdecl_constraints l.univdecl_extensible_constraints ++ str "}"
+
+  let pr_ident_decl (lid, l) =
+    pr_lident lid ++ pr_universe_decl l
+
+  let string_of_fqid fqid =
+    String.concat "." (List.map Id.to_string fqid)
+
+  let pr_fqid fqid = str (string_of_fqid fqid)
+
+  let pr_lfqid {CAst.loc;v=fqid} =
+    match loc with
+    | None     -> pr_fqid fqid
+    | Some loc -> let (b,_) = Loc.unloc loc in
+                  pr_located pr_fqid @@ Loc.tag ~loc:(Loc.make_loc (b,b + String.length (string_of_fqid fqid))) fqid
+
+  let pr_lname_decl (n, u) =
+    pr_lname n ++ pr_universe_decl u
+
+  let pr_smart_global = Pputils.pr_or_by_notation pr_reference
+
+  let pr_ltac_ref = Libnames.pr_reference
+
+  let pr_module = Libnames.pr_reference
+
+  let pr_import_module = Libnames.pr_reference
+
+  let sep_end = function
+    | VernacBullet _
+    | VernacSubproof _
+    | VernacEndSubproof -> str""
+    | _ -> str"."
+
+  let pr_gen t = Pputils.pr_raw_generic (Global.env ()) t
+
+  let sep = fun _ -> spc()
+  let sep_v2 = fun _ -> str"," ++ spc()
+
+  let pr_at_level = function
+    | NumLevel n -> keyword "at" ++ spc () ++ keyword "level" ++ spc () ++ int n
+    | NextLevel -> keyword "at" ++ spc () ++ keyword "next" ++ spc () ++ keyword "level"
+
+  let pr_constr_as_binder_kind = function
+    | AsIdent -> keyword "as ident"
+    | AsIdentOrPattern -> keyword "as pattern"
+    | AsStrictPattern -> keyword "as strict pattern"
+
+  let pr_strict b = if b then str "strict " else mt ()
+
+  let pr_set_entry_type pr = function
+    | ETName -> str"ident"
+    | ETReference -> str"global"
+    | ETPattern (b,None) -> pr_strict b ++ str"pattern"
+    | ETPattern (b,Some n) -> pr_strict b ++ str"pattern" ++ spc () ++ pr_at_level (NumLevel n)
+    | ETConstr lev -> str"constr" ++ pr lev
+    | ETOther (_,e) -> str e
+    | ETConstrAsBinder (bk,lev) -> pr lev ++ spc () ++ pr_constr_as_binder_kind bk
+    | ETBigint -> str "bigint"
+    | ETBinder true -> str "binder"
+    | ETBinder false -> str "closed binder"
+
+  let pr_at_level_opt = function
+    | None -> mt ()
+    | Some n -> spc () ++ pr_at_level n
+
+  let pr_set_simple_entry_type =
+    pr_set_entry_type pr_at_level_opt
+
+  let pr_comment pr_c = function
+    | CommentConstr c -> pr_c c
+    | CommentString s -> qs s
+    | CommentInt n -> int n
+
+  let pr_in_out_modules = function
+    | SearchInside l -> spc() ++ keyword "inside" ++ spc() ++ prlist_with_sep sep pr_module l
+    | SearchOutside [] -> mt()
+    | SearchOutside l -> spc() ++ keyword "outside" ++ spc() ++ prlist_with_sep sep pr_module l
+
+  let pr_search_about (b,c) =
+    (if b then str "-" else mt()) ++
+      match c with
+        | SearchSubPattern p -> pr_constr_pattern_expr p
+        | SearchString (s,sc) -> qs s ++ pr_opt (fun sc -> str "%" ++ str sc) sc
+
+  let pr_search a gopt b pr_p =
+    pr_opt (fun g -> Goal_select.pr_goal_selector g ++ str ":"++ spc()) gopt
+    ++
+      match a with
+      | SearchHead c -> keyword "SearchHead" ++ spc() ++ pr_p c ++ pr_in_out_modules b
+      | SearchPattern c -> keyword "SearchPattern" ++ spc() ++ pr_p c ++ pr_in_out_modules b
+      | SearchRewrite c -> keyword "SearchRewrite" ++ spc() ++ pr_p c ++ pr_in_out_modules b
+      | SearchAbout sl ->
+	 keyword "Search" ++ spc() ++ prlist_with_sep spc pr_search_about sl ++ pr_in_out_modules b
+
+  let pr_locality local = if local then keyword "Local" else keyword "Global"
+
+  let pr_option_ref_value = function
+    | QualidRefValue id -> pr_reference id
+    | StringRefValue s -> qs s
+
+  let pr_printoption table b =
+    prlist_with_sep spc str table ++
+      pr_opt (prlist_with_sep sep pr_option_ref_value) b
+
+  let pr_set_option a b =
+    let pr_opt_value = function
+      | IntValue None -> assert false
+    (* This should not happen because of the grammar *)
+      | IntValue (Some n) -> spc() ++ int n
+      | StringValue s -> spc() ++ str s
+      | StringOptValue None -> mt()
+      | StringOptValue (Some s) -> spc() ++ str s
+      | BoolValue b -> mt()
+    in pr_printoption a None ++ pr_opt_value b
+
+  let pr_opt_hintbases l = match l with
+    | [] -> mt()
+    | _ as z -> str":" ++ spc() ++ prlist_with_sep sep str z
+
+  let pr_reference_or_constr pr_c = function
+    | HintsReference r -> pr_reference r
+    | HintsConstr c -> pr_c c
+
+  let pr_hint_mode = function
+    | ModeInput -> str"+"
+    | ModeNoHeadEvar -> str"!"
+    | ModeOutput -> str"-"
+
+  let pr_hint_info pr_pat { Typeclasses.hint_priority = pri; hint_pattern = pat } =
+    pr_opt (fun x -> str"|" ++ int x) pri ++
+    pr_opt (fun y -> (if Option.is_empty pri then str"| " else mt()) ++ pr_pat y) pat
+
+  let pr_hints db h pr_c pr_pat =
+    let opth = pr_opt_hintbases db  in
+    let pph =
+      match h with
+        | HintsResolve l ->
+          keyword "Resolve " ++ prlist_with_sep sep
+            (fun (info, _, c) -> pr_reference_or_constr pr_c c ++ pr_hint_info pr_pat info)
+            l
+        | HintsImmediate l ->
+          keyword "Immediate" ++ spc() ++
+            prlist_with_sep sep (fun c -> pr_reference_or_constr pr_c c) l
+        | HintsUnfold l ->
+          keyword "Unfold" ++ spc () ++ prlist_with_sep sep pr_reference l
+        | HintsTransparency (l, b) ->
+          keyword (if b then "Transparent" else "Opaque")
+          ++ spc ()
+          ++ prlist_with_sep sep pr_reference l
+        | HintsMode (m, l) ->
+          keyword "Mode"
+          ++ spc ()
+          ++ pr_reference m ++ spc() ++
+            prlist_with_sep spc pr_hint_mode l
+        | HintsConstructors c ->
+          keyword "Constructors"
+          ++ spc() ++ prlist_with_sep spc pr_reference c
+        | HintsExtern (n,c,tac) ->
+          let pat = match c with None -> mt () | Some pat -> pr_pat pat in
+          keyword "Extern" ++ spc() ++ int n ++ spc() ++ pat ++ str" =>" ++
+            spc() ++ Pputils.pr_raw_generic (Global.env ()) tac
+    in
+    hov 2 (keyword "Hint "++ pph ++ opth)
+
+  let pr_with_declaration pr_c = function
+    | CWith_Definition (id,udecl,c) ->
+      let p = pr_c c in
+      keyword "Definition" ++ spc() ++ pr_lfqid id ++ pr_universe_decl udecl ++ str" := " ++ p
+    | CWith_Module (id,qid) ->
+      keyword "Module" ++ spc() ++ pr_lfqid id ++ str" := " ++
+        pr_ast pr_qualid qid
+
+  let rec pr_module_ast leading_space pr_c = function
+    | { loc ; v = CMident qid } ->
+      if leading_space then
+        spc () ++ pr_located pr_qualid (loc, qid)
+      else
+        pr_located pr_qualid (loc,qid)
+    | { v = CMwith (mty,decl) } ->
+      let m = pr_module_ast leading_space pr_c mty in
+      let p = pr_with_declaration pr_c decl in
+      m ++ spc() ++ keyword "with" ++ spc() ++ p
+    | { v = CMapply (me1, ( { v = CMident _ } as me2 ) ) } ->
+      pr_module_ast leading_space pr_c me1 ++ spc() ++ pr_module_ast false pr_c me2
+    | { v = CMapply (me1,me2) } ->
+      pr_module_ast leading_space pr_c me1 ++ spc() ++
+        hov 1 (str"(" ++ pr_module_ast false pr_c me2 ++ str")")
+
+  let pr_inline = function
+    | DefaultInline -> mt ()
+    | NoInline -> str "[no inline]"
+    | InlineAt i -> str "[inline at level " ++ int i ++ str "]"
+
+  let pr_assumption_inline = function
+    | DefaultInline -> str "Inline"
+    | NoInline -> mt ()
+    | InlineAt i -> str "Inline(" ++ int i ++ str ")"
+
+  let pr_module_ast_inl leading_space pr_c (mast,inl) =
+    pr_module_ast leading_space pr_c mast ++ pr_inline inl
+
+  let pr_of_module_type prc = function
+    | Enforce mty -> str ":" ++ pr_module_ast_inl true prc mty
+    | Check mtys ->
+      prlist_strict (fun m -> str "<:" ++ pr_module_ast_inl true prc m) mtys
+
+  let pr_require_token = function
+    | Some true ->
+      keyword "Export" ++ spc ()
+    | Some false ->
+      keyword "Import" ++ spc ()
+    | None -> mt()
+
+  let pr_module_vardecls pr_c (export,idl,(mty,inl)) =
+    let m = pr_module_ast true pr_c mty in
+    spc() ++
+      hov 1 (str"(" ++ pr_require_token export ++
+               prlist_with_sep spc pr_lident idl ++ str":" ++ m ++ str")")
+
+  let pr_module_binders l pr_c =
+    prlist_strict (pr_module_vardecls pr_c) l
+
+  let pr_type_option pr_c = function
+    | { v = CHole (k, Misctypes.IntroAnonymous, _) } -> mt()
+    | _ as c -> brk(0,2) ++ str" :" ++ pr_c c
+
+  let pr_decl_notation prc ({loc; v=ntn},c,scopt) =
+    fnl () ++ keyword "where " ++ qs ntn ++ str " := "
+    ++ Flags.without_option Flags.beautify prc c ++
+      pr_opt (fun sc -> str ": " ++ str sc) scopt
+
+  let pr_binders_arg =
+    pr_non_empty_arg pr_binders
+
+  let pr_and_type_binders_arg bl =
+    pr_binders_arg bl
+
+  let pr_onescheme (idop,schem) =
+    match schem with
+      | InductionScheme (dep,ind,s) ->
+        (match idop with
+          | Some id -> hov 0 (pr_lident id ++ str" :=") ++ spc()
+          | None -> spc ()
+        ) ++
+          hov 0 ((if dep then keyword "Induction for" else keyword "Minimality for")
+                 ++ spc() ++ pr_smart_global ind) ++ spc() ++
+          hov 0 (keyword "Sort" ++ spc() ++ Termops.pr_sort_family s)
+      | CaseScheme (dep,ind,s) ->
+        (match idop with
+          | Some id -> hov 0 (pr_lident id ++ str" :=") ++ spc()
+          | None -> spc ()
+        ) ++
+          hov 0 ((if dep then keyword "Elimination for" else keyword "Case for")
+                 ++ spc() ++ pr_smart_global ind) ++ spc() ++
+          hov 0 (keyword "Sort" ++ spc() ++ Termops.pr_sort_family s)
+      | EqualityScheme ind ->
+        (match idop with
+          | Some id -> hov 0 (pr_lident id ++ str" :=") ++ spc()
+          | None -> spc()
+        ) ++
+          hov 0 (keyword "Equality for")
+        ++ spc() ++ pr_smart_global ind
+
+  let begin_of_inductive = function
+    | [] -> 0
+    | (_,({loc},_))::_ -> Option.cata (fun loc -> fst (Loc.unloc loc)) 0 loc
+
+  let pr_class_rawexpr = function
+    | FunClass -> keyword "Funclass"
+    | SortClass -> keyword "Sortclass"
+    | RefClass qid -> pr_smart_global qid
+
+  let pr_assumption_token many discharge kind =
+    match discharge, kind with
+      | (NoDischarge,Logical) ->
+        keyword (if many then "Axioms" else "Axiom")
+      | (NoDischarge,Definitional) ->
+        keyword (if many then "Parameters" else "Parameter")
+      | (NoDischarge,Conjectural) -> str"Conjecture"
+      | (DoDischarge,Logical) ->
+        keyword (if many then "Hypotheses" else "Hypothesis")
+      | (DoDischarge,Definitional) ->
+        keyword (if many then "Variables" else "Variable")
+      | (DoDischarge,Conjectural) ->
+        anomaly (Pp.str "Don't know how to beautify a local conjecture.")
+
+  let pr_params pr_c (xl,(c,t)) =
+    hov 2 (prlist_with_sep sep pr_lident xl ++ spc() ++
+             (if c then str":>" else str":" ++
+                 spc() ++ pr_c t))
+
+  let rec factorize = function
+    | [] -> []
+    | (c,(idl,t))::l ->
+      match factorize l with
+        | (xl,((c', t') as r))::l'
+            when (c : bool) == c' && Pervasives.(=) t t' ->
+          (** FIXME: we need equality on constr_expr *)
+          (idl@xl,r)::l'
+        | l' -> (idl,(c,t))::l'
+
+  let pr_ne_params_list pr_c l =
+    match factorize l with
+      | [p] -> pr_params pr_c p
+      | l ->
+        prlist_with_sep spc
+          (fun p -> hov 1 (str "(" ++ pr_params pr_c p ++ str ")")) l
+
+(*
+  prlist_with_sep pr_semicolon (pr_params pr_c)
+*)
+
+  let pr_thm_token k = keyword (Kindops.string_of_theorem_kind k)
+
+  let pr_syntax_modifier = function
+    | SetItemLevel (l,n) ->
+      prlist_with_sep sep_v2 str l ++ spc () ++ pr_at_level n
+    | SetItemLevelAsBinder (l,bk,n) ->
+      prlist_with_sep sep_v2 str l ++
+      spc() ++ pr_at_level_opt n ++ spc() ++ pr_constr_as_binder_kind bk
+    | SetLevel n -> pr_at_level (NumLevel n)
+    | SetAssoc LeftA -> keyword "left associativity"
+    | SetAssoc RightA -> keyword "right associativity"
+    | SetAssoc NonA -> keyword "no associativity"
+    | SetEntryType (x,typ) -> str x ++ spc() ++ pr_set_simple_entry_type typ
+    | SetOnlyPrinting -> keyword "only printing"
+    | SetOnlyParsing -> keyword "only parsing"
+    | SetCompatVersion v -> keyword("compat \"" ^ Flags.pr_version v ^ "\"")
+    | SetFormat("text",s) -> keyword "format " ++ pr_ast qs s
+    | SetFormat(k,s) -> keyword "format " ++ qs k ++ spc() ++ pr_ast qs s
+
+  let pr_syntax_modifiers = function
+    | [] -> mt()
+    | l -> spc() ++
+      hov 1 (str"(" ++ prlist_with_sep sep_v2 pr_syntax_modifier l ++ str")")
+
+  let pr_rec_definition ((iddecl,ro,bl,type_,def),ntn) =
+    let pr_pure_lconstr c = Flags.without_option Flags.beautify pr_lconstr c in
+    let annot = pr_guard_annot pr_lconstr_expr bl ro in
+    pr_ident_decl iddecl ++ pr_binders_arg bl ++ annot
+    ++ pr_type_option (fun c -> spc() ++ pr_lconstr_expr c) type_
+    ++ pr_opt (fun def -> str":=" ++ brk(1,2) ++ pr_pure_lconstr def) def
+    ++ prlist (pr_decl_notation pr_constr) ntn
+
+  let pr_statement head (idpl,(bl,c)) =
+    hov 2
+      (head ++ spc() ++ pr_ident_decl idpl ++ spc() ++
+         (match bl with [] -> mt() | _ -> pr_binders bl ++ spc()) ++
+         str":" ++ pr_spc_lconstr c)
+
+(**************************************)
+(* Pretty printer for vernac commands *)
+(**************************************)
+
+  let pr_constrarg c = spc () ++ pr_constr c
+  let pr_lconstrarg c = spc () ++ pr_lconstr c
+  let pr_intarg n = spc () ++ int n
+
+  let pr_oc = function
+    | None -> str" :"
+    | Some true -> str" :>"
+    | Some false -> str" :>>"
+
+  let pr_record_field ((x, pri), ntn) =
+    let prx = match x with
+      | (oc,AssumExpr (id,t)) ->
+        hov 1 (pr_lname id ++
+                 pr_oc oc ++ spc() ++
+                 pr_lconstr_expr t)
+      | (oc,DefExpr(id,b,opt)) -> (match opt with
+          | Some t ->
+            hov 1 (pr_lname id ++
+                     pr_oc oc ++ spc() ++
+                     pr_lconstr_expr t ++ str" :=" ++ pr_lconstr b)
+          | None ->
+            hov 1 (pr_lname id ++ str" :=" ++ spc() ++
+                     pr_lconstr b)) in
+    let prpri = match pri with None -> mt() | Some i -> str "| " ++ int i in
+    prx ++ prpri ++ prlist (pr_decl_notation pr_constr) ntn
+
+  let pr_record_decl b c fs =
+    pr_opt pr_lident c ++ (if c = None then str"{" else str" {") ++
+      hv 0 (prlist_with_sep pr_semicolon pr_record_field fs ++ str"}")
+
+  let pr_printable = function
+    | PrintFullContext ->
+      keyword "Print All"
+    | PrintSectionContext s ->
+      keyword "Print Section" ++ spc() ++ Libnames.pr_reference s
+    | PrintGrammar ent ->
+      keyword "Print Grammar" ++ spc() ++ str ent
+    | PrintLoadPath dir ->
+      keyword "Print LoadPath" ++ pr_opt DirPath.print dir
+    | PrintModules ->
+      keyword "Print Modules"
+    | PrintMLLoadPath ->
+      keyword "Print ML Path"
+    | PrintMLModules ->
+      keyword "Print ML Modules"
+    | PrintDebugGC ->
+      keyword "Print ML GC"
+    | PrintGraph ->
+      keyword "Print Graph"
+    | PrintClasses ->
+      keyword "Print Classes"
+    | PrintTypeClasses ->
+      keyword "Print TypeClasses"
+    | PrintInstances qid ->
+      keyword "Print Instances" ++ spc () ++ pr_smart_global qid
+    | PrintCoercions ->
+      keyword "Print Coercions"
+    | PrintCoercionPaths (s,t) ->
+      keyword "Print Coercion Paths" ++ spc()
+      ++ pr_class_rawexpr s ++ spc()
+      ++ pr_class_rawexpr t
+    | PrintCanonicalConversions ->
+      keyword "Print Canonical Structures"
+    | PrintTables ->
+      keyword "Print Tables"
+    | PrintHintGoal ->
+      keyword "Print Hint"
+    | PrintHint qid ->
+      keyword "Print Hint" ++ spc () ++ pr_smart_global qid
+    | PrintHintDb ->
+      keyword "Print Hint *"
+    | PrintHintDbName s ->
+      keyword "Print HintDb" ++ spc () ++ str s
+    | PrintUniverses (b, fopt) ->
+      let cmd =
+        if b then "Print Sorted Universes"
+        else "Print Universes"
+      in
+      keyword cmd ++ pr_opt str fopt
+    | PrintName (qid,udecl) ->
+      keyword "Print" ++ spc()  ++ pr_smart_global qid ++ pr_univ_name_list udecl
+    | PrintModuleType qid ->
+      keyword "Print Module Type" ++ spc() ++ pr_reference qid
+    | PrintModule qid ->
+      keyword "Print Module" ++ spc() ++ pr_reference qid
+    | PrintInspect n ->
+      keyword "Inspect" ++ spc() ++ int n
+    | PrintScopes ->
+      keyword "Print Scopes"
+    | PrintScope s ->
+      keyword "Print Scope" ++ spc() ++ str s
+    | PrintVisibility s ->
+      keyword "Print Visibility" ++ pr_opt str s
+    | PrintAbout (qid,l,gopt) ->
+       pr_opt (fun g -> Goal_select.pr_goal_selector g ++ str ":"++ spc()) gopt
+       ++ keyword "About" ++ spc()  ++ pr_smart_global qid ++ pr_univ_name_list l
+    | PrintImplicit qid ->
+      keyword "Print Implicit" ++ spc()  ++ pr_smart_global qid
+    (* spiwack: command printing all the axioms and section variables used in a
+       term *)
+    | PrintAssumptions (b, t, qid) ->
+      let cmd = match b, t with
+        | true, true -> "Print All Dependencies"
+        | true, false -> "Print Opaque Dependencies"
+        | false, true -> "Print Transparent Dependencies"
+        | false, false -> "Print Assumptions"
+      in
+      keyword cmd ++ spc() ++ pr_smart_global qid
+    | PrintNamespace dp ->
+      keyword "Print Namespace" ++ DirPath.print dp
+    | PrintStrategy None ->
+      keyword "Print Strategies"
+    | PrintStrategy (Some qid) ->
+      keyword "Print Strategy" ++ pr_smart_global qid
+
+  let pr_using e =
+    let rec aux = function
+      | SsEmpty -> "()"
+      | SsType -> "(Type)"
+      | SsSingl { v=id } -> "("^Id.to_string id^")"
+      | SsCompl e -> "-" ^ aux e^""
+      | SsUnion(e1,e2) -> "("^aux e1 ^" + "^ aux e2^")"
+      | SsSubstr(e1,e2) -> "("^aux e1 ^" - "^ aux e2^")"
+      | SsFwdClose e -> "("^aux e^")*"
+    in Pp.str (aux e)
+
+  let pr_extend s cl =
+    let pr_arg a =
+      try pr_gen a
+      with Failure _ -> str "<error in " ++ str (fst s) ++ str ">" in
+    try
+      let rl = Egramml.get_extend_vernac_rule s in
+      let rec aux rl cl =
+        match rl, cl with
+        | Egramml.GramNonTerminal _ :: rl, arg :: cl -> pr_arg arg :: aux rl cl
+        | Egramml.GramTerminal s :: rl, cl -> str s :: aux rl cl
+        | [], [] -> []
+        | _ -> assert false in
+      hov 1 (pr_sequence identity (aux rl cl))
+    with Not_found ->
+      hov 1 (str "TODO(" ++ str (fst s) ++ spc () ++ prlist_with_sep sep pr_arg cl ++ str ")")
+
+  let pr_vernac_expr v =
+    let return = tag_vernac v in
+    match v with
+      | VernacLoad (f,s) ->
+        return (
+          keyword "Load"
+          ++ if f then
+              (spc() ++ keyword "Verbose" ++ spc())
+            else
+              spc() ++ qs s
+        )
+
+      (* Proof management *)
+      | VernacAbortAll ->
+        return (keyword "Abort All")
+      | VernacRestart ->
+        return (keyword "Restart")
+      | VernacUnfocus ->
+        return (keyword "Unfocus")
+      | VernacUnfocused ->
+        return (keyword "Unfocused")
+      | VernacAbort id ->
+        return (keyword "Abort" ++ pr_opt pr_lident id)
+      | VernacUndo i ->
+        return (
+          if Int.equal i 1 then keyword "Undo" else keyword "Undo" ++ pr_intarg i
+        )
+      | VernacUndoTo i ->
+        return (keyword "Undo" ++ spc() ++ keyword "To" ++ pr_intarg i)
+      | VernacFocus i ->
+        return (keyword "Focus" ++ pr_opt int i)
+      | VernacShow s ->
+        let pr_goal_reference = function
+          | OpenSubgoals -> mt ()
+          | NthGoal n -> spc () ++ int n
+          | GoalId id -> spc () ++ pr_id id
+        in
+        let pr_showable = function
+          | ShowGoal n -> keyword "Show" ++ pr_goal_reference n
+          | ShowProof -> keyword "Show Proof"
+          | ShowScript -> keyword "Show Script"
+          | ShowExistentials -> keyword "Show Existentials"
+          | ShowUniverses -> keyword "Show Universes"
+          | ShowProofNames -> keyword "Show Conjectures"
+          | ShowIntros b -> keyword "Show " ++ (if b then keyword "Intros" else keyword "Intro")
+          | ShowMatch id -> keyword "Show Match " ++ pr_reference id
+        in
+        return (pr_showable s)
+      | VernacCheckGuard ->
+        return (keyword "Guarded")
+
+    (* Resetting *)
+      | VernacResetName id ->
+        return (keyword "Reset" ++ spc() ++ pr_lident id)
+      | VernacResetInitial ->
+        return (keyword "Reset Initial")
+      | VernacBack i ->
+        return (
+          if Int.equal i 1 then keyword "Back" else keyword "Back" ++ pr_intarg i
+        )
+      | VernacBackTo i ->
+        return (keyword "BackTo" ++ pr_intarg i)
+
+    (* State management *)
+      | VernacWriteState s ->
+        return (keyword "Write State" ++ spc () ++ qs s)
+      | VernacRestoreState s ->
+        return  (keyword "Restore State" ++ spc() ++ qs s)
+
+    (* Syntax *)
+      | VernacOpenCloseScope (opening,sc) ->
+        return (
+          keyword (if opening then "Open " else "Close ") ++
+            keyword "Scope" ++ spc() ++ str sc
+        )
+      | VernacDelimiters (sc,Some key) ->
+        return (
+          keyword "Delimit Scope" ++ spc () ++ str sc ++
+            spc() ++ keyword "with" ++ spc () ++ str key
+        )
+      | VernacDelimiters (sc, None) ->
+        return (
+          keyword "Undelimit Scope" ++ spc () ++ str sc
+        )
+      | VernacBindScope (sc,cll) ->
+        return (
+          keyword "Bind Scope" ++ spc () ++ str sc ++
+            spc() ++ keyword "with" ++ spc () ++ prlist_with_sep spc pr_class_rawexpr cll
+        )
+      | VernacInfix (({v=s},mv),q,sn) -> (* A Verifier *)
+        return (
+          hov 0 (hov 0 (keyword "Infix "
+                        ++ qs s ++ str " :=" ++ pr_constrarg q) ++
+                   pr_syntax_modifiers mv ++
+                   (match sn with
+                     | None -> mt()
+                     | Some sc -> spc() ++ str":" ++ spc() ++ str sc))
+        )
+      | VernacNotation (c,({v=s},l),opt) ->
+        return (
+          hov 2 (keyword "Notation" ++ spc() ++ qs s ++
+                   str " :=" ++ Flags.without_option Flags.beautify pr_constrarg c ++ pr_syntax_modifiers l ++
+                   (match opt with
+                     | None -> mt()
+                     | Some sc -> str" :" ++ spc() ++ str sc))
+        )
+      | VernacSyntaxExtension (_, (s, l)) ->
+        return (
+          keyword "Reserved Notation" ++ spc() ++ pr_ast qs s ++
+            pr_syntax_modifiers l
+        )
+      | VernacNotationAddFormat(s,k,v) ->
+        return (
+          keyword "Format Notation " ++ qs s ++ spc () ++ qs k ++ spc() ++ qs v
+        )
+
+      (* Gallina *)
+      | VernacDefinition ((discharge,kind),id,b) -> (* A verifier... *)
+        let pr_def_token dk =
+          keyword (
+            if Name.is_anonymous (fst id).v
+            then "Goal"
+            else Kindops.string_of_definition_object_kind dk)
+        in
+        let pr_reduce = function
+          | None -> mt()
+          | Some r ->
+            keyword "Eval" ++ spc() ++
+              pr_red_expr (pr_constr, pr_lconstr, pr_smart_global, pr_constr) keyword r ++
+              keyword " in" ++ spc()
+        in
+        let pr_def_body = function
+          | DefineBody (bl,red,body,d) ->
+            let ty = match d with
+              | None -> mt()
+              | Some ty -> spc() ++ str":" ++ pr_spc_lconstr ty
+            in
+            (pr_binders_arg bl,ty,Some (pr_reduce red ++ pr_lconstr body))
+          | ProveBody (bl,t) ->
+            let typ u = if (fst id).v = Anonymous then (assert (bl = []); u) else (str" :" ++ u) in
+            (pr_binders_arg bl, typ (pr_spc_lconstr t), None) in
+        let (binds,typ,c) = pr_def_body b in
+        return (
+          hov 2 (
+            pr_def_token kind ++ spc()
+            ++ pr_lname_decl id ++ binds ++ typ
+            ++ (match c with
+              | None -> mt()
+              | Some cc -> str" :=" ++ spc() ++ cc))
+        )
+
+      | VernacStartTheoremProof (ki,l) ->
+        return (
+          hov 1 (pr_statement (pr_thm_token ki) (List.hd l) ++
+                   prlist (pr_statement (spc () ++ keyword "with")) (List.tl l))
+        )
+
+      | VernacEndProof Admitted ->
+        return (keyword "Admitted")
+
+      | VernacEndProof (Proved (opac,o)) -> return (
+        let open Proof_global in
+        match o with
+          | None -> (match opac with
+              | Transparent -> keyword "Defined"
+              | Opaque      -> keyword "Qed")
+          | Some id -> (if opac <> Transparent then keyword "Save" else keyword "Defined") ++ spc() ++ pr_lident id
+      )
+      | VernacExactProof c ->
+        return (hov 2 (keyword "Proof" ++ pr_lconstrarg c))
+      | VernacAssumption ((discharge,kind),t,l) ->
+        let n = List.length (List.flatten (List.map fst (List.map snd l))) in
+        let pr_params (c, (xl, t)) =
+          hov 2 (prlist_with_sep sep pr_ident_decl xl ++ spc() ++
+            (if c then str":>" else str":" ++ spc() ++ pr_lconstr_expr t)) in
+        let assumptions = prlist_with_sep spc (fun p -> hov 1 (str "(" ++ pr_params p ++ str ")")) l in
+        return (hov 2 (pr_assumption_token (n > 1) discharge kind ++
+                       pr_non_empty_arg pr_assumption_inline t ++ spc() ++ assumptions))
+      | VernacInductive (cum, p,f,l) ->
+        let pr_constructor (coe,(id,c)) =
+          hov 2 (pr_lident id ++ str" " ++
+                   (if coe then str":>" else str":") ++
+                   Flags.without_option Flags.beautify pr_spc_lconstr c)
+        in
+        let pr_constructor_list b l = match l with
+          | Constructors [] -> mt()
+          | Constructors l ->
+            let fst_sep = match l with [_] -> "   " | _ -> " | " in
+            pr_com_at (begin_of_inductive l) ++
+              fnl() ++ str fst_sep ++
+              prlist_with_sep (fun _ -> fnl() ++ str" | ") pr_constructor l
+          | RecordDecl (c,fs) ->
+            pr_record_decl b c fs
+        in
+        let pr_oneind key (((coe,iddecl),indpar,s,k,lc),ntn) =
+          hov 0 (
+            str key ++ spc() ++
+              (if coe then str"> " else str"") ++ pr_ident_decl iddecl ++
+              pr_and_type_binders_arg indpar ++
+              pr_opt (fun s -> str":" ++ spc() ++ pr_lconstr_expr s) s ++
+              str" :=") ++ pr_constructor_list k lc ++
+            prlist (pr_decl_notation pr_constr) ntn
+        in
+        let key =
+          let (_,_,_,k,_),_ = List.hd l in
+          let kind =
+            match k with Record -> "Record" | Structure -> "Structure"
+                       | Inductive_kw -> "Inductive" | CoInductive -> "CoInductive"
+                       | Class _ -> "Class" | Variant -> "Variant"
+          in
+          if p then
+            let cm =
+              match cum with
+              | Some VernacCumulative -> "Cumulative"
+              | Some VernacNonCumulative -> "NonCumulative"
+              | None -> ""
+            in
+            cm ^ " " ^ kind
+          else kind
+        in
+        return (
+          hov 1 (pr_oneind key (List.hd l)) ++
+          (prlist (fun ind -> fnl() ++ hov 1 (pr_oneind "with" ind)) (List.tl l))
+        )
+
+      | VernacFixpoint (local, recs) ->
+        let local = match local with
+          | DoDischarge -> "Let "
+          | NoDischarge -> ""
+        in
+        return (
+          hov 0 (str local ++ keyword "Fixpoint" ++ spc () ++
+                   prlist_with_sep (fun _ -> fnl () ++ keyword "with"
+                     ++ spc ()) pr_rec_definition recs)
+        )
+
+      | VernacCoFixpoint (local, corecs) ->
+        let local = match local with
+          | DoDischarge -> keyword "Let" ++ spc ()
+          | NoDischarge -> str ""
+        in
+        let pr_onecorec ((iddecl,bl,c,def),ntn) =
+          pr_ident_decl iddecl ++ spc() ++ pr_binders bl ++ spc() ++ str":" ++
+            spc() ++ pr_lconstr_expr c ++
+            pr_opt (fun def -> str":=" ++ brk(1,2) ++ pr_lconstr def) def ++
+            prlist (pr_decl_notation pr_constr) ntn
+        in
+        return (
+          hov 0 (local ++ keyword "CoFixpoint" ++ spc() ++
+                   prlist_with_sep (fun _ -> fnl() ++ keyword "with" ++ spc ()) pr_onecorec corecs)
+        )
+      | VernacScheme l ->
+        return (
+          hov 2 (keyword "Scheme" ++ spc() ++
+                   prlist_with_sep (fun _ -> fnl() ++ keyword "with" ++ spc ()) pr_onescheme l)
+        )
+      | VernacCombinedScheme (id, l) ->
+        return (
+          hov 2 (keyword "Combined Scheme" ++ spc() ++
+                   pr_lident id ++ spc() ++ keyword "from" ++ spc() ++
+                   prlist_with_sep (fun _ -> fnl() ++ str", ") pr_lident l)
+        )
+      | VernacUniverse v ->
+        return (
+          hov 2 (keyword "Universe" ++ spc () ++
+                   prlist_with_sep (fun _ -> str",") pr_lident v)
+        )
+      | VernacConstraint v ->
+        return (
+          hov 2 (keyword "Constraint" ++ spc () ++
+                   prlist_with_sep (fun _ -> str",") pr_uconstraint v)
+        )
+
+      (* Gallina extensions *)
+      | VernacBeginSection id ->
+        return (hov 2 (keyword "Section" ++ spc () ++ pr_lident id))
+      | VernacEndSegment id ->
+        return (hov 2 (keyword "End" ++ spc() ++ pr_lident id))
+      | VernacNameSectionHypSet (id,set) ->
+        return (hov 2 (keyword "Package" ++ spc() ++ pr_lident id ++ spc()++
+        str ":="++spc()++pr_using set))
+      | VernacRequire (from, exp, l) ->
+        let from = match from with
+        | None -> mt ()
+        | Some r -> keyword "From" ++ spc () ++ pr_module r ++ spc ()
+        in
+        return (
+          hov 2
+            (from ++ keyword "Require" ++ spc() ++ pr_require_token exp ++
+               prlist_with_sep sep pr_module l)
+        )
+      | VernacImport (f,l) ->
+        return (
+          (if f then keyword "Export" else keyword "Import") ++ spc() ++
+            prlist_with_sep sep pr_import_module l
+        )
+      | VernacCanonical q ->
+        return (
+          keyword "Canonical Structure" ++ spc() ++ pr_smart_global q
+        )
+      | VernacCoercion (id,c1,c2) ->
+        return (
+          hov 1 (
+            keyword "Coercion" ++ spc() ++
+              pr_smart_global id ++ spc() ++ str":" ++ spc() ++ pr_class_rawexpr c1 ++
+              spc() ++ str">->" ++ spc() ++ pr_class_rawexpr c2)
+        )
+      | VernacIdentityCoercion (id,c1,c2) ->
+        return (
+          hov 1 (
+            keyword "Identity Coercion" ++ spc() ++ pr_lident id ++
+              spc() ++ str":" ++ spc() ++ pr_class_rawexpr c1 ++ spc() ++ str">->" ++
+              spc() ++ pr_class_rawexpr c2)
+        )
+
+      | VernacInstance (abst, sup, (instid, bk, cl), props, info) ->
+        return (
+          hov 1 (
+            (if abst then keyword "Declare" ++ spc () else mt ()) ++
+            keyword "Instance" ++
+            (match instid with
+             | {loc; v = Name id}, l -> spc () ++ pr_ident_decl (CAst.(make ?loc id),l) ++ spc ()
+             | { v = Anonymous }, _ -> mt ()) ++
+            pr_and_type_binders_arg sup ++
+              str":" ++ spc () ++
+              (match bk with Implicit -> str "! " | Explicit -> mt ()) ++
+              pr_constr cl ++ pr_hint_info pr_constr_pattern_expr info ++
+              (match props with
+                | Some (true, { v = CRecord l}) -> spc () ++ str":=" ++ spc () ++ str"{" ++ pr_record_body l ++ str "}"
+                | Some (true,_) -> assert false
+                | Some (false,p) -> spc () ++ str":=" ++ spc () ++ pr_constr p
+                | None -> mt()))
+        )
+
+      | VernacContext l ->
+        return (
+          hov 1 (
+            keyword "Context" ++ pr_and_type_binders_arg l)
+        )
+
+      | VernacDeclareInstances insts ->
+         let pr_inst (id, info) =
+           pr_reference id ++ pr_hint_info pr_constr_pattern_expr info
+         in
+         return (
+          hov 1 (keyword "Existing" ++ spc () ++
+                   keyword(String.plural (List.length insts) "Instance") ++
+                 spc () ++ prlist_with_sep (fun () -> str", ") pr_inst insts)
+        )
+
+      | VernacDeclareClass id ->
+        return (
+          hov 1 (keyword "Existing" ++ spc () ++ keyword "Class" ++ spc () ++ pr_reference id)
+        )
+
+      (* Modules and Module Types *)
+      | VernacDefineModule (export,m,bl,tys,bd) ->
+        let b = pr_module_binders bl pr_lconstr in
+        return (
+          hov 2 (keyword "Module" ++ spc() ++ pr_require_token export ++
+                   pr_lident m ++ b ++
+                   pr_of_module_type pr_lconstr tys ++
+                   (if List.is_empty bd then mt () else str ":= ") ++
+                   prlist_with_sep (fun () -> str " <+")
+                   (pr_module_ast_inl true pr_lconstr) bd)
+        )
+      | VernacDeclareModule (export,id,bl,m1) ->
+        let b = pr_module_binders bl pr_lconstr in
+        return (
+          hov 2 (keyword "Declare Module" ++ spc() ++ pr_require_token export ++
+                   pr_lident id ++ b ++ str " :" ++
+                   pr_module_ast_inl true pr_lconstr m1)
+        )
+      | VernacDeclareModuleType (id,bl,tyl,m) ->
+        let b = pr_module_binders bl pr_lconstr in
+        let pr_mt = pr_module_ast_inl true pr_lconstr in
+        return (
+          hov 2 (keyword "Module Type " ++ pr_lident id ++ b ++
+                   prlist_strict (fun m -> str " <:" ++ pr_mt m) tyl ++
+                   (if List.is_empty m then mt () else str ":= ") ++
+                   prlist_with_sep (fun () -> str " <+ ") pr_mt m)
+        )
+      | VernacInclude (mexprs) ->
+        let pr_m = pr_module_ast_inl false pr_lconstr in
+        return (
+          hov 2 (keyword "Include" ++ spc() ++
+                   prlist_with_sep (fun () -> str " <+ ") pr_m mexprs)
+        )
+      (* Solving *)
+      | VernacSolveExistential (i,c) ->
+        return (keyword "Existential" ++ spc () ++ int i ++ pr_lconstrarg c)
+
+      (* Auxiliary file and library management *)
+      | VernacAddLoadPath (fl,s,d) ->
+        return (
+          hov 2
+            (keyword "Add" ++
+               (if fl then spc () ++ keyword "Rec" ++ spc () else spc()) ++
+               keyword "LoadPath" ++ spc() ++ qs s ++
+               (match d with
+                 | None -> mt()
+                 | Some dir -> spc() ++ keyword "as" ++ spc() ++ DirPath.print dir))
+        )
+      | VernacRemoveLoadPath s ->
+        return (keyword "Remove LoadPath" ++ qs s)
+      | VernacAddMLPath (fl,s) ->
+        return (
+          keyword "Add"
+          ++ (if fl then spc () ++ keyword "Rec" ++ spc () else spc())
+          ++ keyword "ML Path"
+          ++ qs s
+        )
+      | VernacDeclareMLModule (l) ->
+        return (
+          hov 2 (keyword "Declare ML Module" ++ spc() ++ prlist_with_sep sep qs l)
+        )
+      | VernacChdir s ->
+        return (keyword "Cd" ++ pr_opt qs s)
+
+      (* Commands *)
+      | VernacCreateHintDb (dbname,b) ->
+        return (
+          hov 1 (keyword "Create HintDb" ++ spc () ++
+                   str dbname ++ (if b then str" discriminated" else mt ()))
+        )
+      | VernacRemoveHints (dbnames, ids) ->
+        return (
+          hov 1 (keyword "Remove Hints" ++ spc () ++
+                   prlist_with_sep spc (fun r -> pr_id (coerce_reference_to_id r)) ids ++
+                   pr_opt_hintbases dbnames)
+        )
+      | VernacHints (dbnames,h) ->
+        return (pr_hints dbnames h pr_constr pr_constr_pattern_expr)
+      | VernacSyntacticDefinition (id,(ids,c),compat) ->
+        return (
+          hov 2
+            (keyword "Notation" ++ spc () ++ pr_lident id ++ spc () ++
+               prlist_with_sep spc pr_id ids ++ str":=" ++ pr_constrarg c ++
+               pr_syntax_modifiers
+               (match compat with
+                | None -> []
+                | Some Flags.Current -> [SetOnlyParsing]
+                | Some v -> [SetCompatVersion v]))
+        )
+      | VernacArguments (q, args, more_implicits, nargs, mods) ->
+        return (
+          hov 2 (
+            keyword "Arguments" ++ spc() ++
+              pr_smart_global q ++
+              let pr_s = function None -> str"" | Some {v=s} -> str "%" ++ str s in
+              let pr_if b x = if b then x else str "" in
+              let pr_br imp x = match imp with
+                | Vernacexpr.Implicit -> str "[" ++ x ++ str "]"
+                | Vernacexpr.MaximallyImplicit -> str "{" ++ x ++ str "}"
+                | Vernacexpr.NotImplicit -> x in
+              let rec print_arguments n l =
+                match n, l with
+                  | Some 0, l -> spc () ++ str"/" ++ print_arguments None l
+                  | _, [] -> mt()
+                  | n, { name = id; recarg_like = k;
+                         notation_scope = s;
+                         implicit_status = imp } :: tl ->
+                    spc() ++ pr_br imp (pr_if k (str"!") ++ Name.print id ++ pr_s s) ++
+                      print_arguments (Option.map pred n) tl
+              in
+              let rec print_implicits = function
+                | [] -> mt ()
+                | (name, impl) :: rest ->
+                   spc() ++ pr_br impl (Name.print name) ++ print_implicits rest
+              in
+              print_arguments nargs args ++
+                if not (List.is_empty more_implicits) then
+                  prlist (fun l -> str"," ++ print_implicits l) more_implicits
+                else (mt ()) ++
+                (if not (List.is_empty mods) then str" : " else str"") ++
+                  prlist_with_sep (fun () -> str", " ++ spc()) (function
+                    | `ReductionDontExposeCase -> keyword "simpl nomatch"
+                    | `ReductionNeverUnfold -> keyword "simpl never"
+                    | `DefaultImplicits -> keyword "default implicits"
+                    | `Rename -> keyword "rename"
+                    | `Assert -> keyword "assert"
+                    | `ExtraScopes -> keyword "extra scopes"
+                    | `ClearImplicits -> keyword "clear implicits"
+                    | `ClearScopes -> keyword "clear scopes")
+                  mods)
+        )
+      | VernacReserve bl ->
+        let n = List.length (List.flatten (List.map fst bl)) in
+        return (
+          hov 2 (tag_keyword (str"Implicit Type" ++ str (if n > 1 then "s " else " "))
+                 ++ pr_ne_params_list pr_lconstr_expr (List.map (fun sb -> false,sb) bl))
+        )
+      | VernacGeneralizable g ->
+        return (
+          hov 1 (tag_keyword (
+            str"Generalizable Variable" ++
+              match g with
+                | None -> str "s none"
+                | Some [] -> str "s all"
+                | Some idl ->
+                  str (if List.length idl > 1 then "s " else " ") ++
+                    prlist_with_sep spc pr_lident idl)
+          ))
+      | VernacSetOpacity(k,l) when Conv_oracle.is_transparent k ->
+        return (
+          hov 1 (keyword "Transparent" ++
+                   spc() ++ prlist_with_sep sep pr_smart_global l)
+        )
+      | VernacSetOpacity(Conv_oracle.Opaque,l) ->
+        return (
+          hov 1 (keyword "Opaque" ++
+                   spc() ++ prlist_with_sep sep pr_smart_global l)
+        )
+      | VernacSetOpacity _ ->
+        return (
+          CErrors.anomaly (keyword "VernacSetOpacity used to set something else.")
+        )
+      | VernacSetStrategy l ->
+        let pr_lev = function
+          | Conv_oracle.Opaque -> keyword "opaque"
+          | Conv_oracle.Expand -> keyword "expand"
+          | l when Conv_oracle.is_transparent l -> keyword "transparent"
+          | Conv_oracle.Level n -> int n
+        in
+        let pr_line (l,q) =
+          hov 2 (pr_lev l ++ spc() ++
+                   str"[" ++ prlist_with_sep sep pr_smart_global q ++ str"]")
+        in
+        return (
+          hov 1 (keyword "Strategy" ++ spc() ++
+                   hv 0 (prlist_with_sep sep pr_line l))
+        )
+      | VernacUnsetOption (export, na) ->
+        let export = if export then keyword "Export" ++ spc () else mt () in
+        return (
+          hov 1 (export ++ keyword "Unset" ++ spc() ++ pr_printoption na None)
+        )
+      | VernacSetOption (export, na,v) ->
+        let export = if export then keyword "Export" ++ spc () else mt () in
+        return (
+          hov 2 (export ++ keyword "Set" ++ spc() ++ pr_set_option na v)
+        )
+      | VernacAddOption (na,l) ->
+        return (
+          hov 2 (keyword "Add" ++ spc() ++ pr_printoption na (Some l))
+        )
+      | VernacRemoveOption (na,l) ->
+        return (
+          hov 2 (keyword "Remove" ++ spc() ++ pr_printoption na (Some l))
+        )
+      | VernacMemOption (na,l) ->
+        return (
+          hov 2 (keyword "Test" ++ spc() ++ pr_printoption na (Some l))
+        )
+      | VernacPrintOption na ->
+        return (
+          hov 2 (keyword "Test" ++ spc() ++ pr_printoption na None)
+        )
+      | VernacCheckMayEval (r,io,c) ->
+        let pr_mayeval r c = match r with
+          | Some r0 ->
+            hov 2 (keyword "Eval" ++ spc() ++
+                     pr_red_expr (pr_constr,pr_lconstr,pr_smart_global, pr_constr) keyword r0 ++
+                     spc() ++ keyword "in" ++ spc () ++ pr_lconstr c)
+          | None -> hov 2 (keyword "Check" ++ spc() ++ pr_lconstr c)
+        in
+        let pr_i = match io with None -> mt ()
+                               | Some i -> Goal_select.pr_goal_selector i ++ str ": " in
+        return (pr_i ++ pr_mayeval r c)
+      | VernacGlobalCheck c ->
+        return (hov 2 (keyword "Type" ++ pr_constrarg c))
+      | VernacDeclareReduction (s,r) ->
+        return (
+          keyword "Declare Reduction" ++ spc () ++ str s ++ str " := " ++
+            pr_red_expr (pr_constr,pr_lconstr,pr_smart_global, pr_constr) keyword r
+        )
+      | VernacPrint p ->
+        return (pr_printable p)
+      | VernacSearch (sea,g,sea_r) ->
+        return (pr_search sea g sea_r pr_constr_pattern_expr)
+      | VernacLocate loc ->
+        let pr_locate =function
+          | LocateAny qid -> pr_smart_global qid
+          | LocateTerm qid -> keyword "Term" ++ spc() ++ pr_smart_global qid
+          | LocateFile f -> keyword "File" ++ spc() ++ qs f
+          | LocateLibrary qid -> keyword "Library" ++ spc () ++ pr_module qid
+          | LocateModule qid -> keyword "Module" ++ spc () ++ pr_module qid
+          | LocateOther (s, qid) -> keyword s ++ spc () ++ pr_ltac_ref qid
+        in
+        return (keyword "Locate" ++ spc() ++ pr_locate loc)
+      | VernacRegister (id, RegisterInline) ->
+        return (
+          hov 2
+            (keyword "Register Inline" ++ spc() ++ pr_lident id)
+        )
+      | VernacComments l ->
+        return (
+          hov 2
+            (keyword "Comments" ++ spc()
+             ++ prlist_with_sep sep (pr_comment pr_constr) l)
+        )
+
+      (* For extension *)
+      | VernacExtend (s,c) ->
+        return (pr_extend s c)
+      | VernacProof (None, None) ->
+        return (keyword "Proof")
+      | VernacProof (None, Some e) ->
+        return (keyword "Proof " ++ spc () ++
+            keyword "using" ++ spc() ++ pr_using e)
+      | VernacProof (Some te, None) ->
+        return (keyword "Proof with" ++ spc() ++ Pputils.pr_raw_generic (Global.env ()) te)
+      | VernacProof (Some te, Some e) ->
+        return (
+          keyword "Proof" ++ spc () ++
+            keyword "using" ++ spc() ++ pr_using e ++ spc() ++
+            keyword "with" ++ spc() ++ Pputils.pr_raw_generic (Global.env ()) te
+        )
+      | VernacProofMode s ->
+        return (keyword "Proof Mode" ++ str s)
+      | VernacBullet b ->
+        (* XXX: Redundant with Proof_bullet.print *)
+        return (let open Proof_bullet in begin match b with
+          | Dash n -> str (String.make n '-')
+          | Star n -> str (String.make n '*')
+          | Plus n -> str (String.make n '+')
+        end)
+      | VernacSubproof None ->
+        return (str "{")
+      | VernacSubproof (Some i) ->
+        return (Goal_select.pr_goal_selector i ++ str ":" ++ spc () ++ str "{")
+      | VernacEndSubproof ->
+        return (str "}")
+
+let pr_vernac_flag =
+  function
+  | VernacPolymorphic true -> keyword "Polymorphic"
+  | VernacPolymorphic false -> keyword "Monomorphic"
+  | VernacProgram -> keyword "Program"
+  | VernacLocal local -> pr_locality local
+
+  let rec pr_vernac_control v =
+    let return = tag_vernac v in
+    match v with
+    | VernacExpr (f, v') ->
+      List.fold_right
+        (fun f a -> pr_vernac_flag f ++ spc() ++ a)
+        f
+        (pr_vernac_expr v' ++ sep_end v')
+    | VernacTime (_,{v}) ->
+      return (keyword "Time" ++ spc() ++ pr_vernac_control v)
+    | VernacRedirect (s, {v}) ->
+      return (keyword "Redirect" ++ spc() ++ qs s ++ spc() ++ pr_vernac_control v)
+    | VernacTimeout(n,v) ->
+      return (keyword "Timeout " ++ int n ++ spc() ++ pr_vernac_control v)
+    | VernacFail v ->
+      return (keyword "Fail" ++ spc() ++ pr_vernac_control v)
+
+    let pr_vernac v =
+      try pr_vernac_control v
+      with e -> CErrors.print e
diff --git a/vernac/ppvernac.mli b/vernac/ppvernac.mli
new file mode 100644
index 000000000..4aa24bf5d
--- /dev/null
+++ b/vernac/ppvernac.mli
@@ -0,0 +1,26 @@
+(************************************************************************)
+(*         *   The Coq Proof Assistant / The Coq Development Team       *)
+(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2018       *)
+(* <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)         *)
+(************************************************************************)
+
+(** This module implements pretty-printers for vernac_expr syntactic
+    objects and their subcomponents. *)
+
+val pr_set_entry_type : ('a -> Pp.t) -> 'a Extend.constr_entry_key_gen -> Pp.t
+
+(** Prints a fixpoint body *)
+val pr_rec_definition : (Vernacexpr.fixpoint_expr * Vernacexpr.decl_notation list) -> Pp.t
+
+(** Prints a vernac expression without dot *)
+val pr_vernac_expr : Vernacexpr.vernac_expr -> Pp.t
+
+(** Prints a "proof using X" clause. *)
+val pr_using : Vernacexpr.section_subset_expr -> Pp.t
+
+(** Prints a vernac expression and closes it with a dot. *)
+val pr_vernac : Vernacexpr.vernac_control -> Pp.t
diff --git a/vernac/vernac.mllib b/vernac/vernac.mllib
index f001b572a..6fceda56d 100644
--- a/vernac/vernac.mllib
+++ b/vernac/vernac.mllib
@@ -1,10 +1,14 @@
 Vernacprop
-Proof_using
-Lemmas
 Himsg
 ExplainErr
-Class
 Locality
+Egramml
+Vernacinterp
+Ppvernac
+Proof_using
+Lemmas
+Class
+Egramcoq
 Metasyntax
 Auto_ind_decl
 Search
@@ -20,7 +24,6 @@ Classes
 Record
 Assumptions
 Vernacstate
-Vernacinterp
 Mltop
 Topfmt
 Vernacentries