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+open Names
+open Glob_term
+
+(** {5 Maps of pattern variables} *)
+
+(** Type [constr_under_binders] is for representing the term resulting
+    of a matching. Matching can return terms defined in a some context
+    of named binders; in the context, variable names are ordered by
+    (<) and referred to by index in the term Thanks to the canonical
+    ordering, a matching problem like
+
+    [match ... with [(fun x y => ?p,fun y x => ?p)] => [forall x y => p]]
+
+    will be accepted. Thanks to the reference by index, a matching
+    problem like
+
+    [match ... with [(fun x => ?p)] => [forall x => p]]
+
+    will work even if [x] is also the name of an existing goal
+    variable.
+
+    Note: we do not keep types in the signature. Besides simplicity,
+    the main reason is that it would force to close the signature over
+    binders that occur only in the types of effective binders but not
+    in the term itself (e.g. for a term [f x] with [f:A -> True] and
+    [x:A]).
+
+    On the opposite side, by not keeping the types, we loose
+    opportunity to propagate type informations which otherwise would
+    not be inferable, as e.g. when matching [forall x, x = 0] with
+    pattern [forall x, ?h = 0] and using the solution "x|-h:=x" in
+    expression [forall x, h = x] where nothing tells how the type of x
+    could be inferred. We also loose the ability of typing ltac
+    variables before calling the right-hand-side of ltac matching clauses. *)
+
+type constr_under_binders = Id.t list * EConstr.constr
+
+(** Types of substitutions with or w/o bound variables *)
+
+type patvar_map = EConstr.constr Id.Map.t
+type extended_patvar_map = constr_under_binders Id.Map.t
+
+(** A globalised term together with a closure representing the value
+    of its free variables. Intended for use when these variables are taken
+    from the Ltac environment. *)
+type closure = {
+  idents:Id.t Id.Map.t;
+  typed: constr_under_binders Id.Map.t ;
+  untyped:closed_glob_constr Id.Map.t }
+and closed_glob_constr = {
+  closure: closure;
+  term: glob_constr }
+
+(** Ltac variable maps *)
+type var_map = constr_under_binders Id.Map.t
+type uconstr_var_map = closed_glob_constr Id.Map.t
+type unbound_ltac_var_map = Geninterp.Val.t Id.Map.t
+
+type ltac_var_map = {
+  ltac_constrs : var_map;
+  (** Ltac variables bound to constrs *)
+  ltac_uconstrs : uconstr_var_map;
+  (** Ltac variables bound to untyped constrs *)
+  ltac_idents: Id.t Id.Map.t;
+  (** Ltac variables bound to identifiers *)
+  ltac_genargs : unbound_ltac_var_map;
+  (** Ltac variables bound to other kinds of arguments *)
+}