catala/compiler/shared_ast/var.mli

(* This file is part of the Catala compiler, a specification language for tax
   and social benefits computation rules. Copyright (C) 2020-2022 Inria,
   contributor: Louis Gesbert <louis.gesbert@inria.fr>

   Licensed under the Apache License, Version 2.0 (the "License"); you may not
   use this file except in compliance with the License. You may obtain a copy of
   the License at

   http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
   License for the specific language governing permissions and limitations under
   the License. *)

open Definitions

(** {1 Variables and their collections} *)

(** This module provides types and helpers for Bindlib variables on the [gexpr]
    type *)

type 'e t = ('a, 't) naked_gexpr Bindlib.var constraint 'e = ('a any, 't) gexpr

type 'e vars = ('a, 't) naked_gexpr Bindlib.mvar
  constraint 'e = ('a any, 't) gexpr

val make : string -> 'e t
val compare : 'e t -> 'e t -> int
val eq : 'e t -> 'e t -> bool

val translate : 'e1 t -> 'e2 t
(** Needed when converting from one AST type to another. See the note of caution
    on [Bindlib.copy_var]. *)

type 'e var = 'e t
(** Alias to allow referring to the type in the submodules *)

(** Wrapper over [Set.S] but with a type variable for the AST type parameters.
    Extend as needed *)
module Set : sig
  type 'e t

  val empty : 'e t
  val singleton : 'e var -> 'e t
  val add : 'e var -> 'e t -> 'e t
  val remove : 'e var -> 'e t -> 'e t
  val union : 'e t -> 'e t -> 'e t
  val mem : 'e var -> 'e t -> bool
  val of_list : 'e var list -> 'e t
  val elements : 'e t -> 'e var list
  val diff : 'e t -> 'e t -> 'e t
end

(** Wrapper over [Map.S] but with a type variable for the AST type parameters.
    Extend as needed *)
module Map : sig
  type ('e, 'x) t

  val empty : ('e, 'x) t
  val singleton : 'e var -> 'x -> ('e, 'x) t
  val add : 'e var -> 'x -> ('e, 'x) t -> ('e, 'x) t
  val update : 'e var -> ('x option -> 'x option) -> ('e, 'x) t -> ('e, 'x) t
  val find : 'e var -> ('e, 'x) t -> 'x
  val find_opt : 'e var -> ('e, 'x) t -> 'x option
  val bindings : ('e, 'x) t -> ('e var * 'x) list
  val mem : 'e var -> ('e, 'x) t -> bool

  val union :
    ('e var -> 'x -> 'x -> 'x option) -> ('e, 'x) t -> ('e, 'x) t -> ('e, 'x) t

  val fold : ('e var -> 'x -> 'acc -> 'acc) -> ('e, 'x) t -> 'acc -> 'acc
end