(**************************************************************************)
(* *)
(* OCaml *)
(* *)
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1996 Institut National de Recherche en Informatique et *)
(* en Automatique. *)
(* *)
(* All rights reserved. This file is distributed under the terms of *)
(* the GNU Lesser General Public License version 2.1, with the *)
(* special exception on linking described in the file LICENSE. *)
(* *)
(**************************************************************************)
(** Detection of partial matches and unused match cases. *)
open Asttypes
open Typedtree
open Types
val omega : pattern
(** aka. "Tpat_any" or "_" *)
val omegas : int -> pattern list
(** [List.init (fun _ -> omega)] *)
val omega_list : 'a list -> pattern list
(** [List.map (fun _ -> omega)] *)
val normalize_pat : pattern -> pattern
(** Keep only the "head" of a pattern: all arguments are replaced by [omega], so
are variables. *)
val const_compare : constant -> constant -> int
(** [const_compare c1 c2] compares the actual values represented by [c1] and
[c2], while simply using [Pervasives.compare] would compare the
representations.
cf. MPR#5758 *)
val le_pat : pattern -> pattern -> bool
(** [le_pat p q] means: forall V, V matches q implies V matches p *)
val le_pats : pattern list -> pattern list -> bool
(** [le_pats (p1 .. pm) (q1 .. qn)] means: forall i <= m, [le_pat pi qi] *)
(** Exported compatibility functor, abstracted over constructor equality *)
module Compat :
functor
(Constr: sig
val equal :
Types.constructor_description ->
Types.constructor_description ->
bool
end) -> sig
val compat : pattern -> pattern -> bool
val compats : pattern list -> pattern list -> bool
end
exception Empty
val lub : pattern -> pattern -> pattern
(** [lub p q] is a pattern that matches all values matched by [p] and [q].
May raise [Empty], when [p] and [q] are not compatible. *)
val lubs : pattern list -> pattern list -> pattern list
(** [lubs [p1; ...; pn] [q1; ...; qk]], where [n < k], is
[[lub p1 q1; ...; lub pk qk]]. *)
val get_mins : ('a -> 'a -> bool) -> 'a list -> 'a list
(** Those two functions recombine one pattern and its arguments:
For instance:
(_,_)::p1::p2::rem -> (p1, p2)::rem
The second one will replace mutable arguments by '_'
*)
val set_args : pattern -> pattern list -> pattern list
val set_args_erase_mutable : pattern -> pattern list -> pattern list
val pat_of_constr : pattern -> constructor_description -> pattern
val complete_constrs :
pattern -> constructor_tag list -> constructor_description list
(** [ppat_of_type] builds an untyped or-pattern from its expected type.
May raise [Empty] when [type_expr] is an empty variant *)
val ppat_of_type :
Env.t -> type_expr ->
Parsetree.pattern *
(string, constructor_description) Hashtbl.t *
(string, label_description) Hashtbl.t
val pressure_variants: Env.t -> pattern list -> unit
val check_partial:
((string, constructor_description) Hashtbl.t ->
(string, label_description) Hashtbl.t ->
Parsetree.pattern -> pattern option) ->
Location.t -> case list -> partial
val check_unused:
(bool ->
(string, constructor_description) Hashtbl.t ->
(string, label_description) Hashtbl.t ->
Parsetree.pattern -> pattern option) ->
case list -> unit
(* Irrefutability tests *)
val irrefutable : pattern -> bool
(** An inactive pattern is a pattern, matching against which can be duplicated, erased or
delayed without change in observable behavior of the program. Patterns containing
(lazy _) subpatterns or reads of mutable fields are active. *)
val inactive : partial:partial -> pattern -> bool
(* Ambiguous bindings *)
val check_ambiguous_bindings : case list -> unit
(* The tag used for open polymorphic variant types with an abstract row *)
val some_private_tag : label
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