ocaml/typing/printtyp.ml

2245 lines
72 KiB
OCaml

(**************************************************************************)
(* *)
(* OCaml *)
(* *)
(* Xavier Leroy and Jerome Vouillon, 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. *)
(* *)
(**************************************************************************)
(* Printing functions *)
open Misc
open Ctype
open Format
open Longident
open Path
open Asttypes
open Types
open Btype
open Outcometree
module String = Misc.Stdlib.String
(* Print a long identifier *)
let rec longident ppf = function
| Lident s -> pp_print_string ppf s
| Ldot(p, s) -> fprintf ppf "%a.%s" longident p s
| Lapply(p1, p2) -> fprintf ppf "%a(%a)" longident p1 longident p2
let () = Env.print_longident := longident
(* Print an identifier avoiding name collisions *)
module Out_name = struct
let create x = { printed_name = x }
let print x = x.printed_name
let set out_name x = out_name.printed_name <- x
end
(* printing environment for path shortening and naming *)
let printing_env = ref Env.empty
(* When printing, it is important to only observe the
current printing environment, without reading any new
cmi present on the file system *)
let in_printing_env f = Env.without_cmis f !printing_env
let human_unique n id = Printf.sprintf "%s/%d" (Ident.name id) n
type namespace =
| Type
| Module
| Module_type
| Class
| Class_type
| Other (** Other bypasses the unique name identifier mechanism *)
module Namespace = struct
let id = function
| Type -> 0
| Module -> 1
| Module_type -> 2
| Class -> 3
| Class_type -> 4
| Other -> 5
let size = 1 + id Other
let show =
function
| Type -> "type"
| Module -> "module"
| Module_type -> "module type"
| Class -> "class"
| Class_type -> "class type"
| Other -> ""
let pp ppf x = Format.pp_print_string ppf (show x)
(** The two functions below should never access the filesystem,
and thus use {!in_printing_env} rather than directly
accessing the printing environment *)
let lookup =
let to_lookup f lid = fst @@ in_printing_env (f (Lident lid)) in
function
| Type -> to_lookup Env.find_type_by_name
| Module -> to_lookup Env.find_module_by_name
| Module_type -> to_lookup Env.find_modtype_by_name
| Class -> to_lookup Env.find_class_by_name
| Class_type -> to_lookup Env.find_cltype_by_name
| Other -> fun _ -> raise Not_found
let location namespace id =
let path = Path.Pident id in
try Some (
match namespace with
| Type -> (in_printing_env @@ Env.find_type path).type_loc
| Module -> (in_printing_env @@ Env.find_module path).md_loc
| Module_type -> (in_printing_env @@ Env.find_modtype path).mtd_loc
| Class -> (in_printing_env @@ Env.find_class path).cty_loc
| Class_type -> (in_printing_env @@ Env.find_cltype path).clty_loc
| Other -> Location.none
) with Not_found -> None
let best_class_namespace = function
| Papply _ | Pdot _ -> Module
| Pident c ->
match location Class c with
| Some _ -> Class
| None -> Class_type
end
(** {2 Conflicts printing}
Conflicts arise when multiple items are attributed the same name,
the following module stores the global conflict references and
provides the printing functions for explaining the source of
the conflicts.
*)
module Conflicts = struct
module M = String.Map
type explanation =
{ kind: namespace; name:string; root_name:string; location:Location.t}
let explanations = ref M.empty
let collect_explanation namespace n id =
let name = human_unique n id in
let root_name = Ident.name id in
if not (M.mem name !explanations) then
match Namespace.location namespace id with
| None -> ()
| Some location ->
let explanation = { kind = namespace; location; name; root_name } in
explanations := M.add name explanation !explanations
let pp_explanation ppf r=
Format.fprintf ppf "@[<v 2>%a:@,Definition of %s %s@]"
Location.print_loc r.location (Namespace.show r.kind) r.name
let print_located_explanations ppf l =
Format.fprintf ppf "@[<v>%a@]" (Format.pp_print_list pp_explanation) l
let reset () = explanations := M.empty
let list_explanations () =
let c = !explanations in
reset ();
c |> M.bindings |> List.map snd |> List.sort Stdlib.compare
let print_toplevel_hint ppf l =
let conj ppf () = Format.fprintf ppf " and@ " in
let pp_namespace_plural ppf n = Format.fprintf ppf "%as" Namespace.pp n in
let root_names = List.map (fun r -> r.kind, r.root_name) l in
let unique_root_names = List.sort_uniq Stdlib.compare root_names in
let submsgs = Array.make Namespace.size [] in
let () = List.iter (fun (n,_ as x) ->
submsgs.(Namespace.id n) <- x :: submsgs.(Namespace.id n)
) unique_root_names in
let pp_submsg ppf names =
match names with
| [] -> ()
| [namespace, a] ->
Format.fprintf ppf
"@ \
@[<2>Hint: The %a %s has been defined multiple times@ \
in@ this@ toplevel@ session.@ \
Some toplevel values still refer to@ old@ versions@ of@ this@ %a.\
@ Did you try to redefine them?@]"
Namespace.pp namespace a Namespace.pp namespace
| (namespace, _) :: _ :: _ ->
Format.fprintf ppf
"@ \
@[<2>Hint: The %a %a have been defined multiple times@ \
in@ this@ toplevel@ session.@ \
Some toplevel values still refer to@ old@ versions@ of@ those@ %a.\
@ Did you try to redefine them?@]"
pp_namespace_plural namespace
Format.(pp_print_list ~pp_sep:conj pp_print_string) (List.map snd names)
pp_namespace_plural namespace in
Array.iter (pp_submsg ppf) submsgs
let print_explanations ppf =
let ltop, l =
(* isolate toplevel locations, since they are too imprecise *)
let from_toplevel a =
a.location.Location.loc_start.Lexing.pos_fname = "//toplevel//" in
List.partition from_toplevel (list_explanations ())
in
begin match l with
| [] -> ()
| l -> Format.fprintf ppf "@ %a" print_located_explanations l
end;
(* if there are name collisions in a toplevel session,
display at least one generic hint by namespace *)
print_toplevel_hint ppf ltop
let exists () = M.cardinal !explanations >0
end
module Naming_context = struct
module M = String.Map
module S = String.Set
let enabled = ref true
let enable b = enabled := b
(** Name mapping *)
type mapping =
| Need_unique_name of int Ident.Map.t
(** The same name has already been attributed to multiple types.
The [map] argument contains the specific binding time attributed to each
types.
*)
| Uniquely_associated_to of Ident.t * out_name
(** For now, the name [Ident.name id] has been attributed to [id],
[out_name] is used to expand this name if a conflict arises
at a later point
*)
| Associated_to_pervasives of out_name
(** [Associated_to_pervasives out_name] is used when the item
[Stdlib.$name] has been associated to the name [$name].
Upon a conflict, this name will be expanded to ["Stdlib." ^ name ] *)
let hid_start = 0
let add_hid_id id map =
let new_id = 1 + Ident.Map.fold (fun _ -> max) map hid_start in
new_id, Ident.Map.add id new_id map
let find_hid id map =
try Ident.Map.find id map, map with
Not_found -> add_hid_id id map
let pervasives name = "Stdlib." ^ name
let map = Array.make Namespace.size M.empty
let get namespace = map.(Namespace.id namespace)
let set namespace x = map.(Namespace.id namespace) <- x
(* Names used in recursive definitions are not considered when determining
if a name is already attributed in the current environment.
This is a weaker version of hidden_rec_items used by short-path. *)
let protected = ref S.empty
let add_protected id = protected := S.add (Ident.name id) !protected
let reset_protected () = protected := S.empty
let with_hidden id f =
protect_refs [ R(protected,S.add (Ident.name id) !protected)] f
let pervasives_name namespace name =
if not !enabled then Out_name.create name else
match M.find name (get namespace) with
| Associated_to_pervasives r -> r
| Need_unique_name _ -> Out_name.create (pervasives name)
| Uniquely_associated_to (id',r) ->
let hid, map = add_hid_id id' Ident.Map.empty in
Out_name.set r (human_unique hid id');
Conflicts.collect_explanation namespace hid id';
set namespace @@ M.add name (Need_unique_name map) (get namespace);
Out_name.create (pervasives name)
| exception Not_found ->
let r = Out_name.create name in
set namespace @@ M.add name (Associated_to_pervasives r) (get namespace);
r
(** Lookup for preexisting named item within the current {!printing_env} *)
let env_ident namespace name =
if S.mem name !protected then None else
match Namespace.lookup namespace name with
| Pident id -> Some id
| _ -> None
| exception Not_found -> None
(** Associate a name to the identifier [id] within [namespace] *)
let ident_name_simple namespace id =
if not !enabled then Out_name.create (Ident.name id) else
let name = Ident.name id in
match M.find name (get namespace) with
| Uniquely_associated_to (id',r) when Ident.same id id' ->
r
| Need_unique_name map ->
let hid, m = find_hid id map in
Conflicts.collect_explanation namespace hid id;
set namespace @@ M.add name (Need_unique_name m) (get namespace);
Out_name.create (human_unique hid id)
| Uniquely_associated_to (id',r) ->
let hid', m = find_hid id' Ident.Map.empty in
let hid, m = find_hid id m in
Out_name.set r (human_unique hid' id');
List.iter (fun (id,hid) -> Conflicts.collect_explanation namespace hid id)
[id, hid; id', hid' ];
set namespace @@ M.add name (Need_unique_name m) (get namespace);
Out_name.create (human_unique hid id)
| Associated_to_pervasives r ->
Out_name.set r ("Stdlib." ^ Out_name.print r);
let hid, m = find_hid id Ident.Map.empty in
set namespace @@ M.add name (Need_unique_name m) (get namespace);
Out_name.create (human_unique hid id)
| exception Not_found ->
let r = Out_name.create name in
set namespace
@@ M.add name (Uniquely_associated_to (id,r) ) (get namespace);
r
(** Same as {!ident_name_simple} but lookup to existing named identifiers
in the current {!printing_env} *)
let ident_name namespace id =
begin match env_ident namespace (Ident.name id) with
| Some id' -> ignore (ident_name_simple namespace id')
| None -> ()
end;
ident_name_simple namespace id
let reset () =
Array.iteri ( fun i _ -> map.(i) <- M.empty ) map
end
let ident_name = Naming_context.ident_name
let reset_naming_context = Naming_context.reset
let ident ppf id = pp_print_string ppf
(Out_name.print (Naming_context.ident_name_simple Other id))
(* Print a path *)
let ident_stdlib = Ident.create_persistent "Stdlib"
let non_shadowed_pervasive = function
| Pdot(Pident id, s) as path ->
Ident.same id ident_stdlib &&
(match in_printing_env (Env.find_type_by_name (Lident s)) with
| (path', _) -> Path.same path path'
| exception Not_found -> true)
| _ -> false
let find_double_underscore s =
let len = String.length s in
let rec loop i =
if i + 1 >= len then
None
else if s.[i] = '_' && s.[i + 1] = '_' then
Some i
else
loop (i + 1)
in
loop 0
let rec module_path_is_an_alias_of env path ~alias_of =
match Env.find_module path env with
| { md_type = Mty_alias path'; _ } ->
Path.same path' alias_of ||
module_path_is_an_alias_of env path' ~alias_of
| _ -> false
| exception Not_found -> false
(* Simple heuristic to print Foo__bar.* as Foo.Bar.* when Foo.Bar is an alias
for Foo__bar. This pattern is used by the stdlib. *)
let rec rewrite_double_underscore_paths env p =
match p with
| Pdot (p, s) ->
Pdot (rewrite_double_underscore_paths env p, s)
| Papply (a, b) ->
Papply (rewrite_double_underscore_paths env a,
rewrite_double_underscore_paths env b)
| Pident id ->
let name = Ident.name id in
match find_double_underscore name with
| None -> p
| Some i ->
let better_lid =
Ldot
(Lident (String.sub name 0 i),
String.capitalize_ascii
(String.sub name (i + 2) (String.length name - i - 2)))
in
match Env.find_module_by_name better_lid env with
| exception Not_found -> p
| p', _ ->
if module_path_is_an_alias_of env p' ~alias_of:p then
p'
else
p
let rewrite_double_underscore_paths env p =
if env == Env.empty then
p
else
rewrite_double_underscore_paths env p
let rec tree_of_path namespace = function
| Pident id ->
Oide_ident (ident_name namespace id)
| Pdot(_, s) as path when non_shadowed_pervasive path ->
Oide_ident (Naming_context.pervasives_name namespace s)
| Pdot(Pident t, s)
when namespace=Type && not (Path.is_uident (Ident.name t)) ->
(* [t.A]: inline record of the constructor [A] from type [t] *)
Oide_dot (Oide_ident (ident_name Type t), s)
| Pdot(p, s) ->
Oide_dot (tree_of_path Module p, s)
| Papply(p1, p2) ->
Oide_apply (tree_of_path Module p1, tree_of_path Module p2)
let tree_of_path namespace p =
tree_of_path namespace (rewrite_double_underscore_paths !printing_env p)
let path ppf p =
!Oprint.out_ident ppf (tree_of_path Other p)
let string_of_path p =
Format.asprintf "%a" path p
let strings_of_paths namespace p =
reset_naming_context ();
let trees = List.map (tree_of_path namespace) p in
List.map (Format.asprintf "%a" !Oprint.out_ident) trees
let () = Env.print_path := path
(* Print a recursive annotation *)
let tree_of_rec = function
| Trec_not -> Orec_not
| Trec_first -> Orec_first
| Trec_next -> Orec_next
(* Print a raw type expression, with sharing *)
let raw_list pr ppf = function
[] -> fprintf ppf "[]"
| a :: l ->
fprintf ppf "@[<1>[%a%t]@]" pr a
(fun ppf -> List.iter (fun x -> fprintf ppf ";@,%a" pr x) l)
let kind_vars = ref []
let kind_count = ref 0
let rec safe_kind_repr v = function
Fvar {contents=Some k} ->
if List.memq k v then "Fvar loop" else
safe_kind_repr (k::v) k
| Fvar r ->
let vid =
try List.assq r !kind_vars
with Not_found ->
let c = incr kind_count; !kind_count in
kind_vars := (r,c) :: !kind_vars;
c
in
Printf.sprintf "Fvar {None}@%d" vid
| Fpresent -> "Fpresent"
| Fabsent -> "Fabsent"
let rec safe_commu_repr v = function
Cok -> "Cok"
| Cunknown -> "Cunknown"
| Clink r ->
if List.memq r v then "Clink loop" else
safe_commu_repr (r::v) !r
let rec safe_repr v = function
{desc = Tlink t} when not (List.memq t v) ->
safe_repr (t::v) t
| t -> t
let rec list_of_memo = function
Mnil -> []
| Mcons (_priv, p, _t1, _t2, rem) -> p :: list_of_memo rem
| Mlink rem -> list_of_memo !rem
let print_name ppf = function
None -> fprintf ppf "None"
| Some name -> fprintf ppf "\"%s\"" name
let string_of_label = function
Nolabel -> ""
| Labelled s -> s
| Optional s -> "?"^s
let visited = ref []
let rec raw_type ppf ty =
let ty = safe_repr [] ty in
if List.memq ty !visited then fprintf ppf "{id=%d}" ty.id else begin
visited := ty :: !visited;
fprintf ppf "@[<1>{id=%d;level=%d;scope=%d;desc=@,%a}@]" ty.id ty.level
ty.scope raw_type_desc ty.desc
end
and raw_type_list tl = raw_list raw_type tl
and raw_type_desc ppf = function
Tvar name -> fprintf ppf "Tvar %a" print_name name
| Tarrow(l,t1,t2,c) ->
fprintf ppf "@[<hov1>Tarrow(\"%s\",@,%a,@,%a,@,%s)@]"
(string_of_label l) raw_type t1 raw_type t2
(safe_commu_repr [] c)
| Ttuple tl ->
fprintf ppf "@[<1>Ttuple@,%a@]" raw_type_list tl
| Tconstr (p, tl, abbrev) ->
fprintf ppf "@[<hov1>Tconstr(@,%a,@,%a,@,%a)@]" path p
raw_type_list tl
(raw_list path) (list_of_memo !abbrev)
| Tobject (t, nm) ->
fprintf ppf "@[<hov1>Tobject(@,%a,@,@[<1>ref%t@])@]" raw_type t
(fun ppf ->
match !nm with None -> fprintf ppf " None"
| Some(p,tl) ->
fprintf ppf "(Some(@,%a,@,%a))" path p raw_type_list tl)
| Tfield (f, k, t1, t2) ->
fprintf ppf "@[<hov1>Tfield(@,%s,@,%s,@,%a,@;<0 -1>%a)@]" f
(safe_kind_repr [] k)
raw_type t1 raw_type t2
| Tnil -> fprintf ppf "Tnil"
| Tlink t -> fprintf ppf "@[<1>Tlink@,%a@]" raw_type t
| Tsubst t -> fprintf ppf "@[<1>Tsubst@,%a@]" raw_type t
| Tunivar name -> fprintf ppf "Tunivar %a" print_name name
| Tpoly (t, tl) ->
fprintf ppf "@[<hov1>Tpoly(@,%a,@,%a)@]"
raw_type t
raw_type_list tl
| Tvariant row ->
fprintf ppf
"@[<hov1>{@[%s@,%a;@]@ @[%s@,%a;@]@ %s%B;@ %s%a;@ @[<1>%s%t@]}@]"
"row_fields="
(raw_list (fun ppf (l, f) ->
fprintf ppf "@[%s,@ %a@]" l raw_field f))
row.row_fields
"row_more=" raw_type row.row_more
"row_closed=" row.row_closed
"row_fixed=" raw_row_fixed row.row_fixed
"row_name="
(fun ppf ->
match row.row_name with None -> fprintf ppf "None"
| Some(p,tl) ->
fprintf ppf "Some(@,%a,@,%a)" path p raw_type_list tl)
| Tpackage (p, _, tl) ->
fprintf ppf "@[<hov1>Tpackage(@,%a@,%a)@]" path p
raw_type_list tl
and raw_row_fixed ppf = function
| None -> fprintf ppf "None"
| Some Types.Fixed_private -> fprintf ppf "Some Fixed_private"
| Some Types.Rigid -> fprintf ppf "Some Rigid"
| Some Types.Univar t -> fprintf ppf "Some(Univar(%a))" raw_type t
| Some Types.Reified p -> fprintf ppf "Some(Reified(%a))" path p
and raw_field ppf = function
Rpresent None -> fprintf ppf "Rpresent None"
| Rpresent (Some t) -> fprintf ppf "@[<1>Rpresent(Some@,%a)@]" raw_type t
| Reither (c,tl,m,e) ->
fprintf ppf "@[<hov1>Reither(%B,@,%a,@,%B,@,@[<1>ref%t@])@]" c
raw_type_list tl m
(fun ppf ->
match !e with None -> fprintf ppf " None"
| Some f -> fprintf ppf "@,@[<1>(%a)@]" raw_field f)
| Rabsent -> fprintf ppf "Rabsent"
let raw_type_expr ppf t =
visited := []; kind_vars := []; kind_count := 0;
raw_type ppf t;
visited := []; kind_vars := []
let () = Btype.print_raw := raw_type_expr
(* Normalize paths *)
type param_subst = Id | Nth of int | Map of int list
let is_nth = function
Nth _ -> true
| _ -> false
let compose l1 = function
| Id -> Map l1
| Map l2 -> Map (List.map (List.nth l1) l2)
| Nth n -> Nth (List.nth l1 n)
let apply_subst s1 tyl =
if tyl = [] then []
(* cf. PR#7543: Typemod.type_package doesn't respect type constructor arity *)
else
match s1 with
Nth n1 -> [List.nth tyl n1]
| Map l1 -> List.map (List.nth tyl) l1
| Id -> tyl
type best_path = Paths of Path.t list | Best of Path.t
(** Short-paths cache: the five mutable variables below implement a one-slot
cache for short-paths
*)
let printing_old = ref Env.empty
let printing_pers = ref Concr.empty
(** {!printing_old} and {!printing_pers} are the keys of the one-slot cache *)
let printing_depth = ref 0
let printing_cont = ref ([] : Env.iter_cont list)
let printing_map = ref Path.Map.empty
(**
- {!printing_map} is the main value stored in the cache.
Note that it is evaluated lazily and its value is updated during printing.
- {!printing_dep} is the current exploration depth of the environment,
it is used to determine whenever the {!printing_map} should be evaluated
further before completing a request.
- {!printing_cont} is the list of continuations needed to evaluate
the {!printing_map} one level further (see also {!Env.run_iter_cont})
*)
let same_type t t' = repr t == repr t'
let rec index l x =
match l with
[] -> raise Not_found
| a :: l -> if x == a then 0 else 1 + index l x
let rec uniq = function
[] -> true
| a :: l -> not (List.memq a l) && uniq l
let rec normalize_type_path ?(cache=false) env p =
try
let (params, ty, _) = Env.find_type_expansion p env in
let params = List.map repr params in
match repr ty with
{desc = Tconstr (p1, tyl, _)} ->
let tyl = List.map repr tyl in
if List.length params = List.length tyl
&& List.for_all2 (==) params tyl
then normalize_type_path ~cache env p1
else if cache || List.length params <= List.length tyl
|| not (uniq tyl) then (p, Id)
else
let l1 = List.map (index params) tyl in
let (p2, s2) = normalize_type_path ~cache env p1 in
(p2, compose l1 s2)
| ty ->
(p, Nth (index params ty))
with
Not_found ->
(Env.normalize_type_path None env p, Id)
let penalty s =
if s <> "" && s.[0] = '_' then
10
else
match find_double_underscore s with
| None -> 1
| Some _ -> 10
let rec path_size = function
Pident id ->
penalty (Ident.name id), -Ident.scope id
| Pdot (p, _) ->
let (l, b) = path_size p in (1+l, b)
| Papply (p1, p2) ->
let (l, b) = path_size p1 in
(l + fst (path_size p2), b)
let same_printing_env env =
let used_pers = Env.used_persistent () in
Env.same_types !printing_old env && Concr.equal !printing_pers used_pers
let set_printing_env env =
printing_env := env;
if !Clflags.real_paths ||
!printing_env == Env.empty ||
same_printing_env env then
()
else begin
(* printf "Reset printing_map@."; *)
printing_old := env;
printing_pers := Env.used_persistent ();
printing_map := Path.Map.empty;
printing_depth := 0;
(* printf "Recompute printing_map.@."; *)
let cont =
Env.iter_types
(fun p (p', _decl) ->
let (p1, s1) = normalize_type_path env p' ~cache:true in
(* Format.eprintf "%a -> %a = %a@." path p path p' path p1 *)
if s1 = Id then
try
let r = Path.Map.find p1 !printing_map in
match !r with
Paths l -> r := Paths (p :: l)
| Best p' -> r := Paths [p; p'] (* assert false *)
with Not_found ->
printing_map := Path.Map.add p1 (ref (Paths [p])) !printing_map)
env in
printing_cont := [cont];
end
let wrap_printing_env env f =
set_printing_env env; reset_naming_context ();
try_finally f ~always:(fun () -> set_printing_env Env.empty)
let wrap_printing_env ~error env f =
if error then Env.without_cmis (wrap_printing_env env) f
else wrap_printing_env env f
let rec lid_of_path = function
Path.Pident id ->
Longident.Lident (Ident.name id)
| Path.Pdot (p1, s) ->
Longident.Ldot (lid_of_path p1, s)
| Path.Papply (p1, p2) ->
Longident.Lapply (lid_of_path p1, lid_of_path p2)
let is_unambiguous path env =
let l = Env.find_shadowed_types path env in
List.exists (Path.same path) l || (* concrete paths are ok *)
match l with
[] -> true
| p :: rem ->
(* allow also coherent paths: *)
let normalize p = fst (normalize_type_path ~cache:true env p) in
let p' = normalize p in
List.for_all (fun p -> Path.same (normalize p) p') rem ||
(* also allow repeatedly defining and opening (for toplevel) *)
let id = lid_of_path p in
List.for_all (fun p -> lid_of_path p = id) rem &&
Path.same p (fst (Env.find_type_by_name id env))
let rec get_best_path r =
match !r with
Best p' -> p'
| Paths [] -> raise Not_found
| Paths l ->
r := Paths [];
List.iter
(fun p ->
(* Format.eprintf "evaluating %a@." path p; *)
match !r with
Best p' when path_size p >= path_size p' -> ()
| _ -> if is_unambiguous p !printing_env then r := Best p)
(* else Format.eprintf "%a ignored as ambiguous@." path p *)
l;
get_best_path r
let best_type_path p =
if !printing_env == Env.empty
then (p, Id)
else if !Clflags.real_paths
then (p, Id)
else
let (p', s) = normalize_type_path !printing_env p in
let get_path () = get_best_path (Path.Map.find p' !printing_map) in
while !printing_cont <> [] &&
try fst (path_size (get_path ())) > !printing_depth with Not_found -> true
do
printing_cont := List.map snd (Env.run_iter_cont !printing_cont);
incr printing_depth;
done;
let p'' = try get_path () with Not_found -> p' in
(* Format.eprintf "%a = %a -> %a@." path p path p' path p''; *)
(p'', s)
(* Print a type expression *)
let names = ref ([] : (type_expr * string) list)
let name_counter = ref 0
let named_vars = ref ([] : string list)
let weak_counter = ref 1
let weak_var_map = ref TypeMap.empty
let named_weak_vars = ref String.Set.empty
let reset_names () = names := []; name_counter := 0; named_vars := []
let add_named_var ty =
match ty.desc with
Tvar (Some name) | Tunivar (Some name) ->
if List.mem name !named_vars then () else
named_vars := name :: !named_vars
| _ -> ()
let name_is_already_used name =
List.mem name !named_vars
|| List.exists (fun (_, name') -> name = name') !names
|| String.Set.mem name !named_weak_vars
let rec new_name () =
let name =
if !name_counter < 26
then String.make 1 (Char.chr(97 + !name_counter))
else String.make 1 (Char.chr(97 + !name_counter mod 26)) ^
Int.to_string(!name_counter / 26) in
incr name_counter;
if name_is_already_used name then new_name () else name
let rec new_weak_name ty () =
let name = "weak" ^ Int.to_string !weak_counter in
incr weak_counter;
if name_is_already_used name then new_weak_name ty ()
else begin
named_weak_vars := String.Set.add name !named_weak_vars;
weak_var_map := TypeMap.add ty name !weak_var_map;
name
end
let name_of_type name_generator t =
(* We've already been through repr at this stage, so t is our representative
of the union-find class. *)
try List.assq t !names with Not_found ->
try TypeMap.find t !weak_var_map with Not_found ->
let name =
match t.desc with
Tvar (Some name) | Tunivar (Some name) ->
(* Some part of the type we've already printed has assigned another
* unification variable to that name. We want to keep the name, so try
* adding a number until we find a name that's not taken. *)
let current_name = ref name in
let i = ref 0 in
while List.exists (fun (_, name') -> !current_name = name') !names do
current_name := name ^ (Int.to_string !i);
i := !i + 1;
done;
!current_name
| _ ->
(* No name available, create a new one *)
name_generator ()
in
(* Exception for type declarations *)
if name <> "_" then names := (t, name) :: !names;
name
let check_name_of_type t = ignore(name_of_type new_name t)
let remove_names tyl =
let tyl = List.map repr tyl in
names := List.filter (fun (ty,_) -> not (List.memq ty tyl)) !names
let visited_objects = ref ([] : type_expr list)
let aliased = ref ([] : type_expr list)
let delayed = ref ([] : type_expr list)
let add_delayed t =
if not (List.memq t !delayed) then delayed := t :: !delayed
let is_aliased ty = List.memq (proxy ty) !aliased
let add_alias ty =
let px = proxy ty in
if not (is_aliased px) then begin
aliased := px :: !aliased;
add_named_var px
end
let aliasable ty =
match ty.desc with
Tvar _ | Tunivar _ | Tpoly _ -> false
| Tconstr (p, _, _) ->
not (is_nth (snd (best_type_path p)))
| _ -> true
let namable_row row =
row.row_name <> None &&
List.for_all
(fun (_, f) ->
match row_field_repr f with
| Reither(c, l, _, _) ->
row.row_closed && if c then l = [] else List.length l = 1
| _ -> true)
row.row_fields
let rec mark_loops_rec visited ty =
let ty = repr ty in
let px = proxy ty in
if List.memq px visited && aliasable ty then add_alias px else
let visited = px :: visited in
match ty.desc with
| Tvar _ -> add_named_var ty
| Tarrow(_, ty1, ty2, _) ->
mark_loops_rec visited ty1; mark_loops_rec visited ty2
| Ttuple tyl -> List.iter (mark_loops_rec visited) tyl
| Tconstr(p, tyl, _) ->
let (_p', s) = best_type_path p in
List.iter (mark_loops_rec visited) (apply_subst s tyl)
| Tpackage (_, _, tyl) ->
List.iter (mark_loops_rec visited) tyl
| Tvariant row ->
if List.memq px !visited_objects then add_alias px else
begin
let row = row_repr row in
if not (static_row row) then
visited_objects := px :: !visited_objects;
match row.row_name with
| Some(_p, tyl) when namable_row row ->
List.iter (mark_loops_rec visited) tyl
| _ ->
iter_row (mark_loops_rec visited) row
end
| Tobject (fi, nm) ->
if List.memq px !visited_objects then add_alias px else
begin
if opened_object ty then
visited_objects := px :: !visited_objects;
begin match !nm with
| None ->
let fields, _ = flatten_fields fi in
List.iter
(fun (_, kind, ty) ->
if field_kind_repr kind = Fpresent then
mark_loops_rec visited ty)
fields
| Some (_, l) ->
List.iter (mark_loops_rec visited) (List.tl l)
end
end
| Tfield(_, kind, ty1, ty2) when field_kind_repr kind = Fpresent ->
mark_loops_rec visited ty1; mark_loops_rec visited ty2
| Tfield(_, _, _, ty2) ->
mark_loops_rec visited ty2
| Tnil -> ()
| Tsubst ty -> mark_loops_rec visited ty
| Tlink _ -> fatal_error "Printtyp.mark_loops_rec (2)"
| Tpoly (ty, tyl) ->
List.iter (fun t -> add_alias t) tyl;
mark_loops_rec visited ty
| Tunivar _ -> add_named_var ty
let mark_loops ty =
normalize_type Env.empty ty;
mark_loops_rec [] ty;;
let reset_loop_marks () =
visited_objects := []; aliased := []; delayed := []
let reset_except_context () =
reset_names (); reset_loop_marks ()
let reset () =
reset_naming_context (); Conflicts.reset ();
reset_except_context ()
let reset_and_mark_loops ty =
reset_except_context (); mark_loops ty
let reset_and_mark_loops_list tyl =
reset_except_context (); List.iter mark_loops tyl
(* Disabled in classic mode when printing an unification error *)
let print_labels = ref true
let rec tree_of_typexp sch ty =
let ty = repr ty in
let px = proxy ty in
if List.mem_assq px !names && not (List.memq px !delayed) then
let mark = is_non_gen sch ty in
let name = name_of_type (if mark then new_weak_name ty else new_name) px in
Otyp_var (mark, name) else
let pr_typ () =
match ty.desc with
| Tvar _ ->
(*let lev =
if is_non_gen sch ty then "/" ^ Int.to_string ty.level else "" in*)
let non_gen = is_non_gen sch ty in
let name_gen = if non_gen then new_weak_name ty else new_name in
Otyp_var (non_gen, name_of_type name_gen ty)
| Tarrow(l, ty1, ty2, _) ->
let lab =
if !print_labels || is_optional l then string_of_label l else ""
in
let t1 =
if is_optional l then
match (repr ty1).desc with
| Tconstr(path, [ty], _)
when Path.same path Predef.path_option ->
tree_of_typexp sch ty
| _ -> Otyp_stuff "<hidden>"
else tree_of_typexp sch ty1 in
Otyp_arrow (lab, t1, tree_of_typexp sch ty2)
| Ttuple tyl ->
Otyp_tuple (tree_of_typlist sch tyl)
| Tconstr(p, tyl, _abbrev) ->
let p', s = best_type_path p in
let tyl' = apply_subst s tyl in
if is_nth s && not (tyl'=[]) then tree_of_typexp sch (List.hd tyl') else
Otyp_constr (tree_of_path Type p', tree_of_typlist sch tyl')
| Tvariant row ->
let row = row_repr row in
let fields =
if row.row_closed then
List.filter (fun (_, f) -> row_field_repr f <> Rabsent)
row.row_fields
else row.row_fields in
let present =
List.filter
(fun (_, f) ->
match row_field_repr f with
| Rpresent _ -> true
| _ -> false)
fields in
let all_present = List.length present = List.length fields in
begin match row.row_name with
| Some(p, tyl) when namable_row row ->
let (p', s) = best_type_path p in
let id = tree_of_path Type p' in
let args = tree_of_typlist sch (apply_subst s tyl) in
let out_variant =
if is_nth s then List.hd args else Otyp_constr (id, args) in
if row.row_closed && all_present then
out_variant
else
let non_gen = is_non_gen sch px in
let tags =
if all_present then None else Some (List.map fst present) in
Otyp_variant (non_gen, Ovar_typ out_variant, row.row_closed, tags)
| _ ->
let non_gen =
not (row.row_closed && all_present) && is_non_gen sch px in
let fields = List.map (tree_of_row_field sch) fields in
let tags =
if all_present then None else Some (List.map fst present) in
Otyp_variant (non_gen, Ovar_fields fields, row.row_closed, tags)
end
| Tobject (fi, nm) ->
tree_of_typobject sch fi !nm
| Tnil | Tfield _ ->
tree_of_typobject sch ty None
| Tsubst ty ->
tree_of_typexp sch ty
| Tlink _ ->
fatal_error "Printtyp.tree_of_typexp"
| Tpoly (ty, []) ->
tree_of_typexp sch ty
| Tpoly (ty, tyl) ->
(*let print_names () =
List.iter (fun (_, name) -> prerr_string (name ^ " ")) !names;
prerr_string "; " in *)
let tyl = List.map repr tyl in
if tyl = [] then tree_of_typexp sch ty else begin
let old_delayed = !delayed in
(* Make the names delayed, so that the real type is
printed once when used as proxy *)
List.iter add_delayed tyl;
let tl = List.map (name_of_type new_name) tyl in
let tr = Otyp_poly (tl, tree_of_typexp sch ty) in
(* Forget names when we leave scope *)
remove_names tyl;
delayed := old_delayed; tr
end
| Tunivar _ ->
Otyp_var (false, name_of_type new_name ty)
| Tpackage (p, n, tyl) ->
let n =
List.map (fun li -> String.concat "." (Longident.flatten li)) n in
Otyp_module (tree_of_path Module_type p, n, tree_of_typlist sch tyl)
in
if List.memq px !delayed then delayed := List.filter ((!=) px) !delayed;
if is_aliased px && aliasable ty then begin
check_name_of_type px;
Otyp_alias (pr_typ (), name_of_type new_name px) end
else pr_typ ()
and tree_of_row_field sch (l, f) =
match row_field_repr f with
| Rpresent None | Reither(true, [], _, _) -> (l, false, [])
| Rpresent(Some ty) -> (l, false, [tree_of_typexp sch ty])
| Reither(c, tyl, _, _) ->
if c (* contradiction: constant constructor with an argument *)
then (l, true, tree_of_typlist sch tyl)
else (l, false, tree_of_typlist sch tyl)
| Rabsent -> (l, false, [] (* actually, an error *))
and tree_of_typlist sch tyl =
List.map (tree_of_typexp sch) tyl
and tree_of_typobject sch fi nm =
begin match nm with
| None ->
let pr_fields fi =
let (fields, rest) = flatten_fields fi in
let present_fields =
List.fold_right
(fun (n, k, t) l ->
match field_kind_repr k with
| Fpresent -> (n, t) :: l
| _ -> l)
fields [] in
let sorted_fields =
List.sort
(fun (n, _) (n', _) -> String.compare n n') present_fields in
tree_of_typfields sch rest sorted_fields in
let (fields, rest) = pr_fields fi in
Otyp_object (fields, rest)
| Some (p, ty :: tyl) ->
let non_gen = is_non_gen sch (repr ty) in
let args = tree_of_typlist sch tyl in
let (p', s) = best_type_path p in
assert (s = Id);
Otyp_class (non_gen, tree_of_path Type p', args)
| _ ->
fatal_error "Printtyp.tree_of_typobject"
end
and is_non_gen sch ty =
sch && is_Tvar ty && ty.level <> generic_level
and tree_of_typfields sch rest = function
| [] ->
let rest =
match rest.desc with
| Tvar _ | Tunivar _ -> Some (is_non_gen sch rest)
| Tconstr _ -> Some false
| Tnil -> None
| _ -> fatal_error "typfields (1)"
in
([], rest)
| (s, t) :: l ->
let field = (s, tree_of_typexp sch t) in
let (fields, rest) = tree_of_typfields sch rest l in
(field :: fields, rest)
let typexp sch ppf ty =
!Oprint.out_type ppf (tree_of_typexp sch ty)
let marked_type_expr ppf ty = typexp false ppf ty
let type_expr ppf ty =
(* [type_expr] is used directly by error message printers,
we mark eventual loops ourself to avoid any misuse and stack overflow *)
reset_and_mark_loops ty;
marked_type_expr ppf ty
and type_sch ppf ty = typexp true ppf ty
and type_scheme ppf ty = reset_and_mark_loops ty; typexp true ppf ty
let type_path ppf p =
let (p', s) = best_type_path p in
let p = if (s = Id) then p' else p in
let t = tree_of_path Type p in
!Oprint.out_ident ppf t
(* Maxence *)
let type_scheme_max ?(b_reset_names=true) ppf ty =
if b_reset_names then reset_names () ;
typexp true ppf ty
(* End Maxence *)
let tree_of_type_scheme ty = reset_and_mark_loops ty; tree_of_typexp true ty
(* Print one type declaration *)
let tree_of_constraints params =
List.fold_right
(fun ty list ->
let ty' = unalias ty in
if proxy ty != proxy ty' then
let tr = tree_of_typexp true ty in
(tr, tree_of_typexp true ty') :: list
else list)
params []
let filter_params tyl =
let params =
List.fold_left
(fun tyl ty ->
let ty = repr ty in
if List.memq ty tyl then Btype.newgenty (Tsubst ty) :: tyl
else ty :: tyl)
[] tyl
in List.rev params
let mark_loops_constructor_arguments = function
| Cstr_tuple l -> List.iter mark_loops l
| Cstr_record l -> List.iter (fun l -> mark_loops l.ld_type) l
let rec tree_of_type_decl id decl =
reset_except_context();
let params = filter_params decl.type_params in
begin match decl.type_manifest with
| Some ty ->
let vars = free_variables ty in
List.iter
(function {desc = Tvar (Some "_")} as ty ->
if List.memq ty vars then ty.desc <- Tvar None
| _ -> ())
params
| None -> ()
end;
List.iter add_alias params;
List.iter mark_loops params;
List.iter check_name_of_type (List.map proxy params);
let ty_manifest =
match decl.type_manifest with
| None -> None
| Some ty ->
let ty =
(* Special hack to hide variant name *)
match repr ty with {desc=Tvariant row} ->
let row = row_repr row in
begin match row.row_name with
Some (Pident id', _) when Ident.same id id' ->
newgenty (Tvariant {row with row_name = None})
| _ -> ty
end
| _ -> ty
in
mark_loops ty;
Some ty
in
begin match decl.type_kind with
| Type_abstract -> ()
| Type_variant cstrs ->
List.iter
(fun c ->
mark_loops_constructor_arguments c.cd_args;
Option.iter mark_loops c.cd_res)
cstrs
| Type_record(l, _rep) ->
List.iter (fun l -> mark_loops l.ld_type) l
| Type_open -> ()
end;
let type_param =
function
| Otyp_var (_, id) -> id
| _ -> "?"
in
let type_defined decl =
let abstr =
match decl.type_kind with
Type_abstract ->
decl.type_manifest = None || decl.type_private = Private
| Type_record _ ->
decl.type_private = Private
| Type_variant tll ->
decl.type_private = Private ||
List.exists (fun cd -> cd.cd_res <> None) tll
| Type_open ->
decl.type_manifest = None
in
let vari =
List.map2
(fun ty v ->
let is_var = is_Tvar (repr ty) in
if abstr || not is_var then
let inj =
decl.type_kind = Type_abstract && Variance.mem Inj v &&
match decl.type_manifest with
| None -> true
| Some ty -> (* only abstract or private row types *)
decl.type_private = Private &&
Btype.is_constr_row ~allow_ident:true (Btype.row_of_type ty)
and (co, cn) = Variance.get_upper v in
(if not cn then Covariant else
if not co then Contravariant else NoVariance),
(if inj then Injective else NoInjectivity)
else (NoVariance, NoInjectivity))
decl.type_params decl.type_variance
in
(Ident.name id,
List.map2 (fun ty cocn -> type_param (tree_of_typexp false ty), cocn)
params vari)
in
let tree_of_manifest ty1 =
match ty_manifest with
| None -> ty1
| Some ty -> Otyp_manifest (tree_of_typexp false ty, ty1)
in
let (name, args) = type_defined decl in
let constraints = tree_of_constraints params in
let ty, priv =
match decl.type_kind with
| Type_abstract ->
begin match ty_manifest with
| None -> (Otyp_abstract, Public)
| Some ty ->
tree_of_typexp false ty, decl.type_private
end
| Type_variant cstrs ->
tree_of_manifest (Otyp_sum (List.map tree_of_constructor cstrs)),
decl.type_private
| Type_record(lbls, _rep) ->
tree_of_manifest (Otyp_record (List.map tree_of_label lbls)),
decl.type_private
| Type_open ->
tree_of_manifest Otyp_open,
decl.type_private
in
{ otype_name = name;
otype_params = args;
otype_type = ty;
otype_private = priv;
otype_immediate = Type_immediacy.of_attributes decl.type_attributes;
otype_unboxed = decl.type_unboxed.unboxed;
otype_cstrs = constraints }
and tree_of_constructor_arguments = function
| Cstr_tuple l -> tree_of_typlist false l
| Cstr_record l -> [ Otyp_record (List.map tree_of_label l) ]
and tree_of_constructor cd =
let name = Ident.name cd.cd_id in
let arg () = tree_of_constructor_arguments cd.cd_args in
match cd.cd_res with
| None -> (name, arg (), None)
| Some res ->
let nm = !names in
names := [];
let ret = tree_of_typexp false res in
let args = arg () in
names := nm;
(name, args, Some ret)
and tree_of_label l =
(Ident.name l.ld_id, l.ld_mutable = Mutable, tree_of_typexp false l.ld_type)
let constructor ppf c =
reset_except_context ();
!Oprint.out_constr ppf (tree_of_constructor c)
let label ppf l =
reset_except_context ();
!Oprint.out_label ppf (tree_of_label l)
let tree_of_type_declaration id decl rs =
Osig_type (tree_of_type_decl id decl, tree_of_rec rs)
let type_declaration id ppf decl =
!Oprint.out_sig_item ppf (tree_of_type_declaration id decl Trec_first)
let constructor_arguments ppf a =
let tys = tree_of_constructor_arguments a in
!Oprint.out_type ppf (Otyp_tuple tys)
(* Print an extension declaration *)
let extension_constructor_args_and_ret_type_subtree ext_args ext_ret_type =
match ext_ret_type with
| None -> (tree_of_constructor_arguments ext_args, None)
| Some res ->
let nm = !names in
names := [];
let ret = tree_of_typexp false res in
let args = tree_of_constructor_arguments ext_args in
names := nm;
(args, Some ret)
let tree_of_extension_constructor id ext es =
reset_except_context ();
let ty_name = Path.name ext.ext_type_path in
let ty_params = filter_params ext.ext_type_params in
List.iter add_alias ty_params;
List.iter mark_loops ty_params;
List.iter check_name_of_type (List.map proxy ty_params);
mark_loops_constructor_arguments ext.ext_args;
Option.iter mark_loops ext.ext_ret_type;
let type_param =
function
| Otyp_var (_, id) -> id
| _ -> "?"
in
let ty_params =
List.map (fun ty -> type_param (tree_of_typexp false ty)) ty_params
in
let name = Ident.name id in
let args, ret =
extension_constructor_args_and_ret_type_subtree
ext.ext_args
ext.ext_ret_type
in
let ext =
{ oext_name = name;
oext_type_name = ty_name;
oext_type_params = ty_params;
oext_args = args;
oext_ret_type = ret;
oext_private = ext.ext_private }
in
let es =
match es with
Text_first -> Oext_first
| Text_next -> Oext_next
| Text_exception -> Oext_exception
in
Osig_typext (ext, es)
let extension_constructor id ppf ext =
!Oprint.out_sig_item ppf (tree_of_extension_constructor id ext Text_first)
let extension_only_constructor id ppf ext =
reset_except_context ();
let name = Ident.name id in
let args, ret =
extension_constructor_args_and_ret_type_subtree
ext.ext_args
ext.ext_ret_type
in
Format.fprintf ppf "@[<hv>%a@]"
!Oprint.out_constr (name, args, ret)
(* Print a value declaration *)
let tree_of_value_description id decl =
(* Format.eprintf "@[%a@]@." raw_type_expr decl.val_type; *)
let id = Ident.name id in
let ty = tree_of_type_scheme decl.val_type in
let vd =
{ oval_name = id;
oval_type = ty;
oval_prims = [];
oval_attributes = [] }
in
let vd =
match decl.val_kind with
| Val_prim p -> Primitive.print p vd
| _ -> vd
in
Osig_value vd
let value_description id ppf decl =
!Oprint.out_sig_item ppf (tree_of_value_description id decl)
(* Print a class type *)
let method_type (_, kind, ty) =
match field_kind_repr kind, repr ty with
Fpresent, {desc=Tpoly(ty, tyl)} -> (ty, tyl)
| _ , ty -> (ty, [])
let tree_of_metho sch concrete csil (lab, kind, ty) =
if lab <> dummy_method then begin
let kind = field_kind_repr kind in
let priv = kind <> Fpresent in
let virt = not (Concr.mem lab concrete) in
let (ty, tyl) = method_type (lab, kind, ty) in
let tty = tree_of_typexp sch ty in
remove_names tyl;
Ocsg_method (lab, priv, virt, tty) :: csil
end
else csil
let rec prepare_class_type params = function
| Cty_constr (_p, tyl, cty) ->
let sty = Ctype.self_type cty in
if List.memq (proxy sty) !visited_objects
|| not (List.for_all is_Tvar params)
|| List.exists (deep_occur sty) tyl
then prepare_class_type params cty
else List.iter mark_loops tyl
| Cty_signature sign ->
let sty = repr sign.csig_self in
(* Self may have a name *)
let px = proxy sty in
if List.memq px !visited_objects then add_alias sty
else visited_objects := px :: !visited_objects;
let (fields, _) =
Ctype.flatten_fields (Ctype.object_fields sign.csig_self)
in
List.iter (fun met -> mark_loops (fst (method_type met))) fields;
Vars.iter (fun _ (_, _, ty) -> mark_loops ty) sign.csig_vars
| Cty_arrow (_, ty, cty) ->
mark_loops ty;
prepare_class_type params cty
let rec tree_of_class_type sch params =
function
| Cty_constr (p', tyl, cty) ->
let sty = Ctype.self_type cty in
if List.memq (proxy sty) !visited_objects
|| not (List.for_all is_Tvar params)
then
tree_of_class_type sch params cty
else
let namespace = Namespace.best_class_namespace p' in
Octy_constr (tree_of_path namespace p', tree_of_typlist true tyl)
| Cty_signature sign ->
let sty = repr sign.csig_self in
let self_ty =
if is_aliased sty then
Some (Otyp_var (false, name_of_type new_name (proxy sty)))
else None
in
let (fields, _) =
Ctype.flatten_fields (Ctype.object_fields sign.csig_self)
in
let csil = [] in
let csil =
List.fold_left
(fun csil (ty1, ty2) -> Ocsg_constraint (ty1, ty2) :: csil)
csil (tree_of_constraints params)
in
let all_vars =
Vars.fold (fun l (m, v, t) all -> (l, m, v, t) :: all) sign.csig_vars []
in
(* Consequence of PR#3607: order of Map.fold has changed! *)
let all_vars = List.rev all_vars in
let csil =
List.fold_left
(fun csil (l, m, v, t) ->
Ocsg_value (l, m = Mutable, v = Virtual, tree_of_typexp sch t)
:: csil)
csil all_vars
in
let csil =
List.fold_left (tree_of_metho sch sign.csig_concr) csil fields
in
Octy_signature (self_ty, List.rev csil)
| Cty_arrow (l, ty, cty) ->
let lab =
if !print_labels || is_optional l then string_of_label l else ""
in
let tr =
if is_optional l then
match (repr ty).desc with
| Tconstr(path, [ty], _) when Path.same path Predef.path_option ->
tree_of_typexp sch ty
| _ -> Otyp_stuff "<hidden>"
else tree_of_typexp sch ty in
Octy_arrow (lab, tr, tree_of_class_type sch params cty)
let class_type ppf cty =
reset ();
prepare_class_type [] cty;
!Oprint.out_class_type ppf (tree_of_class_type false [] cty)
let tree_of_class_param param variance =
(match tree_of_typexp true param with
Otyp_var (_, s) -> s
| _ -> "?"),
if is_Tvar (repr param) then Asttypes.(NoVariance, NoInjectivity)
else variance
let class_variance =
let open Variance in let open Asttypes in
List.map (fun v ->
(if not (mem May_pos v) then Contravariant else
if not (mem May_neg v) then Covariant else NoVariance),
NoInjectivity)
let tree_of_class_declaration id cl rs =
let params = filter_params cl.cty_params in
reset_except_context ();
List.iter add_alias params;
prepare_class_type params cl.cty_type;
let sty = Ctype.self_type cl.cty_type in
List.iter mark_loops params;
List.iter check_name_of_type (List.map proxy params);
if is_aliased sty then check_name_of_type (proxy sty);
let vir_flag = cl.cty_new = None in
Osig_class
(vir_flag, Ident.name id,
List.map2 tree_of_class_param params (class_variance cl.cty_variance),
tree_of_class_type true params cl.cty_type,
tree_of_rec rs)
let class_declaration id ppf cl =
!Oprint.out_sig_item ppf (tree_of_class_declaration id cl Trec_first)
let tree_of_cltype_declaration id cl rs =
let params = List.map repr cl.clty_params in
reset_except_context ();
List.iter add_alias params;
prepare_class_type params cl.clty_type;
let sty = Ctype.self_type cl.clty_type in
List.iter mark_loops params;
List.iter check_name_of_type (List.map proxy params);
if is_aliased sty then check_name_of_type (proxy sty);
let sign = Ctype.signature_of_class_type cl.clty_type in
let virt =
let (fields, _) =
Ctype.flatten_fields (Ctype.object_fields sign.csig_self) in
List.exists
(fun (lab, _, _) ->
not (lab = dummy_method || Concr.mem lab sign.csig_concr))
fields
|| Vars.fold (fun _ (_,vr,_) b -> vr = Virtual || b) sign.csig_vars false
in
Osig_class_type
(virt, Ident.name id,
List.map2 tree_of_class_param params (class_variance cl.clty_variance),
tree_of_class_type true params cl.clty_type,
tree_of_rec rs)
let cltype_declaration id ppf cl =
!Oprint.out_sig_item ppf (tree_of_cltype_declaration id cl Trec_first)
(* Print a module type *)
let wrap_env fenv ftree arg =
(* We save the current value of the short-path cache *)
(* From keys *)
let env = !printing_env in
let old_pers = !printing_pers in
(* to data *)
let old_map = !printing_map in
let old_depth = !printing_depth in
let old_cont = !printing_cont in
set_printing_env (fenv env);
let tree = ftree arg in
if !Clflags.real_paths
|| same_printing_env env then ()
(* our cached key is still live in the cache, and we want to keep all
progress made on the computation of the [printing_map] *)
else begin
(* we restore the snapshotted cache before calling set_printing_env *)
printing_old := env;
printing_pers := old_pers;
printing_depth := old_depth;
printing_cont := old_cont;
printing_map := old_map
end;
set_printing_env env;
tree
let filter_rem_sig item rem =
match item, rem with
| Sig_class _, ctydecl :: tydecl1 :: tydecl2 :: rem ->
([ctydecl; tydecl1; tydecl2], rem)
| Sig_class_type _, tydecl1 :: tydecl2 :: rem ->
([tydecl1; tydecl2], rem)
| _ ->
([], rem)
let dummy =
{
type_params = [];
type_arity = 0;
type_kind = Type_abstract;
type_private = Public;
type_manifest = None;
type_variance = [];
type_separability = [];
type_is_newtype = false;
type_expansion_scope = Btype.lowest_level;
type_loc = Location.none;
type_attributes = [];
type_immediate = Unknown;
type_unboxed = unboxed_false_default_false;
type_uid = Uid.internal_not_actually_unique;
}
let hide ids env = List.fold_right
(fun id -> Env.add_type ~check:false (Ident.rename id) dummy)
ids env
let hide_rec_items = function
| Sig_type(id, _decl, rs, _) ::rem
when rs = Trec_first && not !Clflags.real_paths ->
let rec get_ids = function
Sig_type (id, _, Trec_next, _) :: rem ->
id :: get_ids rem
| _ -> []
in
let ids = id :: get_ids rem in
set_printing_env
(hide ids !printing_env)
| _ -> ()
let recursive_sigitem = function
| Sig_class(id,_,rs,_) -> Some(id,rs,3)
| Sig_class_type (id,_,rs,_) -> Some(id,rs,2)
| Sig_type(id, _, rs, _)
| Sig_module(id, _, _, rs, _) -> Some (id,rs,0)
| _ -> None
let skip k l = snd (Misc.Stdlib.List.split_at k l)
let protect_rec_items items =
let rec get_ids recs = function
| [] -> []
| item :: rem -> match recursive_sigitem item with
| Some (id, r, k ) when r = recs -> id :: get_ids Trec_next (skip k rem)
| _ -> [] in
List.iter Naming_context.add_protected (get_ids Trec_first items)
let stop_type_group env =
Naming_context.reset_protected ();
set_printing_env env
let still_in_type_group env' in_type_group item =
match in_type_group, recursive_sigitem item with
| true, Some (_,Trec_next,_) -> true
| _, Some (_, (Trec_not | Trec_first),_) ->
stop_type_group env' ; true
| _ -> stop_type_group env'; false
let rec tree_of_modtype ?(ellipsis=false) = function
| Mty_ident p ->
Omty_ident (tree_of_path Module_type p)
| Mty_signature sg ->
Omty_signature (if ellipsis then [Osig_ellipsis]
else tree_of_signature sg)
| Mty_functor(param, ty_res) ->
let param, res =
match param with
| Unit -> None, tree_of_modtype ~ellipsis ty_res
| Named (param, ty_arg) ->
let name, env =
match param with
| None -> None, fun env -> env
| Some id ->
Some (Ident.name id),
Env.add_module ~arg:true id Mp_present ty_arg
in
Some (name, tree_of_modtype ~ellipsis:false ty_arg),
wrap_env env (tree_of_modtype ~ellipsis) ty_res
in
Omty_functor (param, res)
| Mty_alias p ->
Omty_alias (tree_of_path Module p)
and tree_of_signature sg =
wrap_env (fun env -> env) (tree_of_signature_rec !printing_env false) sg
and tree_of_signature_rec env' in_type_group = function
[] -> stop_type_group env'; []
| item :: rem as items ->
let in_type_group = still_in_type_group env' in_type_group item in
let (sg, rem) = filter_rem_sig item rem in
hide_rec_items items;
protect_rec_items items;
reset_naming_context ();
let trees = trees_of_sigitem item in
let env' = Env.add_signature (item :: sg) env' in
trees @ tree_of_signature_rec env' in_type_group rem
and trees_of_sigitem = function
| Sig_value(id, decl, _) ->
[tree_of_value_description id decl]
| Sig_type(id, _, _, _) when is_row_name (Ident.name id) ->
[]
| Sig_type(id, decl, rs, _) ->
[tree_of_type_declaration id decl rs]
| Sig_typext(id, ext, es, _) ->
[tree_of_extension_constructor id ext es]
| Sig_module(id, _, md, rs, _) ->
let ellipsis =
List.exists (function
| Parsetree.{attr_name = {txt="..."}; attr_payload = PStr []} -> true
| _ -> false)
md.md_attributes in
[tree_of_module id md.md_type rs ~ellipsis]
| Sig_modtype(id, decl, _) ->
[tree_of_modtype_declaration id decl]
| Sig_class(id, decl, rs, _) ->
[tree_of_class_declaration id decl rs]
| Sig_class_type(id, decl, rs, _) ->
[tree_of_cltype_declaration id decl rs]
and tree_of_modtype_declaration id decl =
let mty =
match decl.mtd_type with
| None -> Omty_abstract
| Some mty -> tree_of_modtype mty
in
Osig_modtype (Ident.name id, mty)
and tree_of_module id ?ellipsis mty rs =
Osig_module (Ident.name id, tree_of_modtype ?ellipsis mty, tree_of_rec rs)
let modtype ppf mty = !Oprint.out_module_type ppf (tree_of_modtype mty)
let modtype_declaration id ppf decl =
!Oprint.out_sig_item ppf (tree_of_modtype_declaration id decl)
(* For the toplevel: merge with tree_of_signature? *)
(* Refresh weak variable map in the toplevel *)
let refresh_weak () =
let refresh t name (m,s) =
if is_non_gen true (repr t) then
begin
TypeMap.add t name m,
String.Set.add name s
end
else m, s in
let m, s =
TypeMap.fold refresh !weak_var_map (TypeMap.empty ,String.Set.empty) in
named_weak_vars := s;
weak_var_map := m
let print_items showval env x =
refresh_weak();
reset_naming_context ();
Conflicts.reset ();
let rec print showval in_type_group env = function
| [] -> stop_type_group env; []
| item :: rem as items ->
let in_type_group = still_in_type_group env in_type_group item in
let (sg, rem) = filter_rem_sig item rem in
hide_rec_items items;
protect_rec_items items;
reset_naming_context ();
let trees = trees_of_sigitem item in
List.map (fun d -> (d, showval env item)) trees @
print showval in_type_group (Env.add_signature (item :: sg) env) rem in
print showval false env x
(* Print a signature body (used by -i when compiling a .ml) *)
let print_signature ppf tree =
fprintf ppf "@[<v>%a@]" !Oprint.out_signature tree
let signature ppf sg =
fprintf ppf "%a" print_signature (tree_of_signature sg)
(* Print a signature body (used by -i when compiling a .ml) *)
let printed_signature sourcefile ppf sg =
(* we are tracking any collision event for warning 63 *)
Conflicts.reset ();
reset_naming_context ();
let t = tree_of_signature sg in
if Warnings.(is_active @@ Erroneous_printed_signature "")
&& Conflicts.exists ()
then begin
let conflicts = Format.asprintf "%t" Conflicts.print_explanations in
Location.prerr_warning (Location.in_file sourcefile)
(Warnings.Erroneous_printed_signature conflicts);
Warnings.check_fatal ()
end;
fprintf ppf "%a" print_signature t
(* Print an unification error *)
let same_path t t' =
let t = repr t and t' = repr t' in
t == t' ||
match t.desc, t'.desc with
Tconstr(p,tl,_), Tconstr(p',tl',_) ->
let (p1, s1) = best_type_path p and (p2, s2) = best_type_path p' in
begin match s1, s2 with
Nth n1, Nth n2 when n1 = n2 -> true
| (Id | Map _), (Id | Map _) when Path.same p1 p2 ->
let tl = apply_subst s1 tl and tl' = apply_subst s2 tl' in
List.length tl = List.length tl' &&
List.for_all2 same_type tl tl'
| _ -> false
end
| _ ->
false
type 'a diff = Same of 'a | Diff of 'a * 'a
let trees_of_type_expansion (t,t') =
if same_path t t'
then begin add_delayed (proxy t); Same (tree_of_typexp false t) end
else
let t' = if proxy t == proxy t' then unalias t' else t' in
(* beware order matter due to side effect,
e.g. when printing object types *)
let first = tree_of_typexp false t in
let second = tree_of_typexp false t' in
if first = second then Same first
else Diff(first,second)
let type_expansion ppf = function
| Same t -> !Oprint.out_type ppf t
| Diff(t,t') ->
fprintf ppf "@[<2>%a@ =@ %a@]" !Oprint.out_type t !Oprint.out_type t'
module Trace = Ctype.Unification_trace
let trees_of_trace = List.map (Trace.map_diff trees_of_type_expansion)
let trees_of_type_path_expansion (tp,tp') =
if Path.same tp tp' then Same(tree_of_path Type tp) else
Diff(tree_of_path Type tp, tree_of_path Type tp')
let type_path_expansion ppf = function
| Same p -> !Oprint.out_ident ppf p
| Diff(p,p') ->
fprintf ppf "@[<2>%a@ =@ %a@]"
!Oprint.out_ident p
!Oprint.out_ident p'
let rec trace fst txt ppf = function
| {Trace.got; expected} :: rem ->
if not fst then fprintf ppf "@,";
fprintf ppf "@[Type@;<1 2>%a@ %s@;<1 2>%a@] %a"
type_expansion got txt type_expansion expected
(trace false txt) rem
| _ -> ()
type printing_status =
| Discard
| Keep
| Optional_refinement
(** An [Optional_refinement] printing status is attributed to trace
elements that are focusing on a new subpart of a structural type.
Since the whole type should have been printed earlier in the trace,
we only print those elements if they are the last printed element
of a trace, and there is no explicit explanation for the
type error.
*)
let printing_status = function
| Trace.(Diff { got=t1, t1'; expected=t2, t2'}) ->
if is_constr_row ~allow_ident:true t1'
|| is_constr_row ~allow_ident:true t2'
then Discard
else if same_path t1 t1' && same_path t2 t2' then Optional_refinement
else Keep
| _ -> Keep
(** Flatten the trace and remove elements that are always discarded
during printing *)
let prepare_trace f tr =
let clean_trace x l = match printing_status x with
| Keep -> x :: l
| Optional_refinement when l = [] -> [x]
| Optional_refinement | Discard -> l
in
match Trace.flatten f tr with
| [] -> []
| elt :: rem -> (* the first element is always kept *)
elt :: List.fold_right clean_trace rem []
(** Keep elements that are not [Diff _ ] and take the decision
for the last element, require a prepared trace *)
let rec filter_trace keep_last = function
| [] -> []
| [Trace.Diff d as elt] when printing_status elt = Optional_refinement ->
if keep_last then [d] else []
| Trace.Diff d :: rem -> d :: filter_trace keep_last rem
| _ :: rem -> filter_trace keep_last rem
let type_path_list =
Format.pp_print_list ~pp_sep:(fun ppf () -> Format.pp_print_break ppf 2 0)
type_path_expansion
(* Hide variant name and var, to force printing the expanded type *)
let hide_variant_name t =
match repr t with
| {desc = Tvariant row} as t when (row_repr row).row_name <> None ->
newty2 t.level
(Tvariant {(row_repr row) with row_name = None;
row_more = newvar2 (row_more row).level})
| _ -> t
let prepare_expansion (t, t') =
let t' = hide_variant_name t' in
mark_loops t;
if not (same_path t t') then mark_loops t';
(t, t')
let may_prepare_expansion compact (t, t') =
match (repr t').desc with
Tvariant _ | Tobject _ when compact ->
mark_loops t; (t, t)
| _ -> prepare_expansion (t, t')
let print_tag ppf = fprintf ppf "`%s"
let print_tags =
let comma ppf () = Format.fprintf ppf ",@ " in
Format.pp_print_list ~pp_sep:comma print_tag
let is_unit env ty =
match (Ctype.expand_head env ty).desc with
| Tconstr (p, _, _) -> Path.same p Predef.path_unit
| _ -> false
let unifiable env ty1 ty2 =
let snap = Btype.snapshot () in
let res =
try Ctype.unify env ty1 ty2; true
with Unify _ -> false
in
Btype.backtrack snap;
res
let explanation_diff env t3 t4 : (Format.formatter -> unit) option =
match t3.desc, t4.desc with
| Tarrow (_, ty1, ty2, _), _
when is_unit env ty1 && unifiable env ty2 t4 ->
Some (fun ppf ->
fprintf ppf
"@,@[Hint: Did you forget to provide `()' as argument?@]")
| _, Tarrow (_, ty1, ty2, _)
when is_unit env ty1 && unifiable env t3 ty2 ->
Some (fun ppf ->
fprintf ppf
"@,@[Hint: Did you forget to wrap the expression using \
`fun () ->'?@]")
| _ ->
None
let print_pos ppf = function
| Trace.First -> fprintf ppf "first"
| Trace.Second -> fprintf ppf "second"
let explain_fixed_row_case ppf = function
| Trace.Cannot_be_closed -> Format.fprintf ppf "it cannot be closed"
| Trace.Cannot_add_tags tags ->
Format.fprintf ppf "it may not allow the tag(s) %a"
print_tags tags
let explain_fixed_row pos expl = match expl with
| Types.Fixed_private ->
dprintf "The %a variant type is private" print_pos pos
| Types.Univar x ->
dprintf "The %a variant type is bound to the universal type variable %a"
print_pos pos type_expr x
| Types.Reified p ->
let p = tree_of_path Type p in
dprintf "The %a variant type is bound to %a" print_pos pos
!Oprint.out_ident p
| Types.Rigid -> ignore
let explain_variant = function
| Trace.No_intersection ->
Some(dprintf "@,These two variant types have no intersection")
| Trace.No_tags(pos,fields) -> Some(
dprintf
"@,@[The %a variant type does not allow tag(s)@ @[<hov>%a@]@]"
print_pos pos
print_tags (List.map fst fields)
)
| Trace.Incompatible_types_for s ->
Some(dprintf "@,Types for tag `%s are incompatible" s)
| Trace.Fixed_row (pos, k, (Univar _ | Reified _ | Fixed_private as e)) ->
Some (
dprintf "@,@[%t,@ %a@]" (explain_fixed_row pos e)
explain_fixed_row_case k
)
| Trace.Fixed_row (_,_, Rigid) ->
(* this case never happens *)
None
let explain_escape intro prev ctx e =
let pre = match ctx with
| Some ctx -> dprintf "@[%t@;<1 2>%a@]" intro type_expr ctx
| None -> match e, prev with
| Trace.Univ _, Some(Trace.Incompatible_fields {name; diff}) ->
dprintf "@,@[The method %s has type@ %a,@ \
but the expected method type was@ %a@]" name
type_expr diff.Trace.got type_expr diff.Trace.expected
| _ -> ignore in
match e with
| Trace.Univ u -> Some(
dprintf "%t@,The universal variable %a would escape its scope"
pre type_expr u)
| Trace.Constructor p -> Some(
dprintf
"%t@,@[The type constructor@;<1 2>%a@ would escape its scope@]"
pre path p
)
| Trace.Module_type p -> Some(
dprintf
"%t@,@[The module type@;<1 2>%a@ would escape its scope@]"
pre path p
)
| Trace.Equation (_,t) -> Some(
dprintf "%t @,@[<hov>This instance of %a is ambiguous:@ %s@]"
pre type_expr t
"it would escape the scope of its equation"
)
| Trace.Self ->
Some (dprintf "%t@,Self type cannot escape its class" pre)
let explain_object = function
| Trace.Self_cannot_be_closed ->
Some (dprintf "@,Self type cannot be unified with a closed object type")
| Trace.Missing_field (pos,f) ->
Some(dprintf "@,@[The %a object type has no method %s@]" print_pos pos f)
| Trace.Abstract_row pos -> Some(
dprintf
"@,@[The %a object type has an abstract row, it cannot be closed@]"
print_pos pos
)
let explanation intro prev env = function
| Trace.Diff { Trace.got = _, s; expected = _,t } -> explanation_diff env s t
| Trace.Escape {kind;context} -> explain_escape intro prev context kind
| Trace.Incompatible_fields { name; _ } ->
Some(dprintf "@,Types for method %s are incompatible" name)
| Trace.Variant v -> explain_variant v
| Trace.Obj o -> explain_object o
| Trace.Rec_occur(x,y) ->
reset_and_mark_loops y;
Some(dprintf "@,@[<hov>The type variable %a occurs inside@ %a@]"
marked_type_expr x marked_type_expr y)
let mismatch intro env trace =
Trace.explain trace (fun ~prev h -> explanation intro prev env h)
let explain mis ppf =
match mis with
| None -> ()
| Some explain -> explain ppf
let warn_on_missing_def env ppf t =
match t.desc with
| Tconstr (p,_,_) ->
begin
try
ignore(Env.find_type p env : Types.type_declaration)
with Not_found ->
fprintf ppf
"@,@[%a is abstract because no corresponding cmi file was found \
in path.@]" path p
end
| _ -> ()
let prepare_expansion_head empty_tr = function
| Trace.Diff d ->
Some(Trace.map_diff (may_prepare_expansion empty_tr) d)
| _ -> None
let head_error_printer txt_got txt_but = function
| None -> ignore
| Some d ->
let d = Trace.map_diff trees_of_type_expansion d in
dprintf "%t@;<1 2>%a@ %t@;<1 2>%a"
txt_got type_expansion d.Trace.got
txt_but type_expansion d.Trace.expected
let warn_on_missing_defs env ppf = function
| None -> ()
| Some {Trace.got=te1,_; expected=te2,_ } ->
warn_on_missing_def env ppf te1;
warn_on_missing_def env ppf te2
let unification_error env tr txt1 ppf txt2 ty_expect_explanation =
reset ();
let tr = prepare_trace (fun t t' -> t, hide_variant_name t') tr in
let mis = mismatch txt1 env tr in
match tr with
| [] -> assert false
| elt :: tr ->
try
print_labels := not !Clflags.classic;
let tr = filter_trace (mis = None) tr in
let head = prepare_expansion_head (tr=[]) elt in
let tr = List.map (Trace.map_diff prepare_expansion) tr in
let head_error = head_error_printer txt1 txt2 head in
let tr = trees_of_trace tr in
fprintf ppf
"@[<v>\
@[%t%t@]%a%t\
@]"
head_error
ty_expect_explanation
(trace false "is not compatible with type") tr
(explain mis);
if env <> Env.empty
then warn_on_missing_defs env ppf head;
Conflicts.print_explanations ppf;
print_labels := true
with exn ->
print_labels := true;
raise exn
let report_unification_error ppf env tr
?(type_expected_explanation = fun _ -> ())
txt1 txt2 =
wrap_printing_env env (fun () -> unification_error env tr txt1 ppf txt2
type_expected_explanation)
~error:true
;;
(** [trace] requires the trace to be prepared *)
let trace fst keep_last txt ppf tr =
print_labels := not !Clflags.classic;
try match tr with
| elt :: tr' ->
let elt = match elt with
| Trace.Diff diff -> [Trace.map_diff trees_of_type_expansion diff]
| _ -> [] in
let tr =
trees_of_trace
@@ List.map (Trace.map_diff prepare_expansion)
@@ filter_trace keep_last tr' in
if fst then trace fst txt ppf (elt @ tr)
else trace fst txt ppf tr;
print_labels := true
| _ -> ()
with exn ->
print_labels := true;
raise exn
let report_subtyping_error ppf env tr1 txt1 tr2 =
wrap_printing_env ~error:true env (fun () ->
reset ();
let tr1 = prepare_trace (fun t t' -> prepare_expansion (t, t')) tr1 in
let tr2 = prepare_trace (fun t t' -> prepare_expansion (t, t')) tr2 in
let keep_first = match tr2 with
| Trace.[Obj _ | Variant _ | Escape _ ] | [] -> true
| _ -> false in
fprintf ppf "@[<v>%a" (trace true keep_first txt1) tr1;
if tr2 = [] then fprintf ppf "@]" else
let mis = mismatch (dprintf "Within this type") env tr2 in
fprintf ppf "%a%t%t@]"
(trace false (mis = None) "is not compatible with type") tr2
(explain mis)
Conflicts.print_explanations
)
let report_ambiguous_type_error ppf env tp0 tpl txt1 txt2 txt3 =
wrap_printing_env ~error:true env (fun () ->
reset ();
let tp0 = trees_of_type_path_expansion tp0 in
match tpl with
[] -> assert false
| [tp] ->
fprintf ppf
"@[%t@;<1 2>%a@ \
%t@;<1 2>%a\
@]"
txt1 type_path_expansion (trees_of_type_path_expansion tp)
txt3 type_path_expansion tp0
| _ ->
fprintf ppf
"@[%t@;<1 2>@[<hv>%a@]\
@ %t@;<1 2>%a\
@]"
txt2 type_path_list (List.map trees_of_type_path_expansion tpl)
txt3 type_path_expansion tp0)
(* Adapt functions to exposed interface *)
let tree_of_path = tree_of_path Other
let tree_of_modtype = tree_of_modtype ~ellipsis:false
let type_expansion ty ppf ty' =
type_expansion ppf (trees_of_type_expansion (ty,ty'))
let tree_of_type_declaration id td rs =
Naming_context.with_hidden id ( (* for disambiguation *)
wrap_env (hide [id]) (* for short-path *)
(fun () -> tree_of_type_declaration id td rs)
)