ocaml/typing/printtyp.ml

597 lines
16 KiB
OCaml

(***********************************************************************)
(* *)
(* Objective Caml *)
(* *)
(* Xavier Leroy and Jerome Vouillon, projet Cristal, INRIA Rocquencourt*)
(* *)
(* Copyright 1996 Institut National de Recherche en Informatique et *)
(* Automatique. Distributed only by permission. *)
(* *)
(***********************************************************************)
(* $Id$ *)
(* Printing functions *)
open Misc
open Ctype
open Format
open Longident
open Path
open Asttypes
open Types
open Btype
(* Print a long identifier *)
let rec longident = function
Lident s -> print_string s
| Ldot(p, s) -> longident p; print_string "."; print_string s
| Lapply(p1, p2) ->
longident p1; print_string "("; longident p2; print_string ")"
(* Print an identifier *)
let ident id =
print_string(Ident.name id)
(* Print a path *)
let ident_pervasive = Ident.create_persistent "Pervasives"
let rec path = function
Pident id ->
ident id
| Pdot(Pident id, s, pos) when Ident.same id ident_pervasive ->
print_string s
| Pdot(p, s, pos) ->
path p; print_string "."; print_string s
| Papply(p1, p2) ->
path p1; print_string "("; path p2; print_string ")"
(* Print a type expression *)
let names = ref ([] : (type_expr * string) list)
let name_counter = ref 0
let reset_names () = names := []; name_counter := 0
let 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)) ^
string_of_int(!name_counter / 26)
in
incr name_counter;
name
let name_of_type t =
try List.assq t !names with Not_found ->
let name = new_name () in
names := (t, name) :: !names;
name
let rec list_removeq a =
function
[] ->
[]
| (b, _) as e::l ->
if a == b then l else e::list_removeq a l
let remove_name_of_type t =
names := list_removeq t !names
let visited_objects = ref ([] : type_expr list)
let aliased = ref ([] : type_expr list)
let rec mark_loops_rec visited ty =
let ty = repr ty in
if List.memq ty visited then begin
if not (List.memq ty !aliased) then
aliased := ty :: !aliased
end else
let visited = ty :: visited in
match ty.desc with
Tvar -> ()
| Tarrow(ty1, ty2) ->
mark_loops_rec visited ty1; mark_loops_rec visited ty2
| Ttuple tyl -> List.iter (mark_loops_rec visited) tyl
| Tconstr(_, tyl, _) ->
List.iter (mark_loops_rec visited) tyl
| Tobject (fi, nm) ->
if List.memq ty !visited_objects then begin
if not (List.memq ty !aliased) then
aliased := ty :: !aliased
end else begin
if opened_object ty then
visited_objects := ty :: !visited_objects;
let name =
match !nm with
None -> None
| Some (n, v::l) ->
let v' = repr v in
begin match v'.desc with
Tvar -> Some (n, v'::l)
| _ -> None
end
| _ ->
fatal_error "Printtyp.mark_loops_rec"
in
nm := name;
begin match !nm with
None ->
mark_loops_rec visited fi
| Some (_, l) ->
List.iter (mark_loops_rec visited) 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 -> ()
| Tlink _ -> fatal_error "Printtyp.mark_loops_rec (2)"
let mark_loops ty = mark_loops_rec [] ty
let reset_loop_marks () =
visited_objects := []; aliased := []
let reset () =
reset_names (); reset_loop_marks ()
let rec typexp sch prio0 ty =
let ty = repr ty in
try
List.assq ty !names;
if (ty.desc = Tvar) && sch && (ty.level <> generic_level)
then print_string "'_"
else print_string "'";
print_string (name_of_type ty)
with Not_found ->
let alias = List.memq ty !aliased in
if alias then begin
name_of_type ty;
if prio0 >= 1 then begin open_box 1; print_string "(" end
else open_box 0
end;
let prio = if alias then 0 else prio0 in
begin match ty.desc with
Tvar ->
if (not sch) or ty.level = generic_level
then print_string "'"
else print_string "'_";
print_string(name_of_type ty)
| Tarrow(ty1, ty2) ->
if prio >= 2 then begin open_box 1; print_string "(" end
else open_box 0;
typexp sch 2 ty1;
print_string " ->"; print_space();
typexp sch 1 ty2;
if prio >= 2 then print_string ")";
close_box()
| Ttuple tyl ->
if prio >= 3 then begin open_box 1; print_string "(" end
else open_box 0;
typlist sch 3 " *" tyl;
if prio >= 3 then print_string ")";
close_box()
| Tconstr(p, tyl, abbrev) ->
open_box 0;
begin match tyl with
[] -> ()
| [ty1] ->
typexp sch 3 ty1; print_space()
| tyl ->
open_box 1; print_string "("; typlist sch 0 "," tyl;
print_string ")"; close_box(); print_space()
end;
path p;
close_box()
| Tobject (fi, nm) ->
typobject sch ty fi nm
(*
| Tfield _ -> typobject sch ty ty (ref None)
| Tnil -> typobject sch ty ty (ref None)
*)
| _ ->
fatal_error "Printtyp.typexp"
end;
if alias then begin
print_string " as ";
print_string "'";
print_string (name_of_type ty);
if not (opened_object ty) then
remove_name_of_type ty;
if prio0 >= 1 then print_string ")";
close_box()
end
(* ; print_string "["; print_int ty.level; print_string "]" *)
and typlist sch prio sep = function
[] -> ()
| [ty] -> typexp sch prio ty
| ty::tyl ->
typexp sch prio ty; print_string sep; print_space();
typlist sch prio sep tyl
and typobject sch ty fi nm =
begin match !nm with
None ->
open_box 2;
print_string "< ";
(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
typfields sch rest present_fields);
print_string " >";
close_box ()
| Some (p, {desc = Tvar}::tyl) ->
open_box 0;
begin match tyl with
[] -> ()
| [ty1] ->
typexp sch 3 ty1; print_space()
| tyl ->
open_box 1; print_string "("; typlist sch 0 "," tyl;
print_string ")"; close_box(); print_space()
end;
if sch & ty.level <> generic_level then
print_string "_";
print_string "#";
path p;
close_box()
| _ ->
fatal_error "Printtyp.typobject"
end
and typfields sch rest =
function
[] ->
begin match rest.desc with
Tvar -> if sch & rest.level <> generic_level then
print_string "_";
print_string ".."
| Tnil -> ()
| _ -> fatal_error "typfields (1)"
end
| [(s, t)] ->
print_string s;
print_string " : ";
typexp sch 0 t;
begin match rest.desc with
Tvar -> print_string ";"; print_space ()
| Tnil -> ()
| _ -> fatal_error "typfields (2)"
end;
typfields sch rest []
| (s, t)::l ->
print_string s;
print_string " : ";
typexp sch 0 t;
print_string ";"; print_space ();
typfields sch rest l
let type_expr ty =
typexp false 0 ty
and type_sch ty =
typexp true 0 ty
and type_scheme ty =
reset(); mark_loops ty; typexp true 0 ty
(* Print one type declaration *)
let constrain ty =
let ty' = unalias ty in
if ty != ty' then begin
print_space ();
open_box 2;
print_string "constraint ";
type_sch ty;
print_string " =";
print_space();
type_sch ty';
close_box()
end
let rec type_decl kwd id decl =
reset();
let params = List.map repr decl.type_params in
aliased := params @ !aliased;
List.iter mark_loops params;
List.iter (fun x -> name_of_type x; ()) params;
begin match decl.type_manifest with
None -> ()
| Some ty -> mark_loops ty
end;
begin match decl.type_kind with
Type_abstract -> ()
| Type_variant [] -> ()
| Type_variant cstrs ->
List.iter (fun (_, args) -> List.iter mark_loops args) cstrs
| Type_record (lbl1 :: lbls as l) ->
List.iter (fun (_, _, ty) -> mark_loops ty) l
| _ -> assert false
end;
open_hvbox 2;
print_string kwd;
type_expr {desc = Tconstr(Pident id, params, ref Mnil);
level = generic_level};
begin match decl.type_manifest with
None -> ()
| Some ty ->
print_string " ="; print_space(); type_expr ty
end;
begin match decl.type_kind with
Type_abstract -> ()
| Type_variant [] -> ()
(* A fatal error actually, except when printing type exn... *)
| Type_variant cstrs ->
print_string " =";
List.iter
(fun cstr -> print_space(); print_string "| "; constructor cstr)
cstrs
| Type_record (lbl1 :: lbls as l) ->
print_string " ="; print_space();
print_string "{ "; label lbl1;
List.iter
(fun lbl -> print_string ";"; print_break 1 2; label lbl)
lbls;
print_string " }"
| _ -> assert false
end;
List.iter constrain params;
close_box()
and constructor (name, args) =
print_string name;
match args with
[] -> ()
| _ -> print_string " of ";
open_box 2; typlist false 3 " *" args; close_box()
and label (name, mut, arg) =
begin match mut with
Immutable -> ()
| Mutable -> print_string "mutable "
end;
print_string name;
print_string ": ";
type_expr arg
let type_declaration id decl = type_decl "type " id decl
(* Print an exception declaration *)
let exception_declaration id decl =
print_string "exception "; constructor (Ident.name id, decl)
(* Print a value declaration *)
let value_description id decl =
open_box 2;
print_string (if decl.val_kind = Val_reg then "val " else "external ");
ident id; print_string " :"; print_space();
type_scheme decl.val_type;
begin match decl.val_kind with
Val_prim p ->
print_space(); print_string "= "; Primitive.print_description p
| _ -> ()
end;
close_box()
(* Print a class type *)
let class_arg arg =
print_space ();
open_box 1; print_string "(";
type_sch arg;
print_string ")"; close_box ()
let class_var l (m, t) =
print_space ();
open_box 2;
print_string "val ";
begin match m with
Immutable -> ()
| Mutable -> print_string "mutable "
end;
print_string l;
print_string " :";
print_space();
type_sch t;
close_box()
let metho public concrete lab ty =
print_space ();
open_box 2;
if Concr.mem lab concrete then print_string "method "
else print_string "virtual ";
if not (List.mem_assoc lab public) then print_string "protected ";
print_string lab;
print_string " :";
print_space ();
type_sch ty;
close_box ()
let methods_of_type ty =
match (repr ty).desc with
Tobject (m, _) -> m
| _ -> fatal_error "Printtyp.methods_of_type"
let rec list_public_methods ty =
let (fields, _) = flatten_fields ty in
List.map (function (m, _, t) -> (m, t)) fields
let class_type id cl_ty =
let self = repr cl_ty.cty_self in
let params = List.map repr cl_ty.cty_params in
let args = cl_ty.cty_args in
let vars = cl_ty.cty_vars in
reset ();
(* Self may have a name *)
visited_objects := self :: !visited_objects;
aliased := params @ !aliased;
begin match self.desc with
Tobject (fi, _) -> mark_loops fi
| _ -> fatal_error "Printtyp.class_type"
end;
List.iter mark_loops params;
List.iter mark_loops args;
Vars.iter (fun _ (_, ty) -> mark_loops ty) vars;
Meths.iter (fun _ ty -> mark_loops ty) cl_ty.cty_meths;
List.iter (fun x -> name_of_type x; ()) params;
open_hvbox 2;
open_box 0;
print_string "class ";
if cl_ty.cty_new = None then
print_string "virtual ";
if not (opened_object self) then
print_string "closed ";
type_sch {desc = Tconstr(Pident id, params, ref Mnil); level = 0};
if List.memq self !aliased then
(name_of_type self; ());
List.iter class_arg args;
if List.memq self !aliased then begin
print_string " : ";
print_string "'";
print_string (name_of_type self)
end;
print_string " =";
close_box ();
List.iter constrain params;
Vars.iter class_var vars;
let public_methods = list_public_methods (methods_of_type self) in
let methods =
List.fold_left (fun m (lab, ty) -> Meths.add lab ty m)
cl_ty.cty_meths public_methods
in
Meths.iter (metho public_methods cl_ty.cty_concr) methods;
print_break 1 (-2);
print_string "end";
close_box()
(* Print a module type *)
let rec modtype = function
Tmty_ident p ->
path p
| Tmty_signature sg ->
open_hvbox 2;
print_string "sig"; signature_body true sg;
print_break 1 (-2); print_string "end";
close_box()
| Tmty_functor(param, ty_arg, ty_res) ->
open_box 2;
print_string "functor"; print_cut();
print_string "("; ident param; print_string " : ";
modtype ty_arg;
print_string ") ->"; print_space();
modtype ty_res;
close_box()
and signature_body spc = function
[] -> ()
| item :: rem ->
if spc then print_space();
let cont =
match item with
Tsig_value(id, decl) ->
value_description id decl; rem
| Tsig_type(id, decl) ->
type_declaration id decl;
let rec more_type_declarations = function
Tsig_type(id, decl) :: rem ->
print_space();
type_decl "and " id decl;
more_type_declarations rem
| rem -> rem in
more_type_declarations rem
| Tsig_exception(id, decl) ->
exception_declaration id decl; rem
| Tsig_module(id, mty) ->
open_box 2; print_string "module "; ident id; print_string " :";
print_space(); modtype mty; close_box(); rem
| Tsig_modtype(id, decl) ->
modtype_declaration id decl; rem
| Tsig_class(id, decl) ->
class_type id decl;
match rem with tydecl1 :: tydecl2 :: rem -> rem | _ -> []
in signature_body true cont
and modtype_declaration id decl =
open_box 2; print_string "module type "; ident id;
begin match decl with
Tmodtype_abstract -> ()
| Tmodtype_manifest mty ->
print_string " ="; print_space(); modtype mty
end;
close_box()
(* Print a signature body (used when compiling a .mli and printing results
in interactive use). *)
let signature sg =
open_vbox 0;
signature_body false sg;
close_box()
(* Print an unification error *)
let type_expansion t t' =
if t == t' then
type_expr t
else begin
open_box 2;
type_expr t;
print_space (); print_string "="; print_space ();
type_expr t';
close_box ()
end
let rec trace fst txt =
function
(t1, t1')::(t2, t2')::rem ->
if not fst then
print_cut ();
open_box 0;
print_string "Type"; print_break 1 2;
type_expansion t1 t1'; print_space ();
txt (); print_break 1 2;
type_expansion t2 t2';
close_box ();
trace false txt rem
| _ ->
()
let unification_error tr txt1 txt2 =
reset ();
List.iter
(function (t, t') -> mark_loops t; if t != t' then mark_loops t')
tr;
open_box 0;
let (t1, t1') = List.hd tr in
let (t2, t2') = List.hd (List.tl tr) in
txt1 (); print_break 1 2;
type_expansion t1 t1'; print_space();
txt2 (); print_break 1 2;
type_expansion t2 t2';
close_box();
trace false (fun _ -> print_string "is not compatible with type")
(List.tl (List.tl tr))