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|
type t =
{ x : int
; y : u
}
and u = A of int | B of t
[@@deriving traverse]
[%%expect{|
type t = { x : int; y : u; }
and u = A of int | B of t
class virtual map :
object
method virtual int : int -> int
method t : t -> t
method u : u -> u
end
class virtual iter :
object
method virtual int : int -> unit
method t : t -> unit
method u : u -> unit
end
class virtual ['acc] fold :
object
method virtual int : int -> 'acc -> 'acc
method t : t -> 'acc -> 'acc
method u : u -> 'acc -> 'acc
end
class virtual ['acc] fold_map :
object
method virtual int : int -> 'acc -> int * 'acc
method t : t -> 'acc -> t * 'acc
method u : u -> 'acc -> u * 'acc
end
class virtual ['ctx] map_with_context :
object
method virtual int : 'ctx -> int -> int
method t : 'ctx -> t -> t
method u : 'ctx -> u -> u
end
class virtual ['res] lift :
object
method virtual constr : string -> 'res list -> 'res
method virtual int : int -> 'res
method virtual record : (string * 'res) list -> 'res
method t : t -> 'res
method u : u -> 'res
end
class virtual ['ctx, 'res] lift_map_with_context :
object
method virtual constr : 'ctx -> string -> 'res list -> 'res
method virtual int : 'ctx -> int -> int * 'res
method virtual record : 'ctx -> (string * 'res) list -> 'res
method t : 'ctx -> t -> t * 'res
method u : 'ctx -> u -> u * 'res
end
|}]
type t =
{ a : int
; b : Int.t
; c : (int, bool) Stdlib.Result.t
; d : int Map.Make(Int).t
}
[@@deriving traverse_iter]
[%%expect{|
type t = {
a : int;
b : int;
c : (int, bool) result;
d : int Map.Make(Int).t;
}
class virtual iter :
object
method virtual bool : bool -> unit
method virtual int : int -> unit
method virtual int__t : int -> unit
method virtual map__make_'int'__t :
('a -> unit) -> 'a Map.Make(Int).t -> unit
method virtual stdlib__result__t :
('a -> unit) -> ('b -> unit) -> ('a, 'b) result -> unit
method t : t -> unit
end
|}]
type t = Inline of { a : string option; b : t }
[@@deriving traverse]
[%%expect{|
type t = Inline of { a : string option; b : t; }
class virtual map :
object
method virtual option : ('a -> 'a) -> 'a option -> 'a option
method virtual string : string -> string
method t : t -> t
end
class virtual iter :
object
method virtual option : ('a -> unit) -> 'a option -> unit
method virtual string : string -> unit
method t : t -> unit
end
class virtual ['acc] fold :
object
method virtual option : ('a -> 'acc -> 'acc) -> 'a option -> 'acc -> 'acc
method virtual string : string -> 'acc -> 'acc
method t : t -> 'acc -> 'acc
end
class virtual ['acc] fold_map :
object
method virtual option :
('a -> 'acc -> 'a * 'acc) -> 'a option -> 'acc -> 'a option * 'acc
method virtual string : string -> 'acc -> string * 'acc
method t : t -> 'acc -> t * 'acc
end
class virtual ['ctx] map_with_context :
object
method virtual option :
('ctx -> 'a -> 'a) -> 'ctx -> 'a option -> 'a option
method virtual string : 'ctx -> string -> string
method t : 'ctx -> t -> t
end
class virtual ['res] lift :
object
method virtual constr : string -> 'res list -> 'res
method virtual option : ('a -> 'res) -> 'a option -> 'res
method virtual record : (string * 'res) list -> 'res
method virtual string : string -> 'res
method t : t -> 'res
end
class virtual ['ctx, 'res] lift_map_with_context :
object
method virtual constr : 'ctx -> string -> 'res list -> 'res
method virtual option :
('ctx -> 'a -> 'a * 'res) -> 'ctx -> 'a option -> 'a option * 'res
method virtual record : 'ctx -> (string * 'res) list -> 'res
method virtual string : 'ctx -> string -> string * 'res
method t : 'ctx -> t -> t * 'res
end
|}]
(* Test [Ast_traverse.sexp_of] and compare it visually to [Pprintast]. *)
let via_pprintast, via_sexp_of =
let open Stdppx in
(* Pretty-print a string by turning it into a multi-line list, all padded to the same
length. This forces the value printer to split every string onto its own line.
Otherwise it may put multiple indented strings onto one line, which is unreadable. *)
let pretty string =
let lines = String.split_on_char string ~sep:'\n' in
let len =
List.fold_left lines ~init:0 ~f:(fun acc string ->
Int.max acc (String.length string))
in
List.map lines ~f:(fun string ->
string ^ String.make (len - String.length string) ' ')
in
(* Tests dotted identifier, infix operator, attributes, and [Location.none]. *)
let expr =
let loc = Ppxlib.Location.none in
[%expr
function
| 0 -> true
| 1 -> false
| n -> (f [@tailcall]) (Stdlib.Int.( - ) n 2)]
in
(* Tests locations and [loc_ghost]. *)
let structure =
let loc : Ppxlib.Location.t =
{
loc_ghost = true;
loc_start = { pos_fname = "file.ml"; pos_lnum = 2; pos_bol = 1; pos_cnum = 2 };
loc_end = { pos_fname = "file.ml"; pos_lnum = 4; pos_bol = 6; pos_cnum = 9 };
}
in
[%str
module M = struct
let rec f = [%e expr]
end]
in
(* Render two different ways. *)
let via_pprintast = Ppxlib.Pprintast.string_of_structure structure |> pretty in
let via_sexp_of =
structure
|> Ppxlib.Ast_traverse.sexp_of#structure
|> Sexp.to_string_hum
|> pretty
in
via_pprintast, via_sexp_of
[%%expect{|
val via_pprintast : string list =
["module M = ";
" struct ";
" let rec f = ";
" function ";
" | 0 -> true ";
" | 1 -> false ";
" | n -> ((f)[@tailcall ]) (Stdlib.Int.(-) n 2)";
" end "]
val via_sexp_of : string list =
["(((pstr_desc ";
" (Pstr_module ";
" ((pmb_name ";
" ((txt (M)) (loc \"File \\\"file.ml\\\", line 2, characters 1-8:<ghost>\"))) ";
" (pmb_expr ";
" ((pmod_desc ";
" (Pmod_structure ";
" (((pstr_desc ";
" (Pstr_value Recursive ";
" (((pvb_pat ";
" ((ppat_desc ";
" (Ppat_var ";
" ((txt f) ";
" (loc \"File \\\"file.ml\\\", line 2, characters 1-8:<ghost>\"))))";
" (ppat_loc ";
" \"File \\\"file.ml\\\", line 2, characters 1-8:<ghost>\"))) ";
" (pvb_expr ";
" (Pexp_function () () ";
" (Pfunction_cases ";
" (((pc_lhs (Ppat_constant (Pconst_integer 0 ()))) ";
" (pc_rhs (Pexp_construct true ()))) ";
" ((pc_lhs (Ppat_constant (Pconst_integer 1 ()))) ";
" (pc_rhs (Pexp_construct false ()))) ";
" ((pc_lhs (Ppat_var n)) ";
" (pc_rhs ";
" (Pexp_apply ";
" ((pexp_desc (Pexp_ident f)) (pexp_loc_stack (())) ";
" (pexp_attributes ";
" (((attr_name tailcall) (attr_payload (PStr ())))))) ";
" ((Nolabel ";
" ((pexp_desc ";
" (Pexp_apply (Pexp_ident \"Stdlib.Int.( - )\") ";
" ((Nolabel (Pexp_ident n)) ";
" (Nolabel (Pexp_constant (Pconst_integer 2 ())))))) ";
" (pexp_loc_stack (()))))))))) ";
" () ()))) ";
" (pvb_loc \"File \\\"file.ml\\\", line 2, characters 1-8:<ghost>\")))))";
" (pstr_loc \"File \\\"file.ml\\\", line 2, characters 1-8:<ghost>\"))))) ";
" (pmod_loc \"File \\\"file.ml\\\", line 2, characters 1-8:<ghost>\"))) ";
" (pmb_loc \"File \\\"file.ml\\\", line 2, characters 1-8:<ghost>\")))) ";
" (pstr_loc \"File \\\"file.ml\\\", line 2, characters 1-8:<ghost>\"))) "]
|}]
|
