dune

(* -*- tuareg -*- *)

open StdLabels
open Jbuild_plugin.V1

let version = Scanf.sscanf ocaml_version "%u.%u" (fun a b -> (a, b))

let modules_in_4_02 =
  [ "Arg"
  ; "Array"
  ; "ArrayLabels"
  ; "Buffer"
  ; "Bytes"
  ; "BytesLabels"
  ; "Callback"
  ; "Char"
  ; "Complex"
  ; "Digest"
  ; "Filename"
  ; "Format"
  ; "Gc"
  ; "Genlex"
  ; "Hashtbl"
  ; "Int32"
  ; "Int64"
  ; "Lazy"
  ; "Lexing"
  ; "List"
  ; "ListLabels"
  ; "Map"
  ; "Marshal"
  ; "MoreLabels"
  ; "Nativeint"
  ; "Obj"
  ; "Oo"
  ; "Parsing"
  ; "Pervasives"
  ; "Printexc"
  ; "Printf"
  ; "Queue"
  ; "Random"
  ; "Scanf"
  ; "Set"
  ; "Stack"
  ; "StdLabels"
  ; "Stream"
  ; "String"
  ; "StringLabels"
  ; "Sys"
  ; "Weak"
  ]

let missing_modules =
  if version < (4, 07) then
    ["Stdlib"]
  else if version < (4, 11) then
    (* For OCaml 4.07-4.10 incl. this solves the problem of being unable to
       generate empty .cmxa files on MSVC by duplicating the Pervasives module
       (and updating its deprecation warning not to refer to this library! *)
    ["Pervasives"]
  else
    []

let available_modules =
  if version > (4, 02) then
    "Uchar" :: modules_in_4_02
  else
    modules_in_4_02

let longest_module_name =
  List.fold_left available_modules ~init:0
    ~f:(fun acc m -> max acc (String.length m))

let () =
  Printf.ksprintf send {|
(library
 (wrapped false)
 (name stdlib_shims)
 (modules %s)
 (public_name stdlib-shims))

(rule
 (with-stdout-to stdlib.ml
  (echo "\
%s

include Pervasives
")))
|}
    (String.concat ~sep:" " missing_modules)
    (List.map available_modules
       ~f:(fun m -> Printf.sprintf "module %-*s = %s" longest_module_name m m)
     |> String.concat ~sep:"\n")