configure

#!/usr/bin/env ocaml -I +unix unix.cma

(* ./configure generates a file config.ml. *)

let version = "Zrun.2025"
let subversion = "dev"

let prefix = "_build/install/default/"
let suffix = "share/zrun"

(* let prefix = "_build/default/lib/std/" and suffix = "" *)

let prefix = ref (Filename.concat (Sys.getcwd ()) prefix)

let get_stdlib_prefix () = Filename.concat !prefix suffix

let get_current_date () =
  let open Unix in
  let t = gmtime @@ time () in
  Printf.sprintf
    "%.2d-%.2d-%d-%d:%d"
    (1900 + t.tm_year) (1 + t.tm_mon) t.tm_mday 
    t.tm_hour t.tm_min

let () =
  let options =
    [
      "--prefix", Arg.Set_string prefix, " Installation prefix";
    ]
  in
  Arg.parse
    options
    (fun cmd ->
      Printf.eprintf "Don't know what to do with \"%s\".\n" cmd;
      exit 1)
    "Usage: ./configure [OPTIONS]";

  (* Generate configuration module. *)
  let statements =
    let dquote s = "\"" ^ s ^ "\"" in
    [
      "version", dquote @@ version;
      "subversion", dquote @@ subversion;
      "stdlib", dquote @@ get_stdlib_prefix ();
      "date", dquote @@ get_current_date ();
    ]
  in
  let oc = open_out_bin "config.ml" in
  List.iter
    (fun (x, s) -> Printf.fprintf oc {|let %s = %s
|} x s)
    statements;
  close_out oc;