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open Cmdliner
let sub_term = Term.const ()
let main_term =
let what = Arg.(value & pos 0 (some string) None & info [] ~docv:"WHAT") in
let doc what = `Help (`Pager, what) in
Term.(ret (const doc $ what))
let sub_info info = info "sub" ~doc:"description of sub"
let main_info info = info "main" ~doc:"description of main"
module Old = struct
[@@@alert "-deprecated"]
let term_info n ~doc = Term.info n ~doc
let sub_cmd = sub_term, sub_info term_info
let main_cmd = main_term, main_info term_info
let main ~argv = Term.exit (Term.eval_choice ~argv main_cmd [sub_cmd])
end
module New = struct
let cmd_info n ~doc = Cmd.info n ~doc
let sub_cmd = Cmd.v (sub_info cmd_info) sub_term
let main_cmd = main_term, main_info cmd_info
let main = Cmd.group ~default:main_term (main_info cmd_info) [sub_cmd]
let main ~argv = exit (Cmd.eval ~argv main)
end
let main () =
let argv, backend = match Array.to_list Sys.argv with
| exec :: backend :: rest -> Array.of_list (exec :: rest), backend
| [_] -> prerr_endline "Need to specify a backend: old or new"; exit 1
| _ -> assert false
in
match backend with
| "old" -> Old.main ~argv
| "new" -> New.main ~argv
| b -> prerr_endline ("Unknown backend: " ^ b)
let () = main ()
|
