printer.ml

open Core_kernel.Std

module type Itemize = sig
  val dump : string list -> string
end

module HTML : Itemize = struct
  let dump xs =
    let buf = Buffer.create 0 in
    let put_item x =
      Buffer.add_string buf "<li>";
      Buffer.add_string buf x;
      Buffer.add_string buf "<li>";
    in
    Buffer.add_string buf "<ul>";
    List.iter xs ~f:put_item;
    Buffer.add_string buf "</ul>";
    Buffer.contents buf
end

module Text : Itemize = struct
  let dump xs =
    let buf = Buffer.create 0 in
    let put_item x =
      Buffer.add_string buf "- ";
      Buffer.add_string buf x;
      Buffer.add_string buf "\n";
    in
    List.iter xs ~f:put_item;
    Buffer.contents buf
end


let printer title content ((module M): (module Itemize)) =
  Printf.printf "** %s **\n" (title);
  print_string @@ M.dump content


let main title flag =
  let xs = ["foo"; "bar"; "boo";] in
  match flag with
  | "html" | "HTML" -> printer title xs (module HTML)
  | _ -> printer title xs (module Text)


let () =
  main Sys.argv.(1) Sys.argv.(2)