exception EvalError

(* Reset the eval environment *)
let eval_reset() =
  Toploop.initialize_toplevel_env()

(* Eval some text. We get no result from this *)
let evalp txt =
  try
    let lb = (Lexing.from_string txt) in
    let phr = !Toploop.parse_toplevel_phrase lb in
    ignore(Toploop.execute_phrase false Format.std_formatter phr)
  with _ -> raise EvalError

(* Get the content of some defined variable *)
let evalv v =
  Obj.obj (Toploop.getvalue v)

(* Eval some text and then return some defined variable *)
let eval v txt =
  evalp txt;
  evalv v

(* Evaluate an expression, return the result *)
let evalexp txt =
  eval "v" ("let v = " ^ txt ^ ";;")