anchor.diff:      | JSON_Boolean of bool
       | JSON_List of JSON list
       | JSON_Obj of (string * JSON) list
  -   ******))))
  +   ******)))))
        
   let rec stringify (json : JSON) : string =
       let s_name (s : string) : string = "\"" + s + "\""
  
positive.code: 
          let rec parse_obj (acc : (string * JSON) list) (tokens : Token list) : (JSON * Token list) = 
              match tokens with
              | String name :: Colon :: Null :: ts ->
                  parse_obj ((string name, JSON_Null) :: acc) ts
              | String name :: Colon :: String s :: ts ->
                  parse_obj ((string name, JSON_String s) :: acc) ts
  
negative.code:     let rec parse' (tokens : Token list) : (JSON * Token list) =
          let rec parse_list (acc : JSON list) (tokens : Token list) : (JSON * Token list) =
              match tokens with
              | Null :: ts -> /// переписать под parse_obj
                  parse_list ((JSON_Null) :: acc) ts
              | String s :: ts ->
                  parse_list ((JSON_String s) :: acc) ts
  