(** Base checker module for HTML5 conformance checking. *)

module type S = sig
  type state

  val create : unit -> state
  val reset : state -> unit

  val start_element :
    state ->
    name:string ->
    namespace:string option ->
    attrs:(string * string) list ->
    Message_collector.t ->
    unit

  val end_element :
    state -> name:string -> namespace:string option -> Message_collector.t -> unit

  val characters : state -> string -> Message_collector.t -> unit
  val end_document : state -> Message_collector.t -> unit
end

type t = (module S)

(** No-operation checker implementation. *)
module Noop = struct
  type state = unit

  let create () = ()
  let reset () = ()

  let start_element () ~name:_ ~namespace:_ ~attrs:_ _ = ()
  let end_element () ~name:_ ~namespace:_ _ = ()
  let characters () _ _ = ()
  let end_document () _ = ()
end

let noop () = (module Noop : S)