reason - ReasonReact コンパイル時エラーの「self.send」

Question

以下を考えると：

$cat src/Greeting.re
let component = ReasonReact.reducerComponent("Greeting");

type action =
 | Click;

type state = {
    count: int
};

let make = (_children) => {
  ...component,
  initialState: () => {count: 0},
  reducer: (action, state) =>
    ReasonReact.Update({count: state.count + 1}),
  render: (self) => {
     let message = "Clicked " ++ string_of_int(self.state.count) ++ "x";
        <div>
          <button
            onClick={_event => self.send(Click)}
          />
          {ReasonReact.stringToElement(message)}
        </div>
  }
};

次のコンパイル時エラーが発生します。

  17 ┆ <div>
  18 ┆   <button
  19 ┆     onClick={_event => self.send(Click)}
  20 ┆   />
  21 ┆   {ReasonReact.stringToElement(message)}

  This record expression is expected to have type
    ReasonReact.componentSpec (state,  'a,  'b,  'c,  'd)
  The field send does not belong to type ReasonReact.self

ninja: build stopped: subcommand failed.
>>>> Finish compiling(exit: 1)

理解できない。誰かがエラーの内容と修正方法を説明してもらえますか?