Function make_handler

pub fn make_handler<F, RespBody, Err, Ret>(f: F) -> HandlerFn<F>
where
    RespBody: Body,
    Err: Into<Box<dyn Error + Send + Sync>>,
    Ret: Future<Output = Result<Response<RespBody>, Err>>,
    F: Fn(Request<ReqBody>) -> Ret,