gistfile1.go

func check(err error) {
	if err != nil {
		panic(err)
	}
}

func (h *APIHandler) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
	defer func() {
		if p := recover(); p != nil {
			switch e := p.(type) {
			case *silentError:
				// nothing

			case *clientError:
				rw.Header().Set("Content-Type", "text/plain; charset=utf-8")
				rw.WriteHeader(400)
				fmt.Fprintln(rw, e.err.Error())

			default:
				rw.Header().Set("Content-Type", "text/plain; charset=utf-8")
				rw.WriteHeader(500)
				fmt.Fprintln(rw, "internal error")
			}
		}
	}
	
	...
}

func (h *APIHandler) Updates(rw http.ResponseWriter, req *http.Request) {
...
  check(err)
...
}