React-redux语法错误：预期的意外令牌，

Question

我试图在我的主反应（index.js）中添加下面提到的javascript代码 但是在（函数hookHistoryBoomerang（））的位置出现意外的令牌错误。

import React from 'react'
import {
    render
} from 'react-dom'
import {
    createStore
} from 'redux'
import {
    Provider
} from 'react-redux'
import App from './components/App'
import reducer from './reducers'

(function () {
    var history;
    var hadRouteChange = false;
    var hookOptions = {};
    if (BOOMR.plugins.History || typeof BOOMR.plugins.SPA === "undefined") {
        return;
    }
    BOOMR.plugins.SPA.register("History");
    BOOMR.plugins.History = {
        function hookHistoryBoomerang() {
            if (window.BOOMR && BOOMR.version) {
                if (BOOMR.plugins && BOOMR.plugins.History) {
                    BOOMR.plugins.History.hook(history, hadRouteChange);
                }
                return true;
            }
        }
        if (!hookHistoryBoomerang()) {
            if (document.addEventListener) {
                document.addEventListener("onBoomerangLoaded", hookHistoryBoomerang);
            } else if (document.attachEvent) {
                document.attachEvent("onpropertychange", function (e) {
                    e = e || window.event;
                    if (e && e.propertyName === "onBoomerangLoaded") {
                        hookHistoryBoomerang();
                    }
                });
            }
        }

        function onEnter() {
            hadRouteChange = true;
        }
    };
}(BOOMR.window));

const store = createStore(reducer)

render(
  <Provider store={ store }>
    <Router history={ history } onEnter={ onEnter } />
    <App />
  </Provider>,
  document.getElementById('root')
)

1.我的代码出了什么问题？

2.如果我错过任何事情，请帮我解决这个问题。