React 0.13.x _classCallCheck() in DefaultRoute 'Cannot call a class as a function’

Question

I'm using React 0.13.3 with Webpack 1.9.5 and traceur-loader 0.6.3 (tried babel-loader before that), getting TypeError thrown by _classCallCheck() in DefaultRoute 'Cannot call a class as a function'. I don't see where I'm calling a class as a function. This is what my routes look like:

    var Application = require('./components/Application');
    var Home = require('./components/Home');
    var About = require('./components/About');
    var MainFeedVideos = require('./components/MainFeedVideos');
    var MyUploads = require('./components/MyUploads');
    ...
    var routes = (
            //logged out content
            <Route flux={flux} handler={Application}>
                <DefaultRoute handler={Home} />
                <Route name='about' handler={About}/>
                ...
                //logged in content
                <Route path='/' name='home' handler={Home}>
                    <DefaultRoute handler={MainFeedVideos} />
                    <Route name='my-videos' handler={MyUploads}/>
                    ...
                </Route>
            </Route>);

    Router.run(routes, Router.HistoryLocation, function (Handler) {
        React.render(<Handler/>, document.getElementById('content'));
    });

Anyone had this issue before?

Answer 1

Turns out I was using the old this.props.activeRouteHandler() instead of <RouteHandler/> in my Application and Home components, which are the top level routes. Doh.

Correct syntax examples here http://rackt.github.io/react-router/ .