text: 'use strict'
  
  import React, { Component } from 'react'
  
  const Home = () => (
      <div>
        <h2>Home</h2>
      </div>
    )
    
    const About = () => (
      <div>
        <h2>About</h2>
      </div>
    )
    
    const Topics = ({ match }) => (
      <div>
        <h2>Topics</h2>
        <ul>
          <li>
            <Link to={`${match.url}/rendering`}>Rendering with React</Link>
          </li>
          <li>
            <Link to={`${match.url}/components`}>Components</Link>
          </li>
          <li>
            <Link to={`${match.url}/props-v-state`}>Props v. State</Link>
          </li>
        </ul>
    
        <Route path={`${match.url}/:topicId`} component={Topic} />
        <Route
          exact
          path={match.url}
          render={() => <h3>Please select a topic.</h3>}
        />
      </div>
    )
    
    const Topic = ({ match }) => (
      <div>
        <h3>{match.params.topicId}</h3>
      </div>
    )
  
  export { Home, About, Topics }