import React from "react";import {BrowserRouter as Router, Switch, Route, Link, useRouteMatch} from
                       "react-router-dom";export default function CustomLinkExample() {
  return (
    <Router>
      <div>
        <OldSchoolMenuLink
  activeOnlyWhenExact={true} to="/" label="Home" />
        <OldSchoolMenuLink to="/about" label="About" />
  <hr />
        <Switch>
          <Route exact path="/"><Home /></Route>
          <Route path="/about"><About /></Route>
        </Switch>
      </div>
    </Router>
  );}function OldSchoolMenuLink({ label, to, activeOnlyWhenExact }) {
  let match = useRouteMatch({path: to, exact: activeOnlyWhenExact });
  return (
    <div className={match ? "active" : ""}>
      {match && "> "}
      <Link to={to}>{label}</Link>
    </div>
  );}function Home() {return (<div><h2>Home</h2></div>);}function About() {return (<div><h2>About</h2></div>);}