        <Switch>
          <Route exact path='/signin' component={AuthView} />
          <Route exact path='/dashboard' component={Dashboard} />
          <Route exact path='/' component={HomePage} />
          <Route path='/course/:courseID' render={({match}: RouteComponentProps) => {
            return (
              <CourseView id={(match.params as {courseID: string}).courseID}/>
            );
          }}/>
          <Route path='/enroll/:courseID' render={({match}: RouteComponentProps) => {
            return (
              <JoinCourseView id={(match.params as { courseID: string }).courseID}/>
            );  