import React, { Component } from 'react'; class E extends Component { constructor(props) { super(props); this.state = { e: 0, }; this.timer = this.timer.bind(this); } componentDidMount() { const eId = setInterval(this.timer, 10); this.setState({ eInterval: eId }); } componentWillUnmount() { clearInterval(this.state.eInterval); } timer() { this.setState({ e: this.state.e + 1 }); } render() { const e = Array(this.state.e).fill(

e

); return e; } } export default E;