Why is componentDidMount() not looping?

Question

React

import React, {Component} from 'react';


class Clock extends Component {
  constructor(props) {
    super(props);
    this.state = {
      vall: 0};
  }

  componentDidMount() {
    this.setState({val: 5})
    
  }

  render() {
    return (
      <div>
        <h1>Привет, мир!</h1>
      </div>
    );
  }
}

export default Clock;

After all, componentDidMount () is executed after rendering and changes the state, after which everything should repeat in a circle.

Answer 1

The rerender happens only 2 times.

You may call setState() immediately in componentDidMount(). It will trigger an extra rendering, but it will happen before the browser updates the screen. This guarantees that even though the render() will be called twice in this case , the user won't see the intermediate state.

Read the documentation carefully.