cb-state.tsx

export class TimesTableApp extends React.Component {
  changeValue = valueName => value => {
    if (isFunction(value)) {
      this.setState({ [valueName]: value(this.state[valueName]) });
    else {
      this.setState({ [valueName]: value });
    }
  };

  ...
}

export const TimesTableControls = () => {
  ...
  const play = () => {
    playTimer.current = setInterval(() => {
      setTimesTable(prevTimesTable => prevTimesTable + 0.1);
    }, 100);
  };
};