Why can only class components be used as error boundaries in React?

Error boundaries need two special lifecycle methods, getDerivedStateFromError and componentDidCatch, which are only available on class components. There is currently no hook version of these methods, so even in a codebase built entirely with function components, error boundaries still need to be written as a small class component.

class ErrorBoundary extends React.Component {
  state = { hasError: false };
  static getDerivedStateFromError() {
    return { hasError: true };
  }
  render() {
    if (this.state.hasError) return <h1>Something went wrong</h1>;
    return this.props.children;
  }
}