Lazy Higher Order Component

LazyComponent.js

// @flow

import React, { PureComponent } from 'react';
export default function createLazyComponent<A>(
  getClass: () => Class<React.Component<void, A, void>>
) {
  return class extends PureComponent {
    componentWillMount() {
      this.lazyComponentClass = getClass();
    }

    lazyComponentClass: ?Class<React.Component<void, A, void>>;

    render() {
      const LazyComponent = this.lazyComponentClass;
      if (LazyComponent == null) {
        return null;
      }
      return (
        <LazyComponent {...this.props}>
          {this.props.children}
        </LazyComponent>
      );
    }
  };
}

usage.js

import createLazyComponent from './LazyComponent';

const LazyExpensiveComponent = createLazyComponent(() => require('./ExpensiveComponent'));