import PropTypes from 'prop-types';MyComponent.propTypes = {  // You can declare that a prop is a specific JS type. By default, these  // are all optional.
  optionalArray: PropTypes.array,
  optionalBool: PropTypes.bool,
  optionalFunc: PropTypes.func,
  optionalNumber: PropTypes.number,
  optionalObject: PropTypes.object,
  optionalString: PropTypes.string,
  optionalSymbol: PropTypes.symbol,  // Anything that can be rendered: numbers, strings, elements or an array  // (or fragment) containing these types.
  optionalNode: PropTypes.node,  // A React element.
  optionalElement: PropTypes.element,  // A React element type (ie. MyComponent).
  optionalElementType: PropTypes.elementType,  // You can also declare that a prop is an instance of a class. This uses  // JS's instanceof operator.
  optionalMessage: PropTypes.instanceOf(Message),  // You can ensure that your prop is limited to specific values by treating  // it as an enum.
  optionalEnum: PropTypes.oneOf(['News', 'Photos']),  // An object that could be one of many types
  optionalUnion: PropTypes.oneOfType([
    PropTypes.string,
    PropTypes.number,
    PropTypes.instanceOf(Message)
  ]),  // An array of a certain type
  optionalArrayOf: PropTypes.arrayOf(PropTypes.number),  // An object with property values of a certain type
  optionalObjectOf: PropTypes.objectOf(PropTypes.number),  // An object taking on a particular shape
  optionalObjectWithShape: PropTypes.shape({
    color: PropTypes.string,
    fontSize: PropTypes.number
  }),  // An object with warnings on extra properties
  optionalObjectWithStrictShape: PropTypes.exact({
    name: PropTypes.string,
    quantity: PropTypes.number
  }),     // You can chain any of the above with `isRequired` to make sure a warning  // is shown if the prop isn't provided.
  requiredFunc: PropTypes.func.isRequired,  // A required value of any data type
  requiredAny: PropTypes.any.isRequired,  // You can also specify a custom validator. It should return an Error  // object if the validation fails. Don't `console.warn` or throw, as this  // won't work inside `oneOfType`.
  customProp: function(props, propName, componentName) {
    if (!/matchme/.test(props[propName])) {
      return new Error(
        'Invalid prop `' + propName + '` supplied to' +
        ' `' + componentName + '`. Validation failed.'
      );}
  },  // You can also supply a custom validator to `arrayOf` and `objectOf`.  // It should return an Error object if the validation fails. The validator  // will be called for each key in the array or object. The first two  // arguments of the validator are the array or object itself, and the  // current item's key.
  customArrayProp: PropTypes.arrayOf(function(propValue, key, componentName, location, propFullName) {
    if (!/matchme/.test(propValue[key])) {
      return new Error(
        'Invalid prop `' + propFullName + '` supplied to' +
        ' `' + componentName + '`. Validation failed.'
      );}
  })};