@material-ui/core/es/utils/createChainedFunction.js

/**
 * Safe chained function
 *
 * Will only create a new function if needed,
 * otherwise will pass back existing functions or null.
 *
 * @param {function} functions to chain
 * @returns {function|null}
 */
export default function createChainedFunction(...funcs) {
  return funcs.reduce((acc, func) => {
    if (func == null) {
      return acc;
    }

    if (process.env.NODE_ENV !== 'production') {
      if (typeof func !== 'function') {
        console.error('Material-UI: Invalid Argument Type, must only provide functions, undefined, or null.');
      }
    }

    return function chainedFunction(...args) {
      acc.apply(this, args);
      func.apply(this, args);
    };
  }, () => {});
}