import * as React from "react" ; import { shallowEqual } from "./shallowEqual" ; export class PureComponent < T , S = { } , SS = any > extends React . Component < T , S , SS > { public shouldComponentUpdate ( nextProps , nextState , nextContext ) { return ( ! shallowEqual ( this . props , nextProps ) || ! shallowEqual ( this . state , nextState ) || ! shallowEqual ( this . context , nextContext ) ) ; } }