# `react-is` This package allows you to test arbitrary values and see if they're a particular React element type. ## Installation ```sh # Yarn yarn add react-is # NPM npm install react-is ``` ## Usage ### Determining if a Component is Valid ```js import React from "react"; import * as ReactIs from "react-is"; class ClassComponent extends React.Component { render() { return React.createElement("div"); } } const FunctionComponent = () => React.createElement("div"); const ForwardRefComponent = React.forwardRef((props, ref) => React.createElement(Component, { forwardedRef: ref, ...props }) ); const Context = React.createContext(false); ReactIs.isValidElementType("div"); // true ReactIs.isValidElementType(ClassComponent); // true ReactIs.isValidElementType(FunctionComponent); // true ReactIs.isValidElementType(ForwardRefComponent); // true ReactIs.isValidElementType(Context.Provider); // true ReactIs.isValidElementType(Context.Consumer); // true ``` ### Determining an Element's Type #### Context ```js import React from "react"; import * as ReactIs from 'react-is'; const ThemeContext = React.createContext("blue"); ReactIs.isContextConsumer(); // true ReactIs.isContextProvider(); // true ReactIs.typeOf() === ReactIs.ContextProvider; // true ReactIs.typeOf() === ReactIs.ContextConsumer; // true ``` #### Element ```js import React from "react"; import * as ReactIs from 'react-is'; ReactIs.isElement(

); // true ReactIs.typeOf(

) === ReactIs.Element; // true ``` #### Fragment ```js import React from "react"; import * as ReactIs from 'react-is'; ReactIs.isFragment(<>); // true ReactIs.typeOf(<>) === ReactIs.Fragment; // true ``` #### Portal ```js import React from "react"; import ReactDOM from "react-dom"; import * as ReactIs from 'react-is'; const div = document.createElement("div"); const portal = ReactDOM.createPortal(

, div); ReactIs.isPortal(portal); // true ReactIs.typeOf(portal) === ReactIs.Portal; // true ``` #### StrictMode ```js import React from "react"; import * as ReactIs from 'react-is'; ReactIs.isStrictMode(); // true ReactIs.typeOf() === ReactIs.StrictMode; // true ```

c	File Name	Size	T	Date
zip	cjs/	4096	---	2026-04-24 21:03:10
-	LICENSE	1088	%	2026-04-10 03:13:10
-	README.md	2314	md	2026-04-10 03:13:18
-	index.js	192	js	2026-04-10 03:13:16
-	package.json	540	json	2026-04-10 03:13:17

🌲 / work projects ballbox node_modules next dist compiled react-is

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