is-react

Is React

A library to determine if a variable or a statement is a React element or component. This article article describing elements and components and this article for an understanding of JSX syntax.

Install

yarn add is-react or npm i --save is-react to use the package.

Examples

// Class Component
class Foo extends React.Component {
  render(){
      return <h1>Hello</h1>;
  }
}

const foo = <Foo />;

//Functional Component
function Bar (props) { return <h1>World</h1> }
const bar = <Bar />;

// React Element
const header = <h1>Title</h1>;

// Check
isReact.compatible(Foo) // true
isReact.component(Foo); // true
isReact.classComponent(Foo); // true
isReact.functionComponent(Foo); // false
isReact.element(Foo); // false

isReact.compatible(<Foo />) // true
isReact.component(<Foo />) // false
isReact.element(<Foo />) // true
isReact.DOMTypeElement(<Foo />) // false
isReact.compositeTypeElement(<Foo />) // true

isReact.compatible(Bar) // true
isReact.component(Bar); // true
isReact.classComponent(Bar); // false
isReact.functionComponent(Bar); // true
isReact.element(Bar); // false

isReact.compatible(<Bar />) // true
isReact.component(<Bar />) // false
isReact.element(<Bar />) // true
isReact.DOMTypeElement(<Bar />) // false
isReact.compositeTypeElement(<Bar />) // true

isReact.compatible(header) // true
isReact.component(header); // false
isReact.element(header); // true
isReact.DOMTypeElement(header) // true
isReact.compositeTypeElement(header) // false

API

import isReact from 'is-react' to use the package

All functions return a boolean. The primary functions you will most likely use are compatible(), element(), and component().

isReact.compatible() Determine if a variable or statement is compatible with React. Valid React components and elements return true.

isReact.element() Determine if a variable or statement is a React element. Will return true for both DOM type and Composite type components.

isReact.component() Determine if a variable or statement is a React component. Will return true for both functional and class components.

isReact.classComponent() Determine if a variable or statement is a React class component.

isReact.functionComponent() Determine if a variable or statement is a React functional component.

isReact.DOMTypeElement() Determine if a variable or statement is a React DOM type element.

isReact.compositeTypeElement() Determine if a variable or statement is a React Composite type element.

Thanks!

Inspired by this Stackoverflow answer