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A common pattern in React is for a component to return multiple elements. Fragments let you group a list of children without adding extra nodes to the DOM.

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render() {\n  return (\n    <React.Fragment>\n      <ChildA />\n      <ChildB />\n      <ChildC />\n    </React.Fragment>\n  );\n}
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There is also a new short syntax for declaring them.

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Motivation

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A common pattern is for a component to return a list of children. Take this example React snippet:

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class Table extends React.Component {\n  render() {\n    return (\n      <table>\n        <tr>\n          <Columns />\n        </tr>\n      </table>\n    );\n  }\n}
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<Columns /> would need to return multiple <td> elements in order for the rendered HTML to be valid. If a parent div was used inside the render() of <Columns />, then the resulting HTML will be invalid.

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class Columns extends React.Component {\n  render() {\n    return (\n      <div>\n        <td>Hello</td>\n        <td>World</td>\n      </div>\n    );\n  }\n}
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results in a <Table /> output of:

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<table>\n  <tr>\n    <div>\n      <td>Hello</td>\n      <td>World</td>\n    </div>\n  </tr>\n</table>
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Fragments solve this problem.

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Usage

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class Columns extends React.Component {\n  render() {\n    return (\n      <React.Fragment>        <td>Hello</td>\n        <td>World</td>\n      </React.Fragment>    );\n  }\n}
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which results in a correct <Table /> output of:

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<table>\n  <tr>\n    <td>Hello</td>\n    <td>World</td>\n  </tr>\n</table>
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Short Syntax

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There is a new, shorter syntax you can use for declaring fragments. It looks like empty tags:

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class Columns extends React.Component {\n  render() {\n    return (\n      <>        <td>Hello</td>\n        <td>World</td>\n      </>    );\n  }\n}
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You can use <></> the same way you’d use any other element except that it doesn’t support keys or attributes.

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Keyed Fragments

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Fragments declared with the explicit <React.Fragment> syntax may have keys. A use case for this is mapping a collection to an array of fragments — for example, to create a description list:

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function Glossary(props) {\n  return (\n    <dl>\n      {props.items.map(item => (\n        // Without the `key`, React will fire a key warning\n        <React.Fragment key={item.id}>\n          <dt>{item.term}</dt>\n          <dd>{item.description}</dd>\n        </React.Fragment>\n      ))}\n    </dl>\n  );\n}
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key is the only attribute that can be passed to Fragment. In the future, we may add support for additional attributes, such as event handlers.

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Live Demo

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You can try out the new JSX fragment syntax with this CodePen.

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