What are Keyed Fragments?

The Fragments declared with the explicit <React.Fragment> syntax may have keys. The general use case is mapping a collection to an array of fragments as below,

function Glossary(props) {
return (
<dl>
{props.items.map((item) => (
// Without the `key`, React will fire a key warning
<React.Fragment key={item.id}>
<dt>{item.term}</dt>
<dd>{item.description}</dd>
</React.Fragment>
))}
</dl>
);
}

Note: key is the only attribute that can be passed to Fragment. In the future, there might be a support for additional attributes, such as event handlers.


May 29, 2022
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