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Can I add a key prop to a React fragment?

I am generating a dl in React:

<dl>
  {
    highlights.map(highlight => {
      const count = text.split(highlight).length - 1;

      return (
        <>
          <dt key={`dt-${highlight.id}`}>{highlight}</dt>
          <dd key={`dd-${highlight.id}`}>{count}</dd>
        </>
      );
    })
  }
</dl>

This gives me the warning:

Warning: Each child in a list should have a unique “key” prop.

This will remove the warning, but doesn’t generate the HTML I want:

<dl>
  {
    highlights.map(highlight => {
      const count = text.split(highlight).length - 1;

      return (
        <div key={highlight.id}>
          <dt>{highlight}</dt>
          <dd>{count}</dd>
        </div>
      );
    })
  }
</dl>

And I cannot add a key prop to a fragment (<> </>).

How can work around this?


I am using React 16.12.0.

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Answer

To add a key to a fragment you need to use full Fragment syntax:

<React.Fragment key={your key}>
...
</React.Fragment>

See docs here https://reactjs.org/docs/fragments.html#keyed-fragments

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