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TypeScript Error: Unexpected token `div`. Expected jsx identifier

TypeScript Error: Unexpected token `div`. Expected jsx identifier

Matthew C.

—

The ProblemJump To Solution

You are building a Next.js app and encounter the following error:

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Error: Unexpected token `div`. Expected jsx identifier

As an example, adding the following code to the /src/app/page.tsx file will cause the error:

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export default function Home() {
  const casesArr = [{ id: 1, name: "Case 1" }, { id: 2, name: "Case 2" }, { id: 3, name: "Case 3" }];

  return (
    <div>
      <ul>
        {casesArr.map((case) => (
          <li key={case.id}>{case.name}</li>
        ))}
      </ul>
    </div>
  );
}

The Unexpected token error is a JavaScript syntax error. It occurs when a specific language construct is expected but not provided. In this case, TypeScript was expecting JSX to be returned but came across something unexpected.

The Solution

The issue may be due to a typo. It can also be due to using reserved JavaScript words, missing property values, extra or missing parentheses, or due to a trailing comma being in a place where an expression is expected.

Don’t Use Reserved JavaScript Words

To fix the code example above, change the name of the callback function argument in the map array method:

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export default function Home() {
  const casesArr = [{ id: 1, name: "Case 1" }, { id: 2, name: "Case 2" }, { id: 3, name: "Case 3" }];

  return (
    <div>
      <ul>
        {casesArr.map((caseItem) => (
          <li key={caseItem.id}>{caseItem.name}</li>
        ))}
      </ul>
    </div>
  );
}

The word case is a reserved word in JavaScript. You can’t use reserved words as identifiers for variables, functions, classes, etc.

Missing Property Palue

The error can also be caused by a missing property value:

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    <Image src="/next.svg" alt="logo" width={} height={200} />

Extra Parentheses or Missing Parentheses

An extra parenthesis can cause the issue:

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    <Image src="/next.svg" alt="logo" width={20} height={200}} />

Missing parentheses can also cause an error:

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    <Image src="/next.svg" alt="logo" width={20} height={200 />

Expression Expected

If you add a trailing comma where an expression is expected, such as after a map() function, you’ll get the error:

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    <ul>
      {casesArr.map((caseItem) => (
        <li key={caseItem.id}>{caseItem.name}</li>
      )),}
    </ul>

You can fix the error by removing the comma, or by adding an expression like:

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    <ul>
      {casesArr.map((caseItem) => (
        <li key={caseItem.id}>{caseItem.name}</li>
      )).reverse()}
    </ul>
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