expression expected and Syntax error: Unexpected token jsx nextjs

Question

To render a table from array I used

const Posts: NextPage = ({ posts}: any) => {
  return (
    <>
       .....
       <tbody>
         {
           posts.map((post: any) => {
           const _date = new Date(post.expiryDate);
           const _expiryDate = `${_date.getFullYear()}-${_date.getMonth()}-${_date.getDay()}`;
           return <tr key={post._id} onClick={() => showDetails(post)}>
             <td>{post.type}</td>
             <td>{_expiryDate}</td>
           </tr>;
        })
       }
       </tbody>

And this works perfectly. On click of any row I pass the post data to new component to show the details.

So on the detail page I am using

<tr>

  <td className="table-key">Expiry</td>
  <td className="table-value">{post.expiryDate}</td>
  {
    const _date = new Date(post.expiryDate);
    const _expiryDate = `${_date.getFullYear()}-${_date.getMonth()}-${_date.getDay()}`;
    return <td className="table-value">{_expiryDate}</td>;
  }
</tr>

but this is showing Expression expected and on the console

Syntax error: Unexpected token

On the list page same kind of expression is working? What is the issue?

Answer 1

In your error case, you are using {} in JSX which is Embedding Expressions in JSX

Using a {} inside jsx is similar to return({}) , just like in normal js, you can't declare a new variable there, but with another map, filter you can.

This will throw an error because this expression is invalid inside that {} .

You would need to render your code block inside another function:

const renderExpiryDate = () => {
    const _date = new Date(post.expiryDate);
    const _expiryDate = `${_date.getFullYear()}-${_date.getMonth()}-${_date.getDay()}`;
    return <td className="table-value">{_expiryDate}</td>;
}

Then bring it down to JSX:

<tr>
  <td className="table-key">Expiry</td>
  <td className="table-value">{post.expiryDate}</td>
  {renderExpiryDate()}
</tr>

---

In the first case, you won't get a similar error because your expression is inside a map function which is normal javascripts.