Expected an assignment or function call and instead saw an expression error

Question

Having a slight issue with some code that I have written, I keep getting the error:

expected an assignment or function call and instead saw an expression

I have commented where the error is happening. Not sure what the issue is however. Code is as follows:

renderBody() {
    const { bookings } = this.props;
    if (bookings.length > 0) {
        return (
            Object.keys(bookings).map(e => (
                <TableBody>
                    {Object.values(bookings[e]).forEach((value) => {
                        <TableCell>{value}</TableCell>; //<-ERROR??
                    })}
                </TableBody>
            ))
        );
    }
    return null;
}

Answer 1

Because you are not doing anything inside forEach (no assignment, no calculation), also forEach will not return anything, use map to return the TableCell for each array entry.

Eslint will throw an error, if you write a forEach loop without any operation.

Write it like this:

{Object.values(bookings[e]).map(value => (
    <TableCell>{value}</TableCell>
))}