- var_dump: documentation ( source)
- sprintf: documentation ( source)
<?php
$required = !empty($field["required"]) ? "form-required" : "";
$buffer = sprintf("
<tr class='form-field %s'>
<th scope='row'>%s</th>
<td>
%s
<p>%s</p>
</td>
</tr>
", $required, "meta", "<input type='text' name='hello'", "");
var_dump($buffer);