'feeds_tamper_sprintf_form', 'callback' => 'feeds_tamper_sprintf_callback', 'name' => 'Format string', 'multi' => 'loop', 'category' => 'Text', ); function feeds_tamper_sprintf_form($importer, $element_key, $settings) { $form = array(); $form['format'] = array( '#type' => 'textfield', '#title' => t('Format'), '#default_value' => '%s', '#size' => 60, '#maxlength' => 128, '#required' => FALSE, '#description' => t('See the sprintf documentation for more details.'), ); return $form; } function feeds_tamper_sprintf_callback($result, $item_key, $element_key, &$field, $settings, $source) { $field = sprintf($settings['format'], $field); }