root/tags/1.5.1/wp-admin/edit-tag-form.php

<?php
if ( ! empty($tag_ID) ) {
    $heading = __('Edit Tag');
    $submit_text = __('Edit Tag');
    $form = '<form name="edittag" id="edittag" method="post" action="edit-tags.php" class="validate">';
    $action = 'editedtag';
    $nonce_action = 'update-tag_' . $tag_ID;
    do_action('edit_tag_form_pre', $tag);
} else {
    $heading = __('Add Tag');
    $submit_text = __('Add Tag');
    $form = '<form name="addtag" id="addtag" method="post" action="edit-tags.php" class="add:the-list: validate">';
    $action = 'addtag';
    $nonce_action = 'add-tag';
    do_action('add_tag_form_pre', $tag);
}
?>

<div class="wrap">
<h2><?php echo $heading ?></h2>
<div id="ajax-response"></div>
<?php echo $form ?>
<input type="hidden" name="action" value="<?php echo $action ?>" />
<input type="hidden" name="tag_ID" value="<?php echo $tag->term_id ?>" />
<?php wp_original_referer_field(true, 'previous'); wp_nonce_field($nonce_action); ?>
    <table class="form-table">
        <tr class="form-field form-required">
            <th scope="row" valign="top"><label for="name"><?php _e('Tag name') ?></label></th>
            <td><input name="name" id="name" type="text" value="<?php echo attribute_escape($tag->name); ?>" size="40" />
            <p><?php _e('The name is how the tag appears on your site.'); ?></p></td>
        </tr>
        <tr class="form-field">
            <th scope="row" valign="top"><label for="slug"><?php _e('Tag slug') ?></label></th>
            <td><input name="slug" id="slug" type="text" value="<?php echo attribute_escape($tag->slug); ?>" size="40" />
            <p><?php _e('The &#8220;slug&#8221; is the URL-friendly version of the name. It is usually all lowercase and contains only letters, numbers, and hyphens.'); ?></p></td>
        </tr>
    </table>
<p class="submit"><input type="submit" class="button" name="submit" value="<?php echo $submit_text ?>" /></p>
<?php do_action('edit_tag_form', $tag); ?>
</form>
</div>