categories hierarchical FIX

function wsp_return_content_type_categories( $is_title_displayed=true, $display_nofollow=false, $sort=null,$cat=0,$return=false ) {

	// init
	$return = '';

	// args
	$args = array();

	$args['parent'] = $cat;

	// change the sort order
	if ($sort!==null) {
		$args['orderby'] = $sort;
	}

	// Get the categories
	$cats = get_categories( $args );

	// check it's not empty
	if (empty($cats)) {
		return '';
	}

	// display a nofollow attribute ?
	$attr_nofollow = ($display_nofollow==true ? ' rel="nofollow"' : '');

	// add content
	if ($is_title_displayed==true && $cat == 0) {
		$return .= '<h4 class="wsp-categories-title">'.__('Categories', 'wp_sitemap_page').'</h4>'."\n";
	}
	$return .= '<ul class="wsp-categories-list">'."\n";
	foreach ($cats as $cat) {
		$return .= "\t".'<li><a href="'.get_category_link($cat->cat_ID).'"'.$attr_nofollow.'>'.$cat->name.'</a></li>'."\n";
		$return .= wsp_return_content_type_categories($is_title_displayed,$display_nofollow,$sort, $cat->term_id,$return);
	}
	$return .= '</ul>'."\n";

	// return content
	return apply_filters( 'wsp_categories_return', $return );
}

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