Custom category list display for WordPress

cat-list-example.php

<?php
/*
Plugin Name: Get Terms Example
Plugin URI: http://pmg.co
Description: Get a list of all the categories and format them pretty like for output
Version: n/a
Author: Christopher Davis
Author URI: http://pmg.co/people/chris
License: Creative Commons/GPL2
*/

add_action( 'init', 'wpse25157_init' );
function wpse25157_init()
{
	add_shortcode( 'ref-list', 'wpse25157_ref_list' );	
}

function wpse25157_ref_list()
{
	// very hackish get_terms call with the 0 as a string to return top level terms
	$cats = get_terms( 'category', array( 'parent' => '0' ) );
	if( ! $cats || is_wp_error( $cats ) ) return;
	$out = '<div id="ref-list">' . "\n";
	foreach( $cats as $cat )
	{
		$out .= sprintf( 
			'<p class="lit-author"><a href="%s">%s</a> (%s)</p>',
			esc_url( get_term_link( $cat ) ),
			sanitize_term_field( 'name', $cat->name, $cat->term_id, 'category', 'display' ),
			sanitize_term_field( 'count', $cat->count, $cat->term_id, 'category', 'display' )
		);
		
		$out .= "\n"; // add some newlines to prettify our source
		
		$children = get_term_children( $cat->term_id, 'category' );
		if( $children && ! is_wp_error( $children ) )
		{
			foreach( $children as $child )
			{
				$child = get_term( $child, 'category' );
				if( is_wp_error( $child ) ) continue;
				$out .= sprintf( 
					'<p class="lit-work"><a href="%s"><em>%s</em></a>. %s (%s)</p>',
					esc_url( get_term_link( $child ) ),
					sanitize_term_field( 'name', $child->name, $child->term_id, 'category', 'display' ),
					esc_attr( $child->description ),
					sanitize_term_field( 'count', $child->count, $child->term_id, 'category', 'display' )
				);
				$out .= "\n"; // prettifying newline
			}
		}
	} // end of the foreach( $cats as $cat ) loop
	$out .= "</div>\n";
	return $out;
}