php tree

<?php

//function build tree --- recursive
function show_tree( &$data, $point, $str ){
	//reset($data);
	$str .= "&nbsp;&nbsp;&nbsp;";
	while ( list( $index, $point_data ) = each( $data ) ){
		if ( $point_data[ 'parent_id' ] == $point ){
			echo $str.$point_data[ 'name' ].'<br>';
			unset( $data[ $index ] );
			show_tree( $data, $point_data[ 'id' ], $str );
			reset( $data );
		}
	}
}