Datamapper object to array, with id as array key

gistfile1.php

/**
	 * Convert the entire $object->all array result set into an array of
	 * associative arrays.
	 * @see		to_array
	 * @param	DataMapper $object The DataMapper Object to convert
	 * @param	array $fields Array of fields to include.  If empty, includes all database columns.
	 * @param string $key_field Key Field array
	 * @return	array An array of associative arrays.
	 */
	function all_to_array($object, $fields = '', $key_field = '')
	{
		$result = array();

		if ( $key_field == '' )
		{
			foreach($object as $o)
			{
				$result[] = $o->to_array($fields);
			}
		}
		else
		{
			foreach($object as $o)
			{
				if ( ! is_array($fields) )
				{
					$result[$o->{$key_field}] = $o->{$fields};
				}
				else
				{
					$result[$o->{$key_field}] = $o->to_array($fields);
				}
			}
		}
		return $result;
	}