public function mapResult(ResultIterator $result) {
		//check numer of rows returned
		if ($result->countRows() == 0)
			return null;
	
		//get result column types
		$this->columnTypes = $result->getColumnTypes();
		
		//build type handler list
		if ($this->defaultClass != 'stdClass' || !is_null($this->resultMap))
			$this->buildTypeHandlerList();
		
		//get row as an object and map using its model
		return $this->map($result->fetchObject());
	}