Using EXIT and labels to exit blocks of statements

Hi, My novice question is – I’d like to use EXIT statement to exit a block of statements. I copied an example from pg 809 of postgresql 8.4 documentation but received

Following error. Just want to know correct way to use label. Thanks very much.

 

ERROR:  label does not exist at or near "ablock"

LINE 15:   EXIT ablock; -- causes exit from the BEGIN block

                ^

 

DROP FUNCTION IF EXISTS test_exit();

CREATE OR REPLACE FUNCTION test_exit()

RETURNS void AS

$BODY$

 

DECLARE

               x integer :=0;

               stocks bigint := 100100;

              

<<ablock>>

BEGIN

               -- some computations

               IF stocks > 100000 THEN

                              EXIT ablock; -- causes exit from the BEGIN block

               END IF;

               -- computations here will be skipped when stocks > 100000

 

END;

 

$BODY$

 

LANGUAGE 'plpgsql' VOLATILE

COST 100;

ALTER FUNCTION test_exit() OWNER TO postgres;