User defined exceptions

Hello all!
Trying to emulate "named" user defined exception with:
CREATE OR REPLACE FUNCTION exception_aaa () RETURNS text AS $body$
BEGIN
return 31234;
END;
$body$
LANGUAGE PLPGSQL
SECURITY DEFINER
;

do $$
begin
raise exception using errcode=exception_aaa();
exception
when sqlstate exception_aaa()
then
raise notice 'got exception %',sqlstate;
end;
$$

Got:

ERROR: syntax error at or near "exception_aaa"
LINE 20: sqlstate exception_aaa()

I looks like "when sqlstate exception_aaa()" doesn't work.

How can I catch exception in this case?

--
Alex Ignatov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company

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