PL/pgsql declaration of string / bit / number with given (variable!) length

Hi,

I have a PL/pgsql function that creates a certain bit string
based on the parameters. Things work fine if I use bit(10)
throughout the function. Now I'd like to return a bit string
with the given size "len", but that breaks with a syntax error:
       ret := B'0'::bit(len);LINE 1: SELECT  B'0'::bit( $1 )                           ^

Any suggestion how to return a (bit) string
of user-defined length ?

Thanks in advance,
Yours,
Steffen

CREATE OR REPLACE FUNCTION unarystr(   value integer,   len integer
) RETURNS bit(10) AS $$
DECLARE   ret bit(10);   one bit(10);
BEGIN   ret := B'0'::bit(10);   one := B'1'::bit(10);
   FOR num IN 0..value-1 LOOP      ret := ret | (one >>num);   END LOOP;   RETURN ret;
END;
$$ LANGUAGE plpgsql;


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IPB Halle                    AG Massenspektrometrie & Bioinformatik
Dr. Steffen Neumann          http://www.IPB-Halle.DE
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