How to display user-defined functions?

Hi,

Is there a way to display user-defined functions?  For example, if I define a
function using PL/pgsql, what tables do I query and in what way to learn that
the function exisits and further, what its defintion is? I can find functions
that return known types, eg getTimeStamp, below, shows up with '\df', however
functions defined returning type "opaque" do not show up, eq,
"exon_foreign_keys", below.

As a wish list, a command like, '\dF' to display functions I have defined,
including those returning opaque would be nice.

---------------------------------------------------
-- Listed by '\df' amongst many other functions
CREATE FUNCTION getTimeStamp() RETURNS timestamp AS '
DECLARE
    cur_time timestamp;
BEGIN
    cur_time = ''now'';
    RETURN cur_time;
END;
' LANGUAGE 'plpgsql';

--------------------------------------
-- Not listed by '\df'  or by any other means I can locate
CREATE FUNCTION exon_foreign_keys() RETURNS opaque AS '
DECLARE
    zhvt_row zhvt%ROWTYPE;
BEGIN
    IF NEW.zhvtID ISNULL THEN
        RAISE EXCEPTION ''zhvtID can not be NULL'';
    END IF;

    SELECT * INTO zhvt_row FROM zhvt WHERE zhvtID = NEW.zhvtID;
    IF NOT FOUND THEN
        RAISE EXCEPTION ''zhvtID = % is not in TABLE zhvt'' , NEW.zhvtID;
    END IF;
    RETURN NEW;
END;
' LANGUAGE 'plpgsql';

Thanks,
Mark

--
Mark Dalphin                          email: mdalphin@amgen.com
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