PLPGSQL function to search function source for a list of terms

Here is a plpsql function I put together to search db functions in
schemas other than pg_catalog and information_schema. Not the greatest
of coding, but it might help someone else trying to solve the same
issue I was having: to search all public functions for a list of
terms. Sample usage is below the code, as are some sample results.

Any changes/improvements/critcisms appreciated. (or even a better version!)

[works in pg version 8.4, not in 8.2 -- not sure about 8.3]

create or replace function search_public_functions(p_search_strings
TEXT, p_case_insensitive BOOLEAN, OUT function_name TEXT, OUT
matching_terms TEXT) RETURNS SETOF RECORD AS
$body$
declare
x RECORD;
qry TEXT;
v_match BOOLEAN := 'false';
v_matches TEXT;
v_search_strings TEXT := p_search_strings;
v_case_insensitive BOOLEAN := p_case_insensitive;
v_funcdef TEXT;
begin
/* v_search_strings is a list, pipe-separated, exactly what we
want to search against.
NOTE: works on postgresql v8.4
example:
select function_name,matching_terms from
search_public_functions('crosstab|intersect|except|ctid',true);
*/

if (v_case_insensitive IS NOT FALSE) then
v_case_insensitive := TRUE;
end if;

qry := 'SELECT n.nspname||''.''||p.proname||''
(''||pg_catalog.pg_get_function_arguments(p.oid)||'')''::TEXT as
funcname,
(select pg_catalog.pg_get_functiondef(p.oid))
as funcdef,
p.oid as funcoid
FROM pg_catalog.pg_proc p
LEFT JOIN pg_catalog.pg_namespace n ON n.oid =
p.pronamespace
WHERE pg_catalog.pg_function_is_visible(p.oid)
AND n.nspname <> ''pg_catalog''
AND n.nspname <> ''information_schema''
AND NOT p.proisagg
ORDER BY 1';

if (p_case_insensitive IS TRUE) then
v_search_strings := LOWER(v_search_strings);
end if;

for x in execute qry loop
v_match := 'false';
function_name := null;
v_funcdef := null;

select into v_match x.funcdef ~* v_search_strings;

if ( v_match IS TRUE ) then
v_matches := null;
v_funcdef := x.funcdef;
if (p_case_insensitive IS TRUE) then
v_funcdef := LOWER(v_funcdef);
end if;
select array_to_string(array_agg(val),',')
into v_matches from (select distinct
array_to_string(regexp_matches(v_funcdef, v_search_strings ,'g'),',')
as val) as y2;

function_name := x.funcname;
matching_terms := v_matches;
RETURN NEXT;
end if;
end loop;
end;
$body$ language plpgsql SECURITY DEFINER;

select function_name,matching_terms from
search_public_functions('crosstab|intersect|except|ctid',true);

function_name | matching_terms
--------------------------------------------------------------+----------------
public.array_intersect (anyarray, anyarray) | intersect
public.cant_delete_error () | except
public.crosstab2 (text) | crosstab
public.crosstab3 (text) | crosstab
public.crosstab4 (text) | crosstab
public.crosstab (text) | crosstab
public.crosstab (text, integer) | crosstab
public.crosstab (text, text) | crosstab
public.find_bad_block (p_tablename text) | ctid,except