drop table if exists test_table;

CREATE TABLE test_table (a int);

create or replace function doit(r int, a int) returns bool
language plpgsql as $$
begin
  raise notice 'r = %, a = %', r, a;
  if (r = 10) then
    CREATE RULE make_noise AS ON DELETE TO test_table
	DO ALSO INSERT INTO test_table SELECT 2;
    raise notice 'made rule';
  end if;
  if (r = 20 and a = 1) then
    CREATE RULE make_noise_2 AS ON DELETE TO test_table
	DO ALSO INSERT INTO test_table SELECT 3;
    raise notice 'made rule 2';
  end if;
  return true;
end$$;

set plan_cache_mode to force_generic_plan;

DO $$
BEGIN
    FOR r IN 1..30 LOOP
        TRUNCATE test_table;
        INSERT INTO test_table SELECT 1;
        DELETE FROM test_table where doit(r,a);
    END LOOP;
END$$;

table test_table;