Except, of course, that the descent condition is false for all r tuples where r.mitm == 'r3` (since there is no t.mitm == 'r3') hence the corresponding output r is a single null tuple.
Except, of course, that the descent condition is false for all r tuples where r.mitm == 'r3` (since there is no t.mitm == 'r3') hence the corresponding output r is a single null tuple.