fact: Fixpoint size (t : Te) := match t with | Var _ => 0 | Fun _ => 0 | App u v => 1 + max (size u) (size v) | Lam _ u => 1 + size u end.
imports: Coq(FSets Structures.OrderedType) CoLoR(LogicUtil BoolUtil VecUtil FSetUtil NatUtil RelUtil SN SetUtil)