proposition: Lemma typing_add x y z: x +ₑ y =ₑ z ∈ E -> Gamma__deq ⊢₂(2) addEQ x y z : alpha → alpha → alpha.
proof: Proof. intros; unfold addEQ; split; cbn [fst snd]; autotype. Qed.
imports: RelationClasses Morphisms List Lia Init.Nat Setoid Undecidability.HOU(calculus.calculus second_order.diophantine_equations systemunification nth_order_unification)