Section Soundness.
Context {X: Const}.
Implicit Type (s: exp X).
Definition semtyping Gamma s A := forall gamma, G Gamma gamma -> E A (gamma • s).
Notation "Gamma ⊨ s : A" := (semtyping Gamma s A) (at level 80, s at level 99).

Lemma ordertyping_termination_steps Gamma n s A:
Gamma ⊢(n) s : A -> exists t, s ▷ t.