Definitions | P   Q, suptype(S; T), S T, x:A. B(x), Void, a < b, n+m, , A, False, A B, P  Q, P  Q, x:A B(x), P & Q, A c B, , can-apply(f;x), f^n, Top, if b then t else f fi , case b of inl(x) => s(x) | inr(y) => t(y), {x:A| B(x)} , b, x:A B(x), left + right, , Type, t T, s = t |