| n ∈ used-ecs(wlar, m) ↔ (∃ m1. m1 < m ∧ wlar[m1].status = used ∧ wlar[m1].ec = n), wlar[m] = wl-entry(m2, stat), m < # wlar ⊦ n ∈ (stat = used ⊃ used-ecs(wlar, m) ++ m2;used-ecs(wlar, m)) ↔ (∃ m0. ¬ m < m0 ∧ wlar[m0].status = used ∧ wlar[m0].ec = n) |
n ∈ used-ecs(wlar, m) ↔ (∃ m1. m1 < m ∧ wlar[m1].status = used ∧ wlar[m1].ec = n), wlar[m] = wl-entry(m2, stat), m < # wlar, n ∈ (stat = used ⊃ used-ecs(wlar, m) ++ m2;used-ecs(wlar, m)) ⊦ ∃ m0. ¬ m < m0 ∧ wlar[m0].status = used ∧ wlar[m0].ec = n
n ∈ used-ecs(wlar, m) ↔ (∃ m1. m1 < m ∧ wlar[m1].status = used ∧ wlar[m1].ec = n), wlar[m] = wl-entry(m2, stat), m < # wlar, ∃ m0. ¬ m < m0 ∧ wlar[m0].status = used ∧ wlar[m0].ec = n ⊦ n ∈ (stat = used ⊃ used-ecs(wlar, m) ++ m2;used-ecs(wlar, m))