def balance.get

bend-kit-collections@0.1.4.1 · PROOF.bend:886

import Base
import bend-kit-collections@0.1.4.1/LAWS.bend as Laws
import bend-kit-collections@0.1.4.1/omap.bend as O

886def balance.get(
887  ~K: Data, ~V: Data, ~cmp: K -> K -> Cmp, ~refl: Refl(~K, ~cmp), ~eq: Eq(~K, ~cmp),
888  ~flip: Flip(~K, ~cmp), ~trans: Trans(~K, ~cmp),
889  +lb: Maybe<&2, K>, +ub: Maybe<&2, K>, +x: K, +k: K, +v: V, +lo: O.OMap<K, V>,
890  +hi: O.OMap<K, V>,
891  el: {Laws.bounded(~K, ~V, ~cmp, lo, lb, Some{k}) == True{} : Bool},
892  eh: {Laws.bounded(~K, ~V, ~cmp, hi, Some{k}, ub) == True{} : Bool}
893) -> {g(~K, ~V, ~cmp, O.OMap.balance(K, V, k, v, lo, hi), x)
894      == g(~K, ~V, ~cmp, O.OBin{0, k, v, lo, hi}, x) : Maybe<&2, V>}:
895  +wl = (O.OMap.size(K, V, lo) + 1 : U32)
896  +wh = (O.OMap.size(K, V, hi) + 1 : U32)
897  balance.if.get(~K, ~V, ~cmp, ~refl, ~eq, ~flip, ~trans, U32.is_gt(wh, (3 * wl : U32)),
898    U32.is_gt(wl, (3 * wh : U32)), lb, ub, x, k, v, lo, hi, el, eh)