def rh.wb

bend-kit-collections@0.1.4.1 · PROOF.bend:1421

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
import bend-kit-collections@0.1.4.1/nat_order.bend as Ord

1421def rh.wb(
1422  -K: Data, -V: Data, lo: O.OMap<K, V>, +k: K, +v: V, +hi: O.OMap<K, V>,
1423  +wbl: {WB(K, V, lo) == True{} : Bool}, wbh: {WB(K, V, hi) == True{} : Bool},
1424  heavy: Ord.LE(1n+Nat.mul(3n, W(K, V, hi)), W(K, V, lo)),
1425  alm: Ord.LE(W(K, V, lo), Nat.add(3n, Nat.mul(3n, W(K, V, hi))))
1426) -> {WB(K, V, Laws.g_rot_hi(K, V, k, v, lo, hi)) == True{} : Bool}:
1427  match lo:
1428    case O.OTip{}:
1429      Empty.absurd({WB(K, V, Laws.g_rot_hi(K, V, k, v, O.OTip{}, hi)) == True{} : Bool}, Ord.tiph(W(K, V, hi), heavy, w_pos(K, V, hi)))
1430    case O.OBin{s, +lk, +lv, +ll, +lh}:
1431      rhp.wb(K, V, Nat.is_lt(W(K, V, lh), Nat.mul(2n, W(K, V, ll))), k, v, lk, lv, ll, lh, hi,
1432        {==}, wbl, wbh, heavy, alm)