def right_nth

bend-collections-laws-crypto@1.0.0.0 · proofs/lib/array.bend:164

import Base
import bend-collections-laws-crypto@1.0.0.0/proofs/lib/list.bend as LL
import bend-collections-laws-crypto@1.0.0.0/spec/lib/common.bend as SC

164def right_nth(-T: Data, +p: Nat, +l: Tree<T>, +r: Tree<T>, +j: Nat, +pl: {perfect(T, p, l) == True{} : Bool}, +le: {Nat.is_le(SC.pow2(p), j) == True{} : Bool}) -> {SC.nth(T, SC.append(T, slots(T, l), slots(T, r)), j) == SC.nth(T, slots(T, r), Nat.sub(j, SC.pow2(p))) : Maybe<&2, T>}:
165  %slots_length(T, p, l, pl) : {SC.nth(T, SC.append(T, slots(T, l), slots(T, r)), j) == SC.nth(T, slots(T, r), Nat.sub(j, _)) : Maybe<&2, T>}
166  LL.nth_append_right(T, slots(T, l), slots(T, r), j, len_le(T, p, l, j, pl, le))