def AP.tree_get

bend-osdev-array@0.1.0.1 · PROOF.bend:1209

import Base
import bend-osdev-array@0.1.0.1/array.bend as A

1209def AP.tree_get(-T: Data, +d: Nat, +t: AP.Tree<T>, +hp: {A.Arrays.is_perfect(T, d, AP.build(T, t)) == True{} : Bool}, +hd: {Nat.is_lt(d, 32n) == True{} : Bool}, +i: U32) -> {List.get(&2, T, A.Arrays.leaves(T, AP.build(T, t)), A.Arrays.index(d, i)) == Some{AP.get_top(T, t, i)} : Maybe<&2, T>}:
1210  +sh = U32.shln(1, d)
1211  +j = AP.mask(sh, i)
1212  %Equal.sym(U32, AP.size(T, t), sh, AP.size_perf(T, d, t, hp)) : {List.get(&2, T, A.Arrays.leaves(T, AP.build(T, t)), A.Arrays.index(d, i)) == Some{AP.get_v(T, t, _, AP.mask(_, i), AP.z(_, AP.mask(_, i)))} : Maybe<&2, T>}
1213  AP.get_leaves(T, d, t, j, AP.z(sh, j), {==}, hd, hp, AP.index_lt(d, i))