def bitw.last_set_none
import bend-osdev-algo@0.1.0.0/PROOF.bend as PROOFimport Base
import bend-osdev-algo@0.1.0.0/algo.bend as A
491def bitw.last_set_none(+n: Nat, +w: Word(n), e: {A.bitw.index(A.bitw.fls(n, w)) == None{} : Maybe<&2, Nat>}) -> {w == Word.zero(n) : Word(n)}:
492 bitw.fls_zero(n, w, bitw.index_none(A.bitw.fls(n, w), e))