def bitw.ffs_zero.h
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
266def bitw.ffs_zero.h(m: Nat, e: {A.bitw.ffs.step(False{}, m) == 0n : Nat}) -> {m == 0n : Nat}:
267 match m:
268 case 0n:
269 {==}
270 case 1n+k:
271 Empty.absurd({1n+k == 0n : Nat}, absurd.sz(1n+k, e))