def bs.step0
import bend-osdev-algo@0.1.0.0/PROOF.bend as PROOFimport Base
import bend-osdev-algo@0.1.0.0/bsearch.bend as S
1097def bs.step0(c: Bool, +r: Nat, l: {Nat.is_lt(0n, S.bsearch.below.step(c, r)) == True{} : Bool}) -> {c == True{} : Bool}:
1098 match c:
1099 case True{}:
1100 {==}
1101 case False{}:
1102 Empty.absurd({False{} == True{} : Bool}, absurd.ft(l))