def append_nil
import bend-osdev-crypto@0.1.0.0/PROOF.bend as PROOFimport Base
468def append_nil(xs: List<&2, U32>) -> {xs == List.append(&2, U32, xs, Nil{}) : List<&2, U32>}:
469 match xs:
470 case Nil{}:
471 {==}
472 case Con{h, t}:
473 %append_nil(t) : {Con{h, t} == Con{h, _} : List<&2, U32>}
474 {==}