def obs_list
import bend-collections@1.0.0.0/src/containers/bitset.bend as Bitsetimport Base
import bend-collections@1.0.0.0/src/containers/types/bitset.bend as E
508def obs_list(r: Bitset & List<&2, Nat>) -> Bitset & E.Obs:
509 (s, xs) = r
510 (s, E.OList{xs})