def record
import bend-collections@1.0.0.0/src/containers/bitlist.bend as Bitlistimport Base
import bend-collections@1.0.0.0/src/containers/types/bitlist.bend as E
321def record(acc: List<&2, E.Obs>, r: Bitlist & E.Obs) -> Bitlist & List<&2, E.Obs>:
322 (s, o) = r
323 (s, Con{o, acc})