def prev
import bend-collections@1.0.0.0/src/containers/intrusive_links.bend as IntrusiveLinksimport Base
49def prev(s: Links, n: U32) -> Links & Maybe<&2, U32>:
50 Links{nexts, prevs, heads} = s
51 prev_got(nexts, heads, Array.get(U32, prevs, n))