def at_least_two

bend-collections@1.0.0.0 · src/containers/intrusive_doubly_linked_list.bend:49

import Base
import bend-collections@1.0.0.0/src/containers/internal/intrusive_list.bend as Impl

49# O(1) query: head exists and has a successor.
50def at_least_two(~S: Type, ~N: Data, ~H: Data, ~get_head: S -> H -> S & Maybe<&2, N>, ~next: S -> N -> S & Maybe<&2, N>, s: S, +h: H) -> S & Bool:
51  Impl.at_least_two(~S, ~N, ~H, ~get_head, ~next, s, h)