def fold_step
import bend-collections@1.0.0.0/src/containers/internal/intrusive_list.bend as IntrusiveListimport Base
148def fold_step(~S: Type, ~N: Data, ~V: Data, ~A: Type, ~C: Data, ~next: S -> N -> S & Maybe<&2, N>, ~value: S -> N -> S & V, ~fn: S -> C -> A -> V -> S & A, s: S, +node: N, +c: C, acc: A) -> S & (Maybe<&2, N> & A):
149 fold_step_1(~S, ~N, ~V, ~A, ~C, ~next, ~value, ~fn, node, c, acc, next(s, node))