The fused refold Seed => A, building no intermediate S (needs only Traverse[F]). coalg unfolds a seed into one typed layer; alg folds the layer's results (node-blind, like Cata). Definitionally ana(coalg).cross(cata(alg)). Stack-safe.
The fused refold Seed => A, building no intermediate S (needs only Traverse[F]). coalg unfolds a seed into one typed layer; alg folds the layer's results (node-blind, like Cata). Definitionally ana(coalg).cross(cata(alg)). Stack-safe.