def seq_at_f2
import bendtorch@1.3.0.0/main.bend as Bendtorchimport Base
847# Owned layer composition for dimensions read at run time. Each child record is opened once; each closure goes to
848# exactly one corresponding closure of the composite layer. The template-based Seq above keeps its existing laws.
849def seq_at_f2(-P1: Type, -P2: Type, -Y: Type, -Z: Type, -S1: Type, -S2: Type, p2: P2, fb: P2 -> Y -> Fwd<P2, Z, S2>, r: Fwd<P1, Y, S1>) -> Fwd<Two<P1, P2>, Z, Two<S1, S2>>:
850 match r:
851 case Fwd{p1, y, s1}: seq_f3(P1, P2, Z, S1, S2, p1, s1, fb(p2, y))