def kept_batch_head
import bendvy-ecs-core@0.1.0.4/event_family_runtime.bend as EventFamilyRuntimeimport Base
import bendvy-ecs-core@0.1.0.4/event_runtime.bend as Ev
38def kept_batch_head(~P:Data,~F:Type,rest:F -> F & List<&2,Ev.Batch<P>>,tick:Nat,returned:F & List<&2,P>) -> F & List<&2,Ev.Batch<P>>:
39 match returned:
40 case (family,records):kept_batch_returned(~P,~F,tick,records,rest(family))