expand<R> method Null safety

HStream<Iterable<R>> expand<R>(
  1. Iterable<R> expander(
    1. T? input
    )
)

Implementation

HStream<Iterable<R>> expand<R>(Iterable<R> expander(T? input)) {
  return HStream<Iterable<R>>(expander(first), after.map((T item) => expander(item)));
}