merge<T> static method
Merges the events from streams
into a single single-subscription stream.
This is equivalent to adding streams
to a group, closing that group, and
returning its stream.
Implementation
static Stream<T> merge<T>(Iterable<Stream<T>> streams) {
var group = StreamGroup<T>();
streams.forEach(group.add);
group.close();
return group.stream;
}