How can I merge multiple Streams into a higher level Stream?
import 'dart:async' show Stream;import 'package:async/async.dart' show StreamGroup;main() async { var s1 = stream(10); var s2 = stream(20); var s3 = StreamGroup.merge([s1, s2]); await for(int val in s3) { print(val); }}Stream<int> stream(int min) async* { int i = min; while(i < min + 10) { yield i++; }}See also http://news.dartlang.org/2016/03/unboxing-packages-async-part-2.html
prints
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You can use StreamZip in package:async to combine two streams into one stream of pairs, then create the C objects from that.
import "package:async" show StreamZip;...Stream<C> createCs(Stream<A> as, Stream<B> bs) => new StreamZip([as, bs]).map((ab) => new C(ab[0], ab[1]));
If you need to react when either Stream<A> or Stream<B> emits an event and use the latest value from both streams, use combineLatest.
Stream<C> merge(Stream<A> streamA, Stream<B> streamB) { return streamA .combineLatest(streamB, (a, b) => new C(a, b));}