fanout<U> method
Implementation
$async.Result<Pair<V, U>> fanout<U>($async.Result<U> Function() other) =>
flatMap((outer) => other().map((v) => Pair(outer, v)));
$async.Result<Pair<V, U>> fanout<U>($async.Result<U> Function() other) =>
flatMap((outer) => other().map((v) => Pair(outer, v)));