go-samber-ro

Create an observable with operators like Just, FromSlice, or RangeWithInterval, then chain transformations using typed Pipe2 through Pipe25 functions with operators like Map, Filter, and FlatMap. Subscribe with NewObserver handling onNext, onError, and onComplete, or use Collect for synchronous slice results.

Use samber/lo for finite slice transforms like Map, Filter, and Reduce on data already in memory — it is synchronous and eager. Use samber/ro when data arrives over time from infinite streams, multiple async sources, or when you need retry, timeout, backpressure, and stream combination.

Cold observables start an independent execution for each subscriber and are the default. Hot observables share one execution across subscribers, created via Share, ShareReplay, Connectable, or natively hot subjects like PublishSubject and BehaviorSubject.

Use PublishSubject for event broadcasting without history, BehaviorSubject when subscribers need the current state, ReplaySubject to replay the last N values, AsyncSubject for only the final value on completion, and UnicastSubject for exactly one buffered consumer.

Infinite streams without termination conditions keep running forever. Bound them with Take(n), TakeUntil(signal), Timeout(d), or context cancellation via ThrowOnContextCancel, and call Unsubscribe on subscriptions you no longer need.

Chain Timeout with a duration, then RetryWithConfig specifying max attempts, delay, and backoff multiplier, and finally Catch to fall back to an alternative observable like a cache. This replaces manual retry loops with declarative operators.