Are promises our only choice?
summary
Promises have eager evaluation, errors type as any, and let you omit catches, so this demo switches to fpts Task and TaskEither to get lazy evaluation and explicit error types, shows composing tasks with pipe to preserve referential transparency, sequences tasks so a failing step short‑circuits remaining work, uses remote-data to represent initial / pending / failure / success states for UI, and demonstrates Futures that run lazily and return a cancel function so long‑running requests can be unsubscribed.
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chapters (12)
- 0:00Async operations intro
- 5:17Promise limitations
- 6:00What is functional programming
- 8:32Functional alternatives
- 9:39Lazy evaluation with tasks
- 13:42Composable functions
- 18:06Referential transparency
- 20:34Short-circuiting with tasks
- 24:28Error handling with Either
- 35:14Async states with RemoteData
- 39:59Cancellable futures
- 47:15Conclusion and key takeaways
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