The Pierian Stream
summary
Argues that FS2 (with cats-effect) is best understood by a concrete pull model that diagrams pulls, outputs and done signals, letting one predict effect ordering (e.g., how repeat and evalMap interact) without diving into internals; demonstrates the ambiguity of naive intuition with a cat-eat/nap example and notes FS2 exposes over 100 operators. Uses FS2, Cats and Cats Effect as tools, shows the diagram approach composes and predicts side-effect sequences but admits concurrency, errors and resources need extra rules.
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chapters (23)
- 0:00Introduction
- 0:56Definition
- 2:28Data Processing and Events
- 6:09Stream Operators
- 8:47Stream Example
- 13:08Learning
- 17:59Mental Models
- 19:16Experimentation
- 22:09The Mental Model
- 25:18Substitution
- 27:50Evaluation and Substitution
- 28:24Equational Reasoning
- 29:32Example
- 32:50Finding a better model
- 34:24Pulling
- 35:46Downward Arrow
- 37:34Repeat Operator
- 38:30Compose Diagrams
- 39:08Start Diagrams
- 39:51Limitations
- 41:02Pull Model
- 41:52Pull Model Applications
- 42:47Resources
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