Async injection

on YouTube ↗01h 02m

" summary

Shows how to stop async leaking into the domain by treating C# async as a monad and injecting behavior into the Task<T> monad instead of changing domain signatures. Uses concrete C# tools: Task<T>, Lazy<T>, LINQ select/selectMany, a custom Maybe<T> and controller/repository examples. Refactors a restaurant reservation flow: move ReadReservations/Create to the boundary, keep MaitreD logic synchronous, return Maybe/Task wrappers, and compose with Select/Match. Result is deterministic domain logic, async where needed, and no leaked async in interfaces.

AI-written summary · about

" chapters (27)

1. 0:00Intro
2. 0:24Outline
3. 2:49Domain Model
4. 13:16Zen Buddhism
5. 14:19The XY problem
6. 16:07Monads
7. 17:57Structures
8. 21:38Functors
9. 22:14Lazy computation
10. 27:07Collections
11. 28:57Tasks
12. 31:17Semi containers
13. 31:47Novel of T
14. 38:01Composable helper functions
15. 39:16Example application
16. 47:47impure operations
17. 50:13leaky abstraction
18. 50:57post method
19. 53:19code changes
20. 55:11reservation
21. 56:08match
22. 56:21compiler warning
23. 56:48post method change
24. 57:12get better
25. 57:30pure function
26. 58:59removing IMHOD
27. 59:09wrapping up

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