The Functional Fix: Kotlin Error Handling Made Elegant

on YouTube ↗41m

" summary

Refactors a procedural Kotlin HTTP-request matcher used in Specmatic into a Railway Oriented composition that returns an Either monad and chains via flatMap/fold; implements a small plumbing API — pipe/then/handleError — then replaces it with native Arrow KT flatMap composition. Example composes matchUrl → matchMethod → matchBody to pass the request along on success or short‑circuit with an error; takes about a week to prototype and is reused, but adds overhead so it pays off mainly for long chains (≈10 functions), not tiny ones.

AI-written summary · about

" chapters (8)

1. 0:00Introduction
2. 1:33The problem statement
3. 5:30Railway oriented programming
4. 10:06Code transformation journey
5. 25:03Understanding monads
6. 29:53Applying flatMap and fold
7. 36:25Refining the final solution
8. 39:09Q&A and conclusion

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