Fun with Algebraic Effects – From Toy Examples to Hardcaml Simulations

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82 pointsweinzierl3 comments

Chapter 9 and section 10.7 of this book show some interesting (and to me unexpected) uses of effects in Ocaml and how they compare to implementations based on monads:

https://lukstafi.github.io/curious-ocaml/new_book.html

The dscheck model-checker is another interesting application of effects: https://github.com/ocaml-multicore/dscheck

Thanks, I've been meaning to delve into algebraic effects and it seems OCaml is the only mainstream language that actually implemented them.

That books seems very interesting in general, thank you for sharing!

Then again, I am a bit skeptical since the author also credits Claude Opus 4.5 and GPT-5.2. Both models got released in November/December last year, which makes me wonder: Was this book written in only 2 months, i.e. mostly by AI?

EDIT: No. Turns out the book is much older and only recent changes were done with the help of LLMs, https://github.com/lukstafi/curious-ocaml/commits/main/?afte... .

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