Live data from Hacker News

Algebraic Effects in Practice with Flix

relax.software

1–10 of 55 posts

Re: Algebraic Effects in Practice with Flix

#3
I really want effects to shine and thrive, but since this is a very academic topic, only academic people engage with the research and it comes with academic pedantism, perfectionist worldview, strange attraction to beautiful consistency, etc. This automatically places effect research FAR from any practicality and grounded realism. 2 points, as examples: 1. Ever tried adding a simple print statement for debugging purposes while coding in effectful lang? compiler: "NNNOOOOO!!!! THIS IS AN ERROR; I WILL NEVER COMPILE THIS NONSENSE YOU __MUST__ SPECIFY CONSOLE EFFECT WAAARGHH!11" 2. multi-resumable stacks. how many times you really want to implement custom backtracking for multi resumable computations? this is such an obscure nonsensical use case that is hard to nearly impossible to solve efficiently, but everyone wants to support it. supporting this adds enormous complexity and kills any potential for performance. WHYYYYYYYYY. and yet they focus on this as a holy grail feature but whever there is a showcase they use synthetic "choice" example, lol.

Re: Algebraic Effects in Practice with Flix

#4

I really want effects to shine and thrive, but since this is a very academic topic, only academic people engage with the research and it comes with academic pedantism, perfectionist worldview, strange attraction to beautiful consistency, etc. This automatically places effect research FAR from any practicality and grounded realism. 2 points, as examples: 1. Ever tried adding a simple print statement for debugging purp…

To be fair, presumably debug printig could be "escaped" from the effect type checking if the designer of an effect system would want it. For instance, debug printig in Haskell completely sidesteps the need for the IO Monad and just prints in whatever context

Re: Algebraic Effects in Practice with Flix

#5
post #4

I really want effects to shine and thrive, but since this is a very academic topic, only academic people engage with the research and it comes with academic pedantism, perfectionist worldview, strange attraction to beautiful consistency, etc. This automatically places effect research FAR from any practicality and grounded realism. 2 points, as examples: 1. Ever tried adding a simple print statement for debugging purp…

To be fair, presumably debug printig could be "escaped" from the effect type checking if the designer of an effect system would want it. For instance, debug printig in Haskell completely sidesteps the need for the IO Monad and just prints in whatever context

yeah, most times its solved by side-stepping the strict type system and making an exception for debug prints. but this is not a real practical solution, this is a stupid workaround born from overinsistence on "beautiful" design choices.

Re: Algebraic Effects in Practice with Flix

#6
> Solving the “what color is your function” problem.

Eh. I currently use monads for my effects, and am open to the idea of language-based effects.

But this isn't a solution to the colour problem - it is the colour problem. The compiler stops you accidentally calling red from blue. If you want to do it deliberately, you change the caller from blue to red.

Re: Algebraic Effects in Practice with Flix

#7

I really want effects to shine and thrive, but since this is a very academic topic, only academic people engage with the research and it comes with academic pedantism, perfectionist worldview, strange attraction to beautiful consistency, etc. This automatically places effect research FAR from any practicality and grounded realism. 2 points, as examples: 1. Ever tried adding a simple print statement for debugging purp…

I’m sure default effects could handle this, just as Rust has some auto traits and default trait bounds. It doesn’t even have to be the full console i/o effect, it can be a specific debug effect that outputs to console in a dev build and to a file or devnull or whatever in release builds, or you could disable it in release builds and the compiler ensures there aren’t stray debug calls left, without needing a specific lint for that.

(Rust does have a similar problem in that debug printing requires the Debug trait bound which can be really annoying when writing generic code. Would be nice if there were a sprinkle of RTTI involved.)

Re: Algebraic Effects in Practice with Flix

#9
post #4

Earlier quoted context omitted.

To be fair, presumably debug printig could be "escaped" from the effect type checking if the designer of an effect system would want it. For instance, debug printig in Haskell completely sidesteps the need for the IO Monad and just prints in whatever context

yeah, most times its solved by side-stepping the strict type system and making an exception for debug prints. but this is not a real practical solution, this is a stupid workaround born from overinsistence on "beautiful" design choices.

It seems to me like a pragmatic compromise and very much a real solution. What would you consider a real solution that isn’t overinsisting on beautiful design choices?

Re: Algebraic Effects in Practice with Flix

#10
OCaml got experimental algebraic effects in version 5.0 (December 2022). Here is a tutorial: https://github.com/tanelso2/ocaml-effects-tutorial

Also from the tutorial: "Unlike Eff, Koka, Links, and other languages that support effect handlers, effects in Multicore OCaml are unchecked currently. A program that does not handle a performed effect fails with a runtime error."

Post reply on HN