My question is simple: Why does Elm not rewrite List.map f >> List.map g into List.map (f >> g)? Because the thing is, this optimization can be seen in Java streams, (which is neither a lazy nor a pure functional language) yet it does not happen in Elm. Why is that?

[image] wolfadex: I thought for certain that’d be in elm-review-simplify 2.0.7 It’s not part of elm-review-simplify because this is not a simplification 100% of the time in terms of readability. a |> List.map toX |> List.map toY may be more readable than a |> List.map (toX >> toY) e…

It’s also fairly straightforward to write a library that does this in user land .

Transducers seems to be quite similar to iterators like Iter - elm-iter 1.0.0 for the purpose of computing multiple transformations before reducing. Do you know of good resources explaining the fundamental differences? I feel like transducers are more powerful since I remember reading about those wh…

Fundamentally there seems to be more than one way to skin a cat . In the broader view you’re gonna go somewhere between the simplicity of the for loop and the efficiency of SQL depending on your needs in terms of optimisation, composition and predictability. I think the cool thing about transducers…

[image] Lucas_Payr: Because the thing is, this optimization can be seen in Java streams, (which is neither a lazy nor a pure functional language) yet it does not happen in Elm. Why is that? In Java it’s not a compile level optimisation- it’s just normal Java code that is written to be lazy. T…

Lazy evaluated map

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wolfadex November 30, 2021, 1:21am 2

I thought for certain that’d be in elm-review-simplify 2.0.7 but I don’t see it listed. At the very least I think I’ve seen @jfmengels mention it in passing.

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Lazy evaluated map

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