"Outperforming Imperative with Pure Functional Languages" by Richard Feldman
Why Hacker News recommends it
Recommended as the clearest explanation of why immutable data need not be slow, and as the introduction to Roc.
What it is
Richard Feldman explains how pure functional languages can match or beat imperative ones on performance. Compilers can turn immutable code into in-place mutation, avoiding naive copying. The talk draws on his work on the Roc language.
Recommended by 6 HN commenters across 6 different months, 2021 to 2025.
What Hacker News said
Recommends memco · 2021-11 · on “4x Smaller, 50x Faster”
> How would one optimize for immutability in this case, other than turning it back into mutability behind the scenes? Roc-lang, which is a functional, systems language in development uses something called opportunistic in-place mutation to do just that. Here's a video where the creator talks about it: [this video]
Recommends niels_bom · 2021-11 · on “4x Smaller, 50x Faster”
This talk by Richard Feldman about Roc (a new language) goed into why immutable does not necessarily mean slow and given enough attention can mean higher performance in certain cases: [this video]
Recommends aquadrop · 2022-02 · on “Haskell2020 Is Dead, but All Hope Is Not Lost (2019)”
Maybe [LINK] ? It's not production ready, I just saw nice talk by Richard Feldman [1] about it and it's inspired by Elm. [1] [this video]
Recommends Akronymus · 2022-06 · on “Ask HN: Functional vs. Imperative Implementation of Algorithms”
> Functional programming experts say that their code is efficient because the compiler translates it to an efficient representation on the CPU. They have TCO and other things. But they don't mutate data and hence every function call creates a new data in memory taking up space. How do they overcome that? By letting the compiler make assumptions. For example, consecutive map calls can be converted into a single one. If the data isn't shared with something else, the compiler can mutate it. MUCH easier to paralellize maps. As a starting point for those nitty grittys, this talk is probably as good as any [this video]
Recommends yashrk · 2023-11 · on “Roc – A fast, friendly, functional language”
If you are interested, «why yet another programming language?». The unique selling point of Roc is clever optimization to convert purely functional source code to deep-imperative fast machine code, while keeping all the correctness of functional algorithms. See this video of Richard Feldman for details — «Outperforming Imperative with Pure Functional Languages»: [this video] Among those clever optimizations: - static reference counting (no GC, like in Rust, but with no borrowing and borrow problems); - stack allocation of the data with no external links; - hidden («opportunistic») mutability even in the cases, where Haskell or Lisp will copy the value.
Recommends greener_grass · 2024-10 · on “Serialization Is the Secret”
1. Structural sharing - most data doesn't change so you create a copy that reuses much of the original structure 2. Garbage collection and lexical scopes - you clean up memory quickly and in batch 3. Compiler optimizations - you turn functional constructs into imperative ones that reuse and mutate memory at compile-time, where it is provably safe to do so Roc Lang might interest you: [this video]
Recommends greener_grass · 2025-02 · on “Roc rewrites the compiler in Zig”
We already have many great GC'd functional languages at that performance level. I first learned about Roc from this talk: [this video] That's a niche that is not currently filled (well, maybe MLTon) and that has me very excited! I'm sure I'm not alone here.
Cites yewenjie · 2022-02 · on “High-order Virtual Machine (HVM): Massively parallel, optimal functional runtime”
So many new programming languages coming up with clever features that makes me wish I could mix and match their core features while using libraries from more popular languages. Up and coming Languages I am excited about - 1. Roc - [this video] 2. Zig - [LINK] 3. Scopes - [LINK] 4. Gleam - [LINK] 5. Odin - [LINK] 6. Koka - [LINK] 7. Unison - [LINK]