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Can you write an equivalent piece of code that shows why Rust wins here with more familiarity and leveraging the ecosystem? With compilers I don't think there i

Can you write an equivalent piece of code that shows why Rust wins here with more familiarity and leveraging the ecosystem? With compilers I don't think there is a huge amount of using the ecosystem. I think what TFA does is a good case study in trying to be objective: write it both ways and compare.

nu11ptr 3y ago
I'm just saying a compiler is a program, and while the more important things are heavy algorithm related, supporting libraries like those for error handling, etc. all still matter and add up. No problem if you disagree - just my perspective. This isn't so much an objective thing as it is a personal opinion.
- brmgb 3y ago
  Personally, it’s not so much that I disagree. It’s more that Ocaml has a top notch ecosystem for compiler writing. That’s probably by far its strongest point with library like Menhir having few equivalent in different ecosystem. Not that there is anything wrong with Rust if you are ready to pay the price of having so much low level things to deal with.
  - hardwaregeek 3y ago
    Can you explain what Menhir does better than other parser frameworks? For what it's worth, I'm not a huge fan of parser frameworks. I tend to prefer hand written parsers, either via a combinator library or fully manually. Rust has a pretty darn good ecosystem too btw. chumsky for parsing, rowan for syntax trees, salsa for incremental computation, miette for errors, inkwell/walrus for code generation.
    - brmgb 3y ago
      It can generate elegant and efficient parsers for LR(1) grammars. > I tend to prefer hand written parsers, either via a combinator library or fully manually. That’s common with people used to languages which provide poor parser generators.
      - hardwaregeek 3y ago
        What makes them more elegant than the average parser? How’s the error recovery? Can you parse into high fidelity syntax trees efficiently? I don’t know of many production compilers that use parser generators
        klodolph 3y ago
        You use the generated parser as a platform for experimentation. If you know the language, and you have a bunch of users, and you are writing a parser for it, by all means, write a parser by hand and give it the best error recovery that you can muster. If you are developing a language and want to do a bunch of experiments, it pays dividends to use a parser generator. And then there is the whole space of DSLs and mini-languages you encounter, where beautiful error messages are a nice-to-have, but you would rather ship a generated parser and move on to more important work. It’s easy to focus on compilers from the perspective of familiar languages like writing compilers for Rust or for OCaml, but you may end up writing a compiler that gets used by a much smaller number of people, for smaller tasks.
        hardwaregeek 3y ago
        That's great and I agree for these use-cases a parser generator makes sense. But that doesn't answer my question about what makes these parsers particularly elegant. Nor does it seem to be a benefit specific to Mehnir, since any parser generator has the quick iteration speed. I don't mean to blame you for that; you are answering a question about something that you did not say. But I find it frustrating that Mehnir seems to be cited as this fantastic cornerstone of the OCaml ecosystem when I haven't been presented with a good example of how it's better than any other parser generator. Not just my parent comment (who also decided to cast aspersions on my knowledge), but others in the OCaml community too.
        klodolph 3y ago
        I didn’t intend to answer your question—your comment had multiple aspects to it and I am responding to one part of it, rather than every single part of it. My main take on the “which language do I write my compiler in” conversation is that some of the various code transformation passes are just more convenient to write in a language which makes it easy to use both mutation and garbage collection, which puts OCaml above both Rust and Haskell. I think parsing is an easier problem to solve in the first place.
    - arcticbull 3y ago
      Wow those library recommendations are fantastic, especially Chumsky. Thanks for sharing.
      - hardwaregeek 3y ago
        Yeah chumsky is fantastic, albeit with some rough compile errors and some unsafe. Still my favorite parser library by far and I’ve used a bunch by now.
wredue 3y ago
There was nothing objective about the article. The moment I saw seemingly random new lines in the rust for no reason, I knew there was going to be a “line counts!!!!” Sentence. When there was, I stopped reading because it was apparent that all matter of objectivity is completely missing. I don’t even like rust.
- reikonomusha 3y ago
  It would be nice if somebody could offer what they consider to be an idiomatic Rust solution to this very routine problem in compilation if they believe the author is being intentionally deceiving. The Rust and OCaml code from the article looked decent to me. m
  - deleted 3y ago
    [deleted]
  - timeon 3y ago
    > The Rust and OCaml code from the article looked decent to me > RefCell<u32> I'm not sure.
    - stouset 3y ago
      For the uninitiated, this is a completely harmless choice. But it suggests a potential lack of understanding of some pretty fundamental parts of Rust.
    - foldr 3y ago
      Although I think the implementation of the gensym function is broken, the article does explain that it wasn’t possible to use &mut u32 because multiple references to the value were required. It would be more idiomatic to use Cell rather than RefCell, but there’s nothing really wrong with using RefCell as far as I can see.
  - tyg13 3y ago
    I don't think anyone was claiming the author was being intentionally deceiving, just that they're not very good at writing idiomatic Rust. The first thing I'd suggest, as someone who's done their fair share of Rust compiler dev, is to stop using `Box` and `Ref` everywhere. Terms should not own their child terms; the idiomatic way to handle this is to use an arena and typed IDs, and pass a reference to the arena when you need access to the underlying data from the ID.
deleted 3y ago
[deleted]

nu11ptr 3y ago

I'm just saying a compiler is a program, and while the more important things are heavy algorithm related, supporting libraries like those for error handling, etc. all still matter and add up. No problem if you disagree - just my perspective. This isn't so much an objective thing as it is a personal opinion.

brmgb 3y ago
Personally, it’s not so much that I disagree. It’s more that Ocaml has a top notch ecosystem for compiler writing. That’s probably by far its strongest point with library like Menhir having few equivalent in different ecosystem. Not that there is anything wrong with Rust if you are ready to pay the price of having so much low level things to deal with.
- hardwaregeek 3y ago
  Can you explain what Menhir does better than other parser frameworks? For what it's worth, I'm not a huge fan of parser frameworks. I tend to prefer hand written parsers, either via a combinator library or fully manually. Rust has a pretty darn good ecosystem too btw. chumsky for parsing, rowan for syntax trees, salsa for incremental computation, miette for errors, inkwell/walrus for code generation.
  - brmgb 3y ago
    It can generate elegant and efficient parsers for LR(1) grammars. > I tend to prefer hand written parsers, either via a combinator library or fully manually. That’s common with people used to languages which provide poor parser generators.
    - hardwaregeek 3y ago
      What makes them more elegant than the average parser? How’s the error recovery? Can you parse into high fidelity syntax trees efficiently? I don’t know of many production compilers that use parser generators
      - klodolph 3y ago
        You use the generated parser as a platform for experimentation. If you know the language, and you have a bunch of users, and you are writing a parser for it, by all means, write a parser by hand and give it the best error recovery that you can muster. If you are developing a language and want to do a bunch of experiments, it pays dividends to use a parser generator. And then there is the whole space of DSLs and mini-languages you encounter, where beautiful error messages are a nice-to-have, but you would rather ship a generated parser and move on to more important work. It’s easy to focus on compilers from the perspective of familiar languages like writing compilers for Rust or for OCaml, but you may end up writing a compiler that gets used by a much smaller number of people, for smaller tasks.
        hardwaregeek 3y ago
        That's great and I agree for these use-cases a parser generator makes sense. But that doesn't answer my question about what makes these parsers particularly elegant. Nor does it seem to be a benefit specific to Mehnir, since any parser generator has the quick iteration speed. I don't mean to blame you for that; you are answering a question about something that you did not say. But I find it frustrating that Mehnir seems to be cited as this fantastic cornerstone of the OCaml ecosystem when I haven't been presented with a good example of how it's better than any other parser generator. Not just my parent comment (who also decided to cast aspersions on my knowledge), but others in the OCaml community too.
        klodolph 3y ago
        I didn’t intend to answer your question—your comment had multiple aspects to it and I am responding to one part of it, rather than every single part of it. My main take on the “which language do I write my compiler in” conversation is that some of the various code transformation passes are just more convenient to write in a language which makes it easy to use both mutation and garbage collection, which puts OCaml above both Rust and Haskell. I think parsing is an easier problem to solve in the first place.
  - arcticbull 3y ago
    Wow those library recommendations are fantastic, especially Chumsky. Thanks for sharing.
    - hardwaregeek 3y ago
      Yeah chumsky is fantastic, albeit with some rough compile errors and some unsafe. Still my favorite parser library by far and I’ve used a bunch by now.

wredue 3y ago

There was nothing objective about the article. The moment I saw seemingly random new lines in the rust for no reason, I knew there was going to be a “line counts!!!!” Sentence. When there was, I stopped reading because it was apparent that all matter of objectivity is completely missing. I don’t even like rust.

reikonomusha 3y ago
It would be nice if somebody could offer what they consider to be an idiomatic Rust solution to this very routine problem in compilation if they believe the author is being intentionally deceiving. The Rust and OCaml code from the article looked decent to me. m
- deleted 3y ago
  [deleted]
- timeon 3y ago
  > The Rust and OCaml code from the article looked decent to me > RefCell<u32> I'm not sure.
  - stouset 3y ago
    For the uninitiated, this is a completely harmless choice. But it suggests a potential lack of understanding of some pretty fundamental parts of Rust.
  - foldr 3y ago
    Although I think the implementation of the gensym function is broken, the article does explain that it wasn’t possible to use &mut u32 because multiple references to the value were required. It would be more idiomatic to use Cell rather than RefCell, but there’s nothing really wrong with using RefCell as far as I can see.
- tyg13 3y ago
  I don't think anyone was claiming the author was being intentionally deceiving, just that they're not very good at writing idiomatic Rust. The first thing I'd suggest, as someone who's done their fair share of Rust compiler dev, is to stop using `Box` and `Ref` everywhere. Terms should not own their child terms; the idiomatic way to handle this is to use an arena and typed IDs, and pass a reference to the arena when you need access to the underlying data from the ID.

deleted 3y ago

[deleted]