Why Janet? (2023)

(ianthehenry.com)

172 points | by yacin 2 hours ago

23 comments

  • 1313ed01 44 minutes ago
    There is also fennel, earlier language originally by same developer, that is similar, but compiles to, and is fully implemented in, Lua. No standard library of its own so missing many nice things like the parser library from janet, but it is good for writing scripts for things that embed Lua.

    https://fennel-lang.org/

  • krinne 2 hours ago
    This post is refreshing - smells of the pre AI discussions on the internet. A new language, a new syntax, heavy debate with people who have spent years writing code. I think someone should start a community online where AI isnt allowed.
    • probably_wrong 1 hour ago
      > I think someone should start a community online where AI isnt allowed.

      In case you haven't followed the saga, the latest[1] digg.com relaunch failed because they couldn't deal with the bot onslaught [2]. Whoever finds a reliable way to keep AI out of an online community first is likely to become a very rich person.

      [1] Second-to-last, actually, seeing as there seems to be a new homepage right now.

      [2] https://www.techspot.com/news/111698-digg-relaunch-fails-two...

      • ponkpanda 33 minutes ago
        Perhaps requiring webauthn credential for any post/comment with a whitelist of permitted webauthn hardware devices which must have touch/interaction enabled.

        I'd have to read the FIDO specs, however the only place I've seen webauthn hardware pinning in the wild is with Azure AD/Entra which is ostensibly based on token GUID. If this is the only enforcement mechanism available, it's spoofable.

      • dwedge 51 minutes ago
        > In case you haven't followed the saga, the latest[1] digg.com relaunch failed because they couldn't deal with the bot onslaught [2]

        Given that they wrote their goodbye post using LLMs and gave up after such a short amount of time, I don't take that at face value the same way I don't believe AI layoffs

      • pbronez 11 minutes ago
        Isn’t the solution high-quality identity verification? There are piles of digital identity companies out there. They make money selling to banks for KYC compliance. Heck, there are background check as a service companies designed to add trust to gig economy platforms.

        I used to think that a small payment could accomplish the same thing, but X selling blue check marks proved that doesn’t help much. Well, at least it’s a much weaker signal than the previous curated version.

        The challenge is any barrier to entry high enough to discourage motivated spammers is also high enough to discourage casual users. That disrupts the network effects you’ve traditionally needed to bootstrap a social website.

        If I was trying to get a new social site off the ground right now, I would try:

        1) secure a good brand from the pre-AI era. Twitter, Digg, Friendster, MySpace. Something that motivates a first look.

        2) Require third party identity verification on sign up, configured so the social site is never the custodian of PII, though require enough demographics to support high-value advertising later. Verification is free to the user, ideally provide multiple verification options- one US and one EU at minimum.

        3) Target a few core communities and invest. Find the people who moderate historically great subreddits, were active in twitter communities during the good years, etc. get them in your platform. Maybe even pay them.

        That should be enough to tell you if it’s going to work or not.

      • geokon 1 hour ago
        lobste.rs uses a web-of-trust referral system. I guess it still involves a moderator killing off bad nodes, but it seems to scale well
        • dust-jacket 43 minutes ago
          yeah but I can't post there because I don't know anyone with an account and frankly CBA traipsing around looking for someone who has an account.

          does seem like more things will have to go this way though

          • ramon156 33 minutes ago
            +1, if anyone wants to help me I'd be honored. mail me at ramon(@)odeva(.)nl
    • 9dev 32 minutes ago
      > a community online where AI isnt allowed.

      This is something I think about a lot, especially how one could pull it off without tearing down anonymity online. Having some sort of "proof of humanity" is a hard problem to solve.

    • DoughnutHole 1 hour ago
      The amazing thing about AI is that you don’t even need AI superfans to shoehorn it into a conversation that doesn’t even touch on AI. Detractors will do it for them.
      • NuclearPM 59 minutes ago
        Yes, it’s similar to Trump. But that makes sense right? AI is changing the world drastically, and so is Trump and his fascist friends.
    • shevy-java 1 hour ago
      > a new syntax

      How is the syntax new?

      It looks like lispy - see the outer parens in the examples given.

      • embedding-shape 54 minutes ago
        Heh, every time you show a average developer lisp for the first time the reaction is the same. Little do they know conditionals, GC, REPLs, macros and more comes from the syntax and language dreamed up in the 50s/60s.
    • soomtong 2 hours ago
      It’s been a few months, but I built a tool by Janet lang to communicate with an LLM via HTTP. Of course, I probably had Claude Code write it for me. It turned out better than I expected.

      I was really impressed by how small the executable file was. I’d only ever done web development with Node.js up until then.

  • mackeye 6 minutes ago
    janet has replaced sh, python, awk, etc. for me, for system scripts over a certain length! it has a very fast startup time (on my system, 1.4ms via hyperfine vs. 1ms for dash) for scripts (not compiled executables), and its sh-dsl module allows typing shell commands very elegantly, like ($ cmda w x | cmdb y z). the ability to load an image to debug is a big help, too. i've started using it very recently but it's probably one of my favorite languages now, and the only other lisp i've used is mit scheme for sicp.
  • soomtong 14 minutes ago
    This document was really helpful when I first met Janet:

    https://janetdocs.org/tutorials

    https://janet.guide/ (the author's one)

  • ramblurr 1 hour ago
    Always nice to see janet getting some attention.

    shout out to one modern feature: sandbox

    "Disable feature sets to prevent the interpreter from using certain system resources. Once a feature is disabled, there is no way to re-enable it."

    https://janet-lang.org/api/misc.html#sandbox

  • xrd 17 minutes ago
    The author made these using Janet (discussed on HN in the past):

    https://bauble.studio

    https://toodle.studio

    Those two fascinating art tools got me very excited about Janet a while back.

  • uka 2 hours ago
    > But by allowing you to unquote literal functions, Janet makes it possible to write macros that are completely referentially transparent.

    These lisp guys really get excited over very abstract things. If you say this to an average person on the street they will probably try to run away.

    • fredrikholm 20 minutes ago
      > very abstract things

      A C macro with literals that lacks referential transparency:

        #define MULTIPLY(x, y) x * y
        int result = MULTIPLY(2 + 3, 4); // 14
      
      Not knowing what something means does not make it bad, which is what I'm assuming you meant given how you phrased your sentence.

      Having a shared language of patterns and problems that occur in programming is a good thing. Ridiculing such terminology on the basis of "that group of programmers sure are weird" is pointless and counter productive.

    • bryanrasmussen 2 hours ago
      you ever try to explain object oriented programming languages and their benefits to the "average person on the street"?
      • rambrrest 2 hours ago
        somehow i also never got the idea around these languages like lisp. I remember i studied them in school - but i quickly forgot and never got around to relearning it.
        • barrell 58 minutes ago
          It took me probably 5 years of writing Clojure before it clicked. Once you get used to structural editing and repl driven development, it’s really hard to go back to syntactic languages.

          It’s kind of like in treesitter style editing, where you can “swap these two arguments,” “select this function,” “wrap this in a try block” with a single keyboard command… but way more standardized and granular. Plus with the ability to execute anything you highlight

          All that and then you realize you can store code as data (since it’s just a data structure) and run data as code.

          I think most programmers don’t realize how arbitrary the difference is between code and data until they get used to using LISP.

        • xigoi 1 hour ago
          The idea is that instead of having to learn tens of different syntactic constructs with subtle and often arbitrary differences, you just have parentheses and use them to build everything.
          • embedding-shape 58 minutes ago
            This is such a undervalued benefit, once you've learned s-expressions, you can basically learn a bunch of languages without having to learn completely new syntax. It'll be slightly different, with different idioms and names, but a hell of a lot easier than doing the same across every "It's like C but 50% of the syntax is different actually" language out there, which is most of them.
            • jurip 20 minutes ago
              Is the syntax really the stumbling block for most languages? Would Rust's lifetimes or Swift's isolation rules be easier if they used more parens? Are the scoping rule differences between Emacs Lisp and Scheme easier to comprehend because the syntax is similar?
        • zelphirkalt 1 hour ago
          Probably depends on whom you are asking. For me the essence is (1) having functions or procedures as the basic building blocks, not classes. (2) Having all the utility and higher order functions you need to deal with the functions and procedures first idea. (3) Having a very powerful syntax, that allows great semantic editing and is never ambiguous. Oh and can actually be extended in useful ways, without having to wait for a committee to decide upon "the one syntax to rule them all".
    • prerok 1 hour ago
      Average programmer too /j

      Frankly, though, I think lispy community has benefited from being smaller. For example, even though the now ancient Design Patterns already warned programmers to prefer composition over inheritance, the OO programmers still created 15 levels deep hierarchies.

  • 0x0203 1 hour ago
    Seems some of the listed advantages for Janet would also apply for tcl (small/simple, easy to learn, embeddable, usable as a shell, great for domain specific languages). It would be interesting, to me at least, to see a fan of Janet compare the two.
    • embedding-shape 51 minutes ago
      I've only used Tcl briefly, mostly for automation which it's great at. But it's a Algol-like imperative language, doesn't have any type of macros and makes everything based on strings (which makes sense for automation) instead of lists, with all the tradeoffs that comes with.

      It seems easier to figure out what the similarities are, because I think they're pretty few, they seem to differ more than they are similar.

  • lindig 2 hours ago
    > Instead of regular expressions, Janet’s text wrangling is based around parsing expression grammars. Parsing expression grammars are simpler, more powerful, and more predictable than regular expressions.

    I would dispute that this is the case. In PEGs, alternatives are not commutative, unlike in regular expressions. This can lead to quite frustrating debugging. While a valid choice, the advantage over REs is overstated.

    • zelphirkalt 1 hour ago
      PEGs are just soooo much easier to read than regexes for anything more complex than a few words or single line matching. REs are a hammer that tempts people to see everything as a nail, but once one progresses beyond that phase one usually wants as few REs as possible.
    • xigoi 1 hour ago
      The non-commutavity is a feature, not a bug. It allows you to have clearly defined parsing for grammars that would traditionally be considered ambiguous.
    • petee 59 minutes ago
      "small peg tracer"[1] is really helpful for breaking down a PEGs operation

      [1] https://github.com/sogaiu/small-peg-tracer

    • bmn__ 1 hour ago
      Came here for this comment. Janet would score positively in my mind if the evolutionary dead-end PEG were replaced with a grammar parser that is known to work under all circumstances.
  • wodenokoto 1 hour ago
    I've been drawn into the Janet posts that surface every once in a while here on HN, but found the otherwise highly praised "Janet for Mortals", not being for mortals at all.
    • petee 58 minutes ago
      Personally I get hung up on the macro syntax being near the beginning, but there is so much valuable stuff past that
    • lelanthran 1 hour ago
      > I've been drawn into the Janet posts that surface every once in a while here on HN, but found the otherwise highly praised "Janet for Mortals", not being for mortals at all.

      I'm surprised: the language is very straightfoward, simple, very few rules to remember. It's a Lisp but with a very small surface area.

      I mean, compared to other languages, Janet really is easier to lean, so I'm surprised that the book for it is difficult (did not read the book, but familiar-ish with the language. I don't have anything but praise for it, TBH).

    • shevy-java 1 hour ago
      > not being for mortals at all.

      I had that with Haskell. Although, while Haskell is too hard for me, I actually like its syntax.

      Janet seems to be Lisp 2.0, so the syntax is lispy.

  • defrost 2 hours ago
    Previously (April 2023) | 140 comments: https://news.ycombinator.com/item?id=35539255
  • AHTERIX5000 38 minutes ago
    Does embedding Janet still lean on global state?
  • skeledrew 2 hours ago
    This got me thinking of Hy. I wonder how syntactically close they are; there might be an exploitable Python -> Hy -> Janet path here.

    [0] https://hylang.org/

    • rcarmo 1 hour ago
      I used Hy for a long time, then tried Janet, and ultimately realized that I wanted more batteries included but didn't want Python... So I forked https://github.com/rcarmo/go-joker and am tinkering with it until it does all I want.
  • 6LLvveMx2koXfwn 2 hours ago
    Maybe needs a (2023) in the title?
  • wolfi1 1 hour ago
    why is it called Janet? perhaps to prevent it to be identified with the acronym for Lots of Irritating Single Parenthesis?
    • petee 1 hour ago
      It was named after the sentient computer system in the TV show "The Good Place"

      A humourous clip: https://youtu.be/etJ6RmMPGko?si=W98LdG1jDdUCXsHV

    • xigoi 1 hour ago
      If it was called [Something] Lisp, Lisp enthusiasts would complain that it’s not a lisp because it does not use linked lists as the primary data structure.
    • Imustaskforhelp 1 hour ago
      I know that Lisp has lots of paranthesis and I don't have enough experience with Lisp at all.

      But from the looks of it, Janet has some great ideas like the one that @ramblurr shared here about sandboxing ("Disable feature sets to prevent the interpreter from using certain system resources. Once a feature is disabled, there is no way to re-enable it.")

      Lisp from my understanding is incredibly polarizing and many people love it and many people hate it and that's fine, but at a certain point wouldn't it feel repetitive for statement like this and I am unsure of how healthy discussion about programming concepts can be done this way.

      There are so many interesting things from lisp-y languages like Janet and Julia is technically lisp-y too and Julia's compilation to GPU is awesome and Nim too which can compile to C/C++/JS!

      It's just so many interesting concepts overall in programming that paranthesis don't seem a concern to me as the underlying concept can be translated to something else, like sandboxing feature, transpilation to GPU or multiple targets!

      And there are many unique concepts in non-lispy languages like golang (cross-compat, portability with static binaries), elixir (concurrency!) too.

      It's just good to see the amount of innovation within programming from all spheres of influence :-D

      • adrian_b 50 minutes ago
        While I do not like the excess of parentheses of LISP and similar languages, their syntax is very consistent and predictable. Moreover, while LISP has an excess of parentheses, it omits a greater number of commas that are required in many other programming languages.

        I am much more annoyed by the random syntax inconsistencies of most popular programming languages, which are either caused by original language design mistakes, or, more frequently, by the late addition of some features that were not planned in the original language, so they had to be squeezed in with the help of various ugly workarounds.

        While during the last years I have not used much LISP like languages, there have been times when I used them a lot, for several years, in scripting applications, e.g. the LISP variant of old AutoCAD, the Scheme-like scripting language of the Cadence EDA applications, or the scsh Scheme dialect that is usable for replacing UNIX shell scripts.

        In all cases, these languages allowed a greater productivity associated with rarer bugs than the more popular scripting languages, like Python, Perl, TCL, bash.

        While aesthetically I might prefer the look of a Python program, for solving a practical production problem I would prefer to write scripts in one of the LISP derivatives. Obviously, the productivity in various programming languages depends a lot on individual preferences and previous experiences.

        It should be noted by all those who believe that the LISP-derived languages have too many parentheses, that the C programming language and all languages with syntax derived from it, like Java or Rust, have a great excess of parentheses in comparison with the older languages that had better designed syntaxes, e.g. ALGOL 68 or IBM PL/I.

        For example, compare

          for (i = 1; i <= 100; i += 5) { ... }
        
        with

          for i from 1 to 100 by 5 do ... od
        
        or

          if ( ... ) { ... } else { ... }
        
        with

          if ... then ... else ... fi
  • gspr 2 hours ago
    The embeddability sounds very appealing. Does anyone have experience with using this somewhere one might traditionally reach for Lua?
    • xigoi 1 hour ago
      I have built a markup language with embedded scripting in Janet. I originally tried to use Lua, but found the verbosity extremely frustrating.
  • IshKebab 2 hours ago
    Pretty compelling, especially "Janet does not adhere to the ancient customs. CAR is called first. PROGN is called do. LAMBDA is fn, and SETQ is def." - a sign of good sense for sure!

    How fast is it?

    Also my main objection to Lisps is still the horrible bracket syntax. Yes it's unambiguous and easy to parse, but it's HORRIBLE to read and edit. I wish this project had been a success (or something similar to it): https://readable.sourceforge.io/

    Also I don't think static typing is really optional for me at this point.

    • setopt 2 hours ago
      > Pretty compelling, especially "Janet does not adhere to the ancient customs. CAR is called first. PROGN is called do. LAMBDA is fn, and SETQ is def." - a sign of good sense for sure!

      Just FYI, many of these are also done in Scheme and its derivative Racket. They kept lambda (but even Python did that), but progn -> begin, setq -> set!, car -> first, and so on.

      > Also my main objection to Lisps is still the horrible bracket syntax. Yes it's unambiguous and easy to parse, but it's HORRIBLE to read and edit.

      I have pretty mixed feelings at this point. I don’t mind it for normal programming, but when I do numerical programming (physics models, etc.) you often get extremely long and verbose expressions that are IMO difficult to parse compared to the math-like infix operator notation used in other languages.

      • aeonik 2 hours ago
        I'm starting to prefer the s expression syntax when dealing with tree structures like json.

        I wonder if we were raised on tree based algebra if math would be easier to do, or harder.

        Like, solve for x.

           (= (+ (* 2 x) 3) 11)
           (= (* 2 x) (- 11 3))
           (= (* 2 x) 8)
           (= x (/ 8 2))
           (= x 4)
        
        Though this isn't too bad.

            (= (+ (pow x 2)
                  (pow y 2))
               (pow r 2))
    • adrian_b 45 minutes ago
      Actually not all those are ancient customs, and not all that Janet uses is newer.

      In the first description of the language LISP, from March 1959 (AIM-008), John McCarthy had used the names "first" and "rest", instead of what later will be called "CAR" and "CDR".

      The names of "CAR" and "CDR" appear to have come from the students who worked at the practical implementation of the LISP interpreter on an IBM 704, and unfortunately we have remained stuck with them, like also with other features that were intended only for a temporary use, until being replaced in the "final version" (which was abandoned).

    • xigoi 1 hour ago
      > Also my main objection to Lisps is still the horrible bracket syntax. Yes it's unambiguous and easy to parse, but it's HORRIBLE to read and edit.

      I use Parinfer, which allows me to edit Janet as if it was an indentation-based language.

    • graemep 2 hours ago
      Syntax is not that important to me. I prefer Python style indentation, but its really not that important - its just something to get used to for me.

      Is static typing that important for a scripting language? From the intro to the book:

      > And to be clear, I’m not going to try to convince you to bet your next startup on Janet, or even to use it in any sort of production setting. But I think it’s an excellent language for exploratory programming, scripting, and fun side projects.

    • zelphirkalt 41 minutes ago
      Out of those renames, I agree with car->first and progn->do. setq is ugly, but I think using def is maybe questionable. lambda I would have just kept the same.
    • e12e 1 hour ago
  • anthk 1 hour ago
    Luxferre.top has some Janet based softwrae.
  • shevy-java 1 hour ago

        (defn foo [first & rest] ...)
    
    So basically Lisp 2.0.

    Although, this here is a good idea:

    "pass values from compile-time to run-time"

    Would be nice if some kind of "scripting" language be as fast as a compiled language, but without ruining the syntax. Just about 99% of the languages that are shown, have a horrible syntax. Syntax is not everything, but most language designers don't understand that syntax also matters. So tons of horrible languages emerge. Nobody will use those languages, so 99% of them will die off quickly.

    • xigoi 1 hour ago
      What would be a better syntax according to you? I have found Janet’s syntax very pleasant to work with as opposed to JavaScript, Lua or even Python.
    • Imustaskforhelp 1 hour ago
      can't there theoretically be a language which transpiles to Janet to get all the benefits without additional paranthesis too?

      Not sure if such transpilation would have a perf hit though, I hope somebody responds who knows about it more.

      I don't deny that syntax matters itself too but there are some ideas of janet like sandboxing and other features which seem to me to be worth implementing in other languages too.

      Personally, I would be really interested in a language like lua/wren which can transpile to Janet too.

      • petee 51 minutes ago
        I guess you could transpile direct to Janet bytecode, and performance would be in theory the same as native Janet?
  • makach 1 hour ago
    Excellent. Although I suspect the author of the programming language invented this Janet for all the perfect puns. Yes, Janet. No. Janet.
  • xuzhenpeng 22 minutes ago
    [flagged]
  • rohitsriram 47 minutes ago
    [flagged]