27 ms·

Why I’m Learning Perl 6

433 points by mpalme 9y ago

aduitsis 9y ago
Read the article, very informative. Pleasantly surprised to find out that it doesn't mention at all language traits like syntax, but focuses on the features of Perl6's underlying VM, specifically MoarVM.
- agumonkey 9y ago
  Indeed, a GILless bytecode VM is worth a look.
  - rurban 9y ago
    GIL less yes, but not lockless. The previous perl6 VM, parrot, had lockless threads, scaling linearly per native core. MoarVM even needs to lock on hash or array accesses, which is certainly not state of the art.
    - oconnor663 9y ago
      How did parrot write arrays from multiple threads without a lock somewhere in there?
      - bigleagueposter 9y ago
        The parrot threads didn't communicate with each other and you could wait until all of them finished. They provided a tiny subset of the functionality real threads offer but in a more efficient way.
      - rurban 9y ago
        You deferred updates to the owner via scheduler, with high prio, and continue. parrot threads are lock free but not wait free. The NQP compiler needed to know about threaded writes and schedule the update, with a semaphore, while the other threads continue. What MoarVM got better was everything else. The GC, the calling convention, the OO (6model), the jit. I was on my way to fix all the parrot damage done from the previous decade, because this would have enabled all architectures and proper threading for perl6, but then perl6 decided to kill it and go with Moar. And spread a lot of lies on threads.
        pierrebai 9y ago
        I fail to see how using a semaphore to schedule work in another thread is "lock-free."
        rurban 9y ago
        Because you wait but you don't lock. And the wait is not 100x of an instruction, normally it's the same time as for one single instruction. Writes are fast and atomic, because there's no lock. Only the writer needs to wait a bit, not any other thread. Google for lock-free vs wait-free
- petre 9y ago
  Well, it should have mentioned Perl6 uses rational number math instead of floating point. I think this is a big advantage, since you can do more precise calculations using just the core language.
ricardobeat 9y ago
Crystal (http://crystal-lang.org http://crystal-lang.org) has fibers and channels. Current implementation isn't multi-threaded but it's being worked on. So you'll get that concurrency + nice syntax + types + a wonderful stdlib. EDIT: as seen in other responses, options abound: Python 3, Elixir, D, Dart and more all have built-in concurrency primitives, not to mention that discarding nodejs because of "callback hell" is at this point laughable.
- giancarlostoro 9y ago
  Not sure about channels but D has fibers. It is one reason / benefit of why vibe.d[0] was made. [0]: http://vibed.org/features http://vibed.org/features Note: Vibe.d is a web frameworks as well as a networking stack for D. If you're even remotely curious about D or do any web development I recommend you check out Vibe.d it is quite impressive (at the very least to me). Edit: There's apparently jin.go / Go.d: https://github.com/nin-jin/go.d https://github.com/nin-jin/go.d
- holydude 9y ago
  I am really,really excited about Crystal. I wish it success but I am afraid if the rails shops and big companies do not start using it it will be too little too late.
  - goatlover 9y ago
    That would be unfortunate. I really like Crystal as a fast, typed alternative to Ruby, but I also prefer Ruby as a language to Go or even Elixir, which not everyone does.
_pmf_ 9y ago
> Concurrency is hard and if you want M:N thread multiplexing (i.e. WEB SCALE CODE, where application threads aren’t pinned to pthreads) your options today are precisely Erlang, Go, .NET, and Perl 6 Why mention .NET here? Async code in .NET works with a dispatcher thread (-pool) under the hood, which is nothing like the greenish threads that the other systems offer. Am I missing something?
- pjmlp 9y ago
  TPL, tasks are the greenish threads you mention. You can also just call Windows fibers directly, if feeling adventurous.
- poooogles 9y ago
  I mean core async in Clojure works the same, would you say it's the same? It might not be under the hood, but as perceived to the programmer it is?
- deleted 9y ago
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- deleted 9y ago
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throwaway7645 9y ago
Perl6 is indeed a very nice language that I've been watching for a few years. As soon as the performance beats Python and the stability is solid I'll probably switch over from Python...there's just a lot there.
- b2gills 9y ago
  I have seen examples where the naive Perl 6 implementation is faster than the equivalent C code. (The one I'm thinking of is probably owing to Spesh and the JIT, but I forget what it was about) Here's an example where a naive Perl 6 version is going to beat the pants off of the naive version in another language: Find the sum of all integers from 10 to 1000000 inclusive. In Perl 6: say [+] 10 .. 1000000 the [+] is a left fold using the &infix:«+» operator (&infix:«+» is left associative) This finishes almost immediately. (It also does so if the endpoint is 10¹⁰⁰⁰ or more) The reason is if you use the built in version of the &infix:«+» operator, it calls the sum method on the Range object. That particular method knows how to calculate the sum on the Range without iterating through the values. If you modify the &infix:«+» operator lexically it won't take that shortcut. This also works the same if you wrote it like this: say Range.new(10,1000000).reduce(&[+]) (There is syntax to omit either or both endpoints with both ways to create a Range) There are plenty of areas where Rakudo Perl 6 is slower than I would like, but for many uses it is fast enough.
  - slackersc 9y ago
    That's pretty cool! I started trying to learn perl6 and write my first interesting program. I have a copy of 'ray tracing in a weekend' and am trying to translate the basic ray tracer from c++ to perl6. It's remarkably slow right now.. It takes 1.5 minutes to generate an image. I tried to do the same thing in Julia and it takes 1.5 seconds. So I guess I must be doing something wrong!
    - raiph 9y ago
      Maybe it'd be fun to hack on https://github.com/raydiak/pray https://github.com/raydiak/pray?
IceDane 9y ago
> Why is this important? Concurrency is hard and if you want M:N thread multiplexing (i.e. WEB SCALE CODE, where application threads aren’t pinned to pthreads) your options today are precisely Erlang, Go, .NET, and Perl 6. I guess the author doesn't know about Haskell? The concurrency story for Haskell is great, and using the right library, you can literally just define types for the routes for your backend and then ask it to generate JS for your frontend.
- aaron-lebo 9y ago
  edit: dumb snark, but the replies are useful
  - IceDane 9y ago
    No need for the snark. This isn't fanboyism, though I gladly admit that I'm fond of Haskell. I'm not just namedropping Haskell "just because". He claims those languages are the only one that have green threads. He's wrong. I corrected that.
    - aaron-lebo 9y ago
      You're right, that was overly snarky, but your post does come off as use Haskell -> magic. The concurrency stories for Erlang and Go are front and center, very well defined, and obvious. How do you get similar functionality in Haskell (specifically, what libraries do what you are talking about)?
      - IceDane 9y ago
        The library I was referring to is called servant[1]. It's a library for writing backends and clients in Haskell. I mentioned it because he said something about "webscale", but it doesn't have anything to do with concurrency. The go-to library for nice Haskell concurrency is probably async[2], which you can combine with stm[3] for very nice guarantees. If you're interested, there is a very nice, free book[4] on the subject. [1] https://haskell-servant.github.io/ https://haskell-servant.github.io/ [2] https://www.stackage.org/package/async https://www.stackage.org/package/async [3] https://www.stackage.org/package/stm https://www.stackage.org/package/stm [4] http://chimera.labs.oreilly.com/books/1230000000929/index.html http://chimera.labs.oreilly.com/books/1230000000929/index.ht...
SeanDav 9y ago
Without a "Major" sponsor, or a "Rails" type killer application, Perl 6, or indeed any language, will struggle to get significant traction. It is of course possible to gain slowly over time, but with numerous languages competing, that path may be a dead-end.
- forinti 9y ago
  Perl 6 still has to overcome Perl 5, which is everywhere and is a great language. I never get around to using Perl 6 because 5 is already there in every Linux distribution.
  - bjd2385 9y ago
    I wish Linux distros shipped with more recent language versions, e.g. Python 3.6 and Perl 6 in addition to just 3.4/5 and 5. I understand that it's not their job to try and push people to update their language skills, but it'd be nice to have access to them right off the bat if they feel like it.
    - riffraff 9y ago
      python3.x vs 2.x is nowhere near the jump from perl5 to perl6. It's basically a different language that shares some things, with few users. It would be nice to see it shopped, but you might as likely wish distribution shipped with crystal or nim.
      - bjd2385 9y ago
        Hey, it was a wish lol. I know we live in the real world here
    - chriswarbo 9y ago
      The difference between Python minor versions (e.g. 3.4 to 3.6) is tiny compared to the difference between Perl 5 and 6. From what I've seen, the difference between Python 2.x and 3.x is tiny compared to the Perl 5/6 change.
mapcars 9y ago
It's terrible that you put Erlang on a list with other languges/VMs. >There’s no GIL, so unlike Those Other Languages There is no GIL in EVM as well, but playing with the words you make it look like "all are the same". This does not deserve top HN and just stupid. If your Perl6 VM is _so_ great, why didn't you mention anything about what's really important like preemptive scheduling which has been Erlang's unbeatable feature since the beginning? Less hype and more details, please.
- macintux 9y ago
  FWIW, the author is very well-known and respected in the Erlang world for his work on Chicago Boss. Any perceived slights against Erlang are likely unintentional.
- b2gills 9y ago
  The author of the article likely hasn't dug much into the VM code yet. https://github.com/MoarVM/MoarVM/#feature-overview https://github.com/MoarVM/MoarVM/#feature-overview
jypepin 9y ago
why is everybody saying they are put off by Go? Did we pass the "trend" phase and now it's cool to say go sucks?
- kalekold 9y ago
  lol no generics
- notamy 9y ago
  Tongue-in-cheek answer: lol no generics :) To be serious, in my circle of developer-friends, we feel that it tries to be TOO simple, and disagree with some of the decisions of how the language works (ex. seemingly endless `if err != nil { return nil, err }` type things)
  - codegladiator 9y ago
    I always find it a bit funny when dev's try to put a label of "too simple" on a language. How would your friends label "brainfuck" ? Too simple because it has very limited number of identifiers or Too hard because accomplishing anything is nightmare ?
    - kazagistar 9y ago
      Simple is not the opposite of hard. The opposites are complex and easy.
- FungalRaincloud 9y ago
  I don't know about others, but I personally have always seen Go as an internal language for Google. This made me feel like it was appropriate for projects that I personally control, but unlikely to be useful in a career. That's really just a feeling, though, and I recognize that if everyone felt like I do, it would make Go a niche language that was actually probably pretty lucrative to know. So I wouldn't say I'm put off by it, so much as the balance of factors hasn't tipped in favor of learning it yet.
  - 9y ago
rastapasta 9y ago
thanks for touching the heart of an old perlmonk :)
krylon 9y ago
Can anyone recommend a good book on Perl 6? Are there any (even bad ones)? Right now I feel the major reason that keeps me from investing time in Perl 6 - besides adoption by distros - is the lack of a good book, like the Lama and the Camel book for Perl 5. It's kind of frustrating after having waited so long.
- totalperspectiv 9y ago
  This one is 'in progress' https://www.learningperl6.com/ https://www.learningperl6.com/ Looking at the Perl 6 website, there are a few more coming along as well. https://perl6.org/resources/ https://perl6.org/resources/
  - krylon 9y ago
    Nice, thank you very much!
  - cutler 9y ago
    ... but nothing from Larry Wall. I don't get it. Perl 6 without a "Programming Perl 6" (O'Reilly or Pragmatic) will just delay adoption.
- sigzero 9y ago
  http://greenteapress.com/wp/think-perl-6/ http://greenteapress.com/wp/think-perl-6/
- perlgeek 9y ago
  https://perl6book.com/ https://perl6book.com/ gives an overview of Perl 6 books, and how they differ. Enjoy!
- krylon 9y ago
  To all who answered: Thank you very, very much!!!
- _delirium 9y ago
  > adoption by distros This has improved, and I think most distros now ship Rakudo (Perl6 on MoarVM). At least: Debian, Ubuntu, Fedora, and Arch do.
StevePerkins 9y ago
> Concurrency is hard and if you want M:N thread multiplexing (i.e. WEB SCALE CODE, where application threads aren’t pinned to pthreads) your options today are precisely Erlang, Go, .NET, and Perl 6. Putting aside the "web scale" jokes (http://www.mongodb-is-web-scale.com/ http://www.mongodb-is-web-scale.com/), this statement is still absurd. Every major language, or at least the ones that matter for backend development, has support for thread multiplexing / coroutines / fibers, whatever. Perhaps not in the core language syntax or standard library. But it's easy to implement with native code, and so SOMEONE has implemented it in a library if the language has an FFI. Java, and all of the other JVM-based languages in turn, have Quasar (http://docs.paralleluniverse.co/quasar/ http://docs.paralleluniverse.co/quasar/). Ruby has support for primitive fibers baked into the standard language (https://ruby-doc.org/core-2.1.1/Fiber.html https://ruby-doc.org/core-2.1.1/Fiber.html), and likewise community gems with more robust functionality like Quasar. Python 3 likewise has this out of the box (https://www.python.org/dev/peps/pep-0492/ https://www.python.org/dev/peps/pep-0492/). The list goes on and on: https://en.wikipedia.org/wiki/Coroutine#Programming_languages_with_native_support https://en.wikipedia.org/wiki/Coroutine#Programming_language....
- rootlocus 9y ago
  I'd like to know why people are downvoting this.
  - dragonwriter 9y ago
    Probably because it treats a high-level feature (M:N threading) as equivalent to a lower-level feature (coroutines) and then compounds that by treating as equivalent languages where the former is built into the core with ones where the latter is available as a third-party library, all as a way of dismissing the value of languages where the former feature is built in to the core, and layered with scorn and derision on top of being doubly wrong. Now, I preferred correction to downvoting, but I can easily see why others would choose downvoting.
  - thehardsphere 9y ago
    People often downvote anything that's remotely negative, even if it is true or merely a critical question.
fundabulousrIII 9y ago
I'll stick with Tcl if I'm going to use a glue language that has green thread like functionality and an event loop. early choices were tcl or perl: went Tcl and never looked back. As far as web development in perl..well have fun convincing everyone on the node.js and python bandwagons to move 'back' to perl. Glad it works for you.
- totalperspectiv 9y ago
  I hadn't heard of Tcl before but it looks awesome! What do you find its ideal use cases to be?
  - forinti 9y ago
    I use Tcl/Tk from time to time and it always seems the easy choice when I need a simple GUI and also need to make an executable for Windows (which is trivial with Freewrap). Some of the things I've written are: a simple standby order input app, a Forms/Reports compiler (sends file to server, waits for response and informs user), and a Ghostscript wrapper for merging lots of PDFs into one file.
    - totalperspectiv 9y ago
      Awesome! I'm definitely going to be keeping it in mind as little projects come up that could use a GUI.
  - williadc 9y ago
    TCL is really great for throwing syntax errors at runtime, having no real data structures, and an inconsistent API!
    - logicchains 9y ago
      Better than throwing syntax errors at compile time; saves the programmer time. By the time errors happen, it's the customer's problem instead.
  - 9y ago
ainar-g 9y ago
Can Perl6 merge all of its generated VM code into one "package"? One of my favourite things about Go is that you can statically compile everything and then deployment basically becomes scp.
- rlpb 9y ago
  ...and then deployment basically becomes scp. And security updates for your deployment become...what?
  - sherr 9y ago
    Rebuild and scp the whole lot again? Not necessarily a big deal.
    - rlpb 9y ago
      Rebuilding by pulling in all your dependencies from the Internet again? That's not something I want to do when the clock is ticking to get a security update out. What if some random third party dependency is hosted somewhere that is down, or has been pulled? And how do I know I have to rebuild in the first place? You'll probably tell me that there are tools to help deal with this. I'm sure there are. My point is that it isn't as simple as "scp".
    - xutopia 9y ago
      Or doing patches. Copy the file locally... apply the patch... restart process.
- hpcjoe 9y ago
  I find it somewhat humorous that more than 25 years on, we are effectively reverting to static linking and bundling [1]. Way ... way back in the day, the argument was it would save memory, encourage reuse, etc. While some of this may have been true, it also gave rise to dynamic library hell. Reuse was overshadowed by incompatible versions, or API changes between versions that became the stuff of legends. This would make a great study in how the ROI was completely overshadowed by risk considerations not considered at the outset. Of course, saving memory was a huge issue in the days when 1GB RAM was considered gigantic. So maybe the cost was worth it. [1] https://scalability.org/2017/03/what-is-old-is-new-again/ https://scalability.org/2017/03/what-is-old-is-new-again/
pmontra 9y ago
On a sidenote > or Nginx or Node.js without the callback cacciatore. What's a cacciatore in this context? It means hunter in Italian. Probably something messy if it means the same as callback hell.
- credit_guy 9y ago
  I read it as a short version of chicken cacciatore, which is a dish with an appearance that may look messy.
  - Sean1708 9y ago
    That makes sense I suppose, it's a cacciatore made with callbacks instead of chicken.
- dagw 9y ago
  cacciatore is a style of rustic stew in Italian cooking.
  - riffraff 9y ago
    "alla cacciatora" is the name of the style in Italian, that somehow got mangled in english. Kinda like "gabagool" which is effectively an american only name for an italian product we call "capocollo". pmontra is italian, hence the confusion.
  - pmontra 9y ago
    I would have bet that cacciatore was about food. To be pedantic, that's "alla cacciatora" but I won't be picky with Italian food terms outside Italy, it's good advertising anyway (I'm an Italian in Italy.)
    - orbitur 9y ago
      > To be pedantic, that's "alla cacciatora" but I won't be picky with Italian food terms outside Italy It's good that you won't be picky, since you're arguing against decades of "cacciatore" for Italian Americans. ;)
Rjevski 9y ago
My personal issue with Perl is how much of a mess the syntax is (10 different ways of doing the same thing), and the lack of a standard library (CPAN is not a viable replacement).
- IslaDeEncanta 9y ago
  Why is CPAN not a viable replacement? It has always been perfectly viable for me.
  - Rjevski 9y ago
    CPAN packages are written by thousands of different people with varying styles (cf. the issue with 10 different ways of doing the same thing), quality standards and maintenance schedules. In Python I can expect the standard library to be consistent and be maintained as part of the core language. Now I don't mean that everything has to be in the standard library (I'm fine with the database access libraries being third-party for example), but in Perl even the most basic stuff like exceptions is only on CPAN and there are again multiple packages to choose from..
    - b2gills 9y ago
      Unfortunately for Python is that many/most of the modules that are included were written when the language was fairly new, so at a time when nobody was an expert in the language. Which means that perhaps for many of them there is a better module out in the ecosystem that almost nobody uses because they have one extra step to install them. If you want something close to that in Perl 6, just install Inline::Python and you can use all of those “batteries included” with Python as if they were modules written in Perl 6. Exceptions in Perl 6 are much easier to deal with than they are in Perl 5.
- yellowapple 9y ago
  I'll take 10 different ways to do the same thing with different approaches over one "true" way with no flexibility any day. Perl gives the programmer a lot of rope to work with. Whether one ties that rope into a drawbridge or a noose is the programmer's choice. Also, CPAN is fantastic and widely supported. I really wish more languages would follow its example, especially when it comes to package namespaces.
grondilu 9y ago
> Guess what it outputs? Nothing! Just kidding, you’ll see a lot of distressed messages from tasks that passed out wait for the phone to ring, and woke up wearing someone else’s OS thread. Well, as a matter of fact I really got no output at all :(
- libeclipse 9y ago
  > Actually, the program will output nothing if you’re using a release of Perl 6 prior to Rakudo Star 2017.07; a caching bug previously caused $*THREAD.id to report an out-of-date value.
pvdebbe 9y ago
I like writing bash scripts a lot and perl is a natural step-up with powerful libraries to use. As others have said, the major obstacle for me has been the lack of great literature.
- yellowapple 9y ago
  There's lots of literature out there for Perl 5 (like the so-called "Camel Book"). Perl 6 literature is pretty scarce, though.
  - throwaway7645 9y ago
    There is 2 out now and many in development. So really not that bad.
    - cygx 9y ago
      2? It's 5 now! https://www.apress.com/us/book/9781484228982 https://www.apress.com/us/book/9781484228982 http://shop.oreilly.com/product/0636920065883.do http://shop.oreilly.com/product/0636920065883.do https://deeptext.media/perl6-at-a-glance/ https://deeptext.media/perl6-at-a-glance/ https://deeptext.media/migrating-to-perl6 https://deeptext.media/migrating-to-perl6 https://www.amazon.com/Learning-program-Perl-Getting-programming-ebook/dp/B07221XCVL https://www.amazon.com/Learning-program-Perl-Getting-program...
      - throwaway7645 9y ago
        No idea the other ones came out so fast :)
- dmytrish 9y ago
  For small tasks I enjoy aesthetics of small dedicated Unix tools (grep, sed, awk, cut, sort) working together much more. Perl tries to be everything at once, still mysteriously lacking interactive REPL out of the box. Yes, Python is more heavyweight for scripting, but it pays in the long term with better maintenance and tooling for big scripts.
libeclipse 9y ago
Thing that really gets me about perl is the syntax, it's horrendous. No other reason, that's all. Just the syntax.
- tankenmate 9y ago
  Blame Aho, Weinberger, and Kernighan. Oh and Larry :)
  - tannhaeuser 9y ago
    Why are the awk guys to blame for Perl syntax?
    - tankenmate 9y ago
      > (It's sorta like sed, but not. It's sorta like awk, but not. etc.) Guilty as charged. Perl is happily ugly, and happily derivative. Usenet article <1992Aug26.184221.29627@netlabs.com> (1992) -- Larry Wall
      - vgy7ujm 9y ago
        I don't see the problem here... those are good tools and Perl have those tools power in the core language++ Good stuff if you ask me.
  - fnord123 9y ago
    The good thing about awk is that it's limited. So you know when to stop using it and move to use a different language when your requirements exceed the comfort zone of awk. Larry Wall came and made a language inspired by awk that doesn't give feedback on when you're out of the comfort zone. This lets you make a mess before you know what you've done (aka technical debt). The same problem 'that killed Smalltalk and could have killed ruby' too (thanks, Bob Martin).
- Scarblac 9y ago
  It's _different_. But working for a few years with Perl 5, it really grew on me. It could use a good "Perl: The Good Parts" book, I guess. I haven't looked at Perl 6 yet, don't know if that's better or worse. Too many other things to do, and I don't think I'll ever work with Perl professionally again, that ship has probably sailed.
contingencies 9y ago
Great quote on perl5... In #devops is turtle all way down but at bottom is perl script. - @devopsborat
- tripa 9y ago
  I like how the original was agnostic, yet you interpreted as perl5 :-)
  - contingencies 9y ago
    I think it's common knowledge that perl6 is basically rare in deployment, whereas perl5 scripts are everywhere in legacy systems. Former CPAN author myself.
Steeeve 9y ago
I hate perl6. I hate it because I tried to get involved in the project early on, and it led me down the Haskell rathole. I don't know what Haskell looks like today, but a decade or more ago it was the hardest language to pick up that I had ever experienced. It was as if I had a solid background in latin languages and I was trying to pick up Chinese based on a handful of tutorials written by a tourist on the back of a napkin. But it has been a decade and I am truly impressed with what it has turned into. Unfortunately, it has to re-gain mindshare as if it was starting from scratch. It might be a little bit harder actually, because there are a variety of scripting languages these days that are easy to learn, and there are still more than a few people who actively don't like Perl. I really liked this slideshow: http://tpm2016.zoffix.com/#/ http://tpm2016.zoffix.com/#/ It gives a good review of Perl6 from early 2016. The video is an hour and a half, but it only takes a few minutes to scan through the slides and find the interesting pieces. (left and right arrow to navigate the slides)
- txdv 9y ago
  I looked quickly through the slides and saw that perl has now grammar build in the language... Truly an interesting feature
  - perlgeek 9y ago
    It is. You can build recursive descending parsers with a declarative syntax, and all the benefits from having it in OO (role composition, inheritance). Here is a working grammar for INI config files: https://github.com/tadzik/perl6-Config-INI/blob/master/lib/Config/INI.pm#L5 https://github.com/tadzik/perl6-Config-INI/blob/master/lib/C...
  - dmytrish 9y ago
    Is the language itself a good place for parsing/grammar handling? I could not even find in the standard documentation which kind of parsers it supports, is it LR(k)? LL(k)? Any CFG? What parsing method does it use: recursive descent, shift-reduce, something more general like CYK/Earley algorithms? How does it handle ambiguities? It turns out that `grammar` keyword generates recursive descent parsers and anything even a bit fancier still requires a dedicated parsing library.
Verdex_2 9y ago
For some reason, when I started my software engineering career I got it into my head that I needed to learn as much as I could about programming languages. I learned ruby, perl5, python, lisp, forth, ml, ocaml, scheme, haskell, r, c#, java, lua, c++, factor, idris, asm, erlang, prolog, rust, d. But that wasn't quite enough because haskell and idris kept on talking about complicated type theory stuff. So I also learned lambda calculus, type theory, set theory, domain theory, topology, category theory, information theory, sub-structural logic. What I'm trying to say is that I'm not afraid of learning new things. Even if they seem hard or esoteric. When I heard that perl6 was ready, I took a look. I like the idea of a lot of what is present in the language (hey look, a grammar engine, that's neat). But ultimately, I decided that it was too much stuff that I would have to learn. Maybe that's just a perception problem on my part, but I have to think that they have some sort of problem if someone like me feels overwhelmed by all of the things that you have to grok in order to understand the language.
- throwaway7645 9y ago
  Think of it as incorporating many of the features in all of the languages you mentioned above, but in one language that is designed to grow. The language can easily be enhanced both officially and by the end user. So not too many new concepts for you, just a different syntax.
- lixquid 9y ago
  That's understandable; if you look at the slides and see all of the integrated features in one big blast, you're going to think "holy moly this was not meant for mortal men". In a way that's correct, because ultimately Perl6 is designed as the ultimate "kitchen sink" language; it has all the little features you could think of already baked in, which will include a lot of features you won't use. The main reason for this stems from the overarching design philosophy; "There is more than one way to do something". The language ultimately tries to be as flexible as possible, going so far as to support modification the the core grammar, the object system, etc. This is meant to make the developer as comfortable as possible, but it can lead the common case of perl-itis, also known as "write-once, read-nonce" code.
Thaxll 9y ago
Perl is pretty much dead, I don't anyone still using that beside legacy code.
- ue_ 9y ago
  Nobody's using P6 for legacy code.
  - Thaxll 9y ago
    What kind of sane person who would use Perl ( 6 or older ) on a new project nowdays.
    - ue_ 9y ago
      Me, albeit a small project, it was really fun to work on; it was an interactive blog.
    - nocman 9y ago
      Lots of "sane" people would (at least for Perl 5). I know it's not "the new hotness", but Perl 5 is still an incredibly useful language that a lot of people know (present company included). There are extensive libraries available for doing a lot of things that need to be done in day-to-day business. There are plenty of perfectly legitimate places to use it in new development. The Perl 5 porters development list has a decent amount of traffic ( http://www.nntp.perl.org/group/perl.perl5.porters/2017.html http://www.nntp.perl.org/group/perl.perl5.porters/2017.html ). And Perl 5 still has a good number of active contributors ( https://www.openhub.net/p/perl/contributors https://www.openhub.net/p/perl/contributors ). Also, The CPAN has plenty of modules with daily activity ( http://search.cpan.org/recent http://search.cpan.org/recent ). Even if you would not choose to do new development in Perl 5 (because of other language preferences, or whatever), that does not mean it is unreasonable (or "insane") for others to do so. Whether Perl 6 will ever catch on, I don't know. The language has a lot of features that look interesting, and I think it could also be very useful. I personally have not had time to look at it much yet, but probably will when I don't have higher priority things in life preventing me from doing so.
  - 9y ago
joosters 9y ago
Maybe it's because I'm old, but I don't see the appeal of M:N multiplexing in a programming language (i.e. 'green threads' or some other user-level context switching) For long-running tasks, if they are I/O bound you can use non-blocking I/O and event loops. If they are CPU bound, then use threads or separate processes. The two techniques can be combined to scale well across multiple cores. The OS is designed to schedule workloads, it has decades of development in doing this, and has all the system-wide information needed to schedule tasks well across the CPUs. why re-implement the wheel in your programming language?
- le-mark 9y ago
  > For long-running tasks, if they are I/O bound you can use non-blocking I/O and event loops. If they are CPU bound, then use threads or separate processes. The two techniques can be combined to scale well across multiple cores. One might suppose this to be the case, but to my knowledge only network IO is truly non blocking, although there are async io api's in some languages for disk reads/writes, they're still blocking behind the scenes. One of the coolest things about go (imo) is it's scheduling of many go routines onto relatively few machine threads (and processes) for blocking IO. I'm not clear if Perl 6 has such a facility.
  - j_s 9y ago
    I'm not an expert, but I think you're right for POSIX. Windows does apparently offer the necessary building blocks; this is the most relevant HN sub-discussion: https://news.ycombinator.com/item?id=9584269 https://news.ycombinator.com/item?id=9584269
    - deleted 9y ago
      [deleted]
    - lederhosen 9y ago
      aio - POSIX asynchronous I/O overview http://man7.org/linux/man-pages/man7/aio.7.html http://man7.org/linux/man-pages/man7/aio.7.html
athenot 9y ago
I'm glad Perl6 finally went the route of MoarVM. I always felt that ParrotVM (which was supposed to also run Python and Ruby) was a terrible distraction and scope creep. The idea was laudable but it would have required buy-in from the other communities. As much as I like Perl, I don't think that would have been fair to them, as Python and Ruby have evolved into their own respective identities.
- krylon 9y ago
  > The idea was laudable but it would have required buy-in from the other communities But imagine how cool it would have been - write a class in Python, sub-class it from Ruby, use that subclass in a function written in Perl, call that function from Lua code... Okay, I see it now. It was just too awesome for its time. Maybe in a hundred years or so...
  - bigleagueposter 9y ago
    JVM is now becoming what Parrot was intended to be with Graal/Truffle.
    - krylon 9y ago
      I guess so. But without Perl 5 and Perl 6 it is just not going to be the same. (Pouty face)
      - mst 9y ago
        Step 1. Fix Rakudo on the JVM Step 2. Fix the perl5-in-perl6 work Step 3. Retreat to a corner and sob until you recover some SAN points
  - deleted 9y ago
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mempko 9y ago
Best argument to use Perl 6 is that it's fun. Like really fun. Whatever language you are using is boring. Perl 6 is just damn fun. It's like your favorite language but with dollar signs, and funner.
- qbaqbaqba 9y ago
  Perl5 is also fun. Until you have to work with others' people code, or even your own older code.
  - raiph 9y ago
    Many P5 folk claim that it remains fun if the P5 code is well written. But regardless, having fun with P6, which is specifically designed to be readable, maintainable, composable, refactorable, etc. is fundamentally different from having fun with a language like P5.
nige123 9y ago
Perl 6 is indeed fun - it's even optimised for it [1]! I'm enjoying using it for command-line tools and web applications - it's expressive and scales with the problem space. 1. https://perl6advent.wordpress.com/2015/12/20/perl-6-christmas-have-an-appropriate-amount-of-fun/ https://perl6advent.wordpress.com/2015/12/20/perl-6-christma...
jonbarker 9y ago
Does this not help with handling this issue in python or is this considered a hack? http://effbot.org/zone/thread-synchronization.htm http://effbot.org/zone/thread-synchronization.htm
spion 9y ago
Needs a correction re: node.js. It does have await and does switch context now.
saysorry 9y ago
I ctrl+F searched these comments for the word "hipster", 0 matches. If this was about JavaScript though...
hardwaresofton 9y ago
It's pretty cool to see Perl adding this feature. My rubric for the three big scripting languages (once upon a time?) was: Perl: Good at regular expressions, and proper per-processor core threading, Bad because what you wrote will be indecipherable to future you Python: Very expressive (without being too much), lots of library support, good drop-to-c/do-stuff-fast support, sensible support for object and functional programming paradigms that evolved over time, super useful stdlib. Bad because GIL Ruby: ???? at least it's beautiful? seems to only be used in codebases that are rails-based which is basically a red flag for me now due to personal preference It looks like Perl just got another killer feature
- b2gills 9y ago
  Perl 5's base object system was based on Python's Ruby has been referred to as Perl 5 with a better object system. Perl 5 also has Moose an object system based on Perl 6's which has been ported to Python and to Ruby twice. The way to allow calling into C with NativeCall is almost seamless most of the time. It has also been used to make using modules/libraries from other languages even more seamless. (usually the only way you know the module is from a different language is the :from<Python> in the use directive.)
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16bytes 9y ago
Even though this could more properly be called, "Why having language support for M:N thread multiplexing is important", I thought it was a refreshing article on why I might actually use a bit of perl6. Last year I attended a conference and saw Larry Wall speak. It was an overview of Perl 6 and I was completely underwhelmed. Larry spent about half the time talking about unicode support. It wasn't a boring talk, but I never felt a moment when I said, "Awesome! This is a pain point in some other languages and I would pick up perl6 if this ever happened again." I don't want to write perl6 completely off, but I have found that perl6 advocates have not done a great job on why you would actually want to use it. It's hard to justify learning "different" syntax just because someone says, "hey, it's fun!".
- jxramos 9y ago
  I had saw an old coworker at a Python meetup group session the other week and I started to remember he and others had to support all these Perl scripts. Since leaving that place and seeing so much of Python everywhere I thought the other day where Perl wound up in the mix of things several years later. Seems like the community kept going.
- raiph 9y ago
  Extending Evan's analogy, perhaps trying to explain the joke ruins the joke?
- cutler 9y ago
  Better math is one good reason. Grammars are also a great feature of Perl 6.
  - 16bytes 9y ago
    I've never faced a problem in another modern language where math became a big problem. Even using something like numpy made never made me frustrated with, say, python's numerical types. From what I've seen perl6 makes some operations more convenient. Cool, I guess, but not a great reason to reach for perl6. Grammars are really cool, and one reason I might reach for perl6, but you also have really great special-purpose tools like Antlr. I suppose I don't feel the need grammars that often to need them reified in my language of choice, but next time I need to do some parsing, however, I will probably play around with perl6.
Paul_S 9y ago
This would've been so much easier if they just called Perl 6 something else. Would've saved them so much aggravation.
- daotoad 9y ago
  You aren't alone in thinking that. http://blogs.perl.org/users/zoffix_znet/2017/07/the-hot-new-language-named-rakudo.html http://blogs.perl.org/users/zoffix_znet/2017/07/the-hot-new-... https://github.com/perl6/marketing/blob/master/TablePosters/Rakudo-Concise/Rakudo-Concise--72ppi.png https://github.com/perl6/marketing/blob/master/TablePosters/...
kazinator 9y ago
All I think about when I hear M:N thread multiplexing is "1992 is calling to have its stupid threads hacks back". M:N is what you do when you don't have real kernel thread support. You hacked N user space threads per process (N:1) but then 1990 rolled in and cheap SMP with M processors started to spread across the land, so you needed N:M to take a bit of advantage of that.
- deleted 9y ago
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- b2gills 9y ago
  Perl 6 has M:N thread multiplexing along with normal thread support. It's just that M:N thread multiplexing is easier to use because all of the hard work is done for you.
cutler 9y ago
Perl 6 carries 2 pieces of baggage from its predecessor - prefixing variables with "my" to create lexical scope and the obligatory "use v6;" at the top of every script. Why can't an advanced language like Perl 6 scope variables without littering "my" everywhere? You don't see it in any other mainstream language I can think of.
- kbenson 9y ago
  > prefixing variables with "my" to create lexical scope Some people (such as me), prefer designating variable scope and easily identifying where a variable was defined. By the way, that isn't required by Perl 5. It was decided by the community that it was beneficial in that it solved far more problems debugging than the small bit of extra effort required, so the common refrain to "use strict;" was adopted because with that pragma it then is required. > Why can't an advanced language like Perl 6 scope variables without littering "my" everywhere? It could, but the community has decided it's not really beneficial. Have you actually examined why you think it's better? > obligatory "use v6;" at the top of every script That's not obligatory. You can omit at your leisure. If you do in include it and your script is accidentally called from a Perl 5 interpreter, you will either get an error, or if supported it will try to load a Perl 6 interpreter to parse the code.
- cygx 9y ago
  prefixing variables with "my" to create lexical scope I strongly disagree: From a languge design perspective, block-level lexical scoping with explicit declarations is superior to all alternatives I'm aware of.
- petre 9y ago
  How is this different than prefixing variables with var in JavaScript?
  - dugword 9y ago
    Just to be pedantic ;) var creates variables that are function scoped. my creates variables that are block scoped. let in JavaScript would be pretty much the same as my. Both are good things as they prevent typos from being new variables.

433 points by mpalme 9y ago

Read the article, very informative. Pleasantly surprised to find out that it doesn't mention at all language traits like syntax, but focuses on the features of Perl6's underlying VM, specifically MoarVM.

agumonkey 9y ago
Indeed, a GILless bytecode VM is worth a look.
- rurban 9y ago
  GIL less yes, but not lockless. The previous perl6 VM, parrot, had lockless threads, scaling linearly per native core. MoarVM even needs to lock on hash or array accesses, which is certainly not state of the art.
  - oconnor663 9y ago
    How did parrot write arrays from multiple threads without a lock somewhere in there?
    - bigleagueposter 9y ago
      The parrot threads didn't communicate with each other and you could wait until all of them finished. They provided a tiny subset of the functionality real threads offer but in a more efficient way.
    - rurban 9y ago
      You deferred updates to the owner via scheduler, with high prio, and continue. parrot threads are lock free but not wait free. The NQP compiler needed to know about threaded writes and schedule the update, with a semaphore, while the other threads continue. What MoarVM got better was everything else. The GC, the calling convention, the OO (6model), the jit. I was on my way to fix all the parrot damage done from the previous decade, because this would have enabled all architectures and proper threading for perl6, but then perl6 decided to kill it and go with Moar. And spread a lot of lies on threads.
      - pierrebai 9y ago
        I fail to see how using a semaphore to schedule work in another thread is "lock-free."
        rurban 9y ago
        Because you wait but you don't lock. And the wait is not 100x of an instruction, normally it's the same time as for one single instruction. Writes are fast and atomic, because there's no lock. Only the writer needs to wait a bit, not any other thread. Google for lock-free vs wait-free
petre 9y ago
Well, it should have mentioned Perl6 uses rational number math instead of floating point. I think this is a big advantage, since you can do more precise calculations using just the core language.

ricardobeat 9y ago

Crystal (http://crystal-lang.org http://crystal-lang.org) has fibers and channels. Current implementation isn't multi-threaded but it's being worked on. So you'll get that concurrency + nice syntax + types + a wonderful stdlib. EDIT: as seen in other responses, options abound: Python 3, Elixir, D, Dart and more all have built-in concurrency primitives, not to mention that discarding nodejs because of "callback hell" is at this point laughable.

giancarlostoro 9y ago
Not sure about channels but D has fibers. It is one reason / benefit of why vibe.d[0] was made. [0]: http://vibed.org/features http://vibed.org/features Note: Vibe.d is a web frameworks as well as a networking stack for D. If you're even remotely curious about D or do any web development I recommend you check out Vibe.d it is quite impressive (at the very least to me). Edit: There's apparently jin.go / Go.d: https://github.com/nin-jin/go.d https://github.com/nin-jin/go.d
holydude 9y ago
I am really,really excited about Crystal. I wish it success but I am afraid if the rails shops and big companies do not start using it it will be too little too late.
- goatlover 9y ago
  That would be unfortunate. I really like Crystal as a fast, typed alternative to Ruby, but I also prefer Ruby as a language to Go or even Elixir, which not everyone does.

_pmf_ 9y ago

> Concurrency is hard and if you want M:N thread multiplexing (i.e. WEB SCALE CODE, where application threads aren’t pinned to pthreads) your options today are precisely Erlang, Go, .NET, and Perl 6 Why mention .NET here? Async code in .NET works with a dispatcher thread (-pool) under the hood, which is nothing like the greenish threads that the other systems offer. Am I missing something?

pjmlp 9y ago
TPL, tasks are the greenish threads you mention. You can also just call Windows fibers directly, if feeling adventurous.
poooogles 9y ago
I mean core async in Clojure works the same, would you say it's the same? It might not be under the hood, but as perceived to the programmer it is?
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throwaway7645 9y ago

Perl6 is indeed a very nice language that I've been watching for a few years. As soon as the performance beats Python and the stability is solid I'll probably switch over from Python...there's just a lot there.

b2gills 9y ago
I have seen examples where the naive Perl 6 implementation is faster than the equivalent C code. (The one I'm thinking of is probably owing to Spesh and the JIT, but I forget what it was about) Here's an example where a naive Perl 6 version is going to beat the pants off of the naive version in another language: Find the sum of all integers from 10 to 1000000 inclusive. In Perl 6: say [+] 10 .. 1000000 the [+] is a left fold using the &infix:«+» operator (&infix:«+» is left associative) This finishes almost immediately. (It also does so if the endpoint is 10¹⁰⁰⁰ or more) The reason is if you use the built in version of the &infix:«+» operator, it calls the sum method on the Range object. That particular method knows how to calculate the sum on the Range without iterating through the values. If you modify the &infix:«+» operator lexically it won't take that shortcut. This also works the same if you wrote it like this: say Range.new(10,1000000).reduce(&[+]) (There is syntax to omit either or both endpoints with both ways to create a Range) There are plenty of areas where Rakudo Perl 6 is slower than I would like, but for many uses it is fast enough.
- slackersc 9y ago
  That's pretty cool! I started trying to learn perl6 and write my first interesting program. I have a copy of 'ray tracing in a weekend' and am trying to translate the basic ray tracer from c++ to perl6. It's remarkably slow right now.. It takes 1.5 minutes to generate an image. I tried to do the same thing in Julia and it takes 1.5 seconds. So I guess I must be doing something wrong!
  - raiph 9y ago
    Maybe it'd be fun to hack on https://github.com/raydiak/pray https://github.com/raydiak/pray?

IceDane 9y ago

> Why is this important? Concurrency is hard and if you want M:N thread multiplexing (i.e. WEB SCALE CODE, where application threads aren’t pinned to pthreads) your options today are precisely Erlang, Go, .NET, and Perl 6. I guess the author doesn't know about Haskell? The concurrency story for Haskell is great, and using the right library, you can literally just define types for the routes for your backend and then ask it to generate JS for your frontend.

aaron-lebo 9y ago
edit: dumb snark, but the replies are useful
- IceDane 9y ago
  No need for the snark. This isn't fanboyism, though I gladly admit that I'm fond of Haskell. I'm not just namedropping Haskell "just because". He claims those languages are the only one that have green threads. He's wrong. I corrected that.
  - aaron-lebo 9y ago
    You're right, that was overly snarky, but your post does come off as use Haskell -> magic. The concurrency stories for Erlang and Go are front and center, very well defined, and obvious. How do you get similar functionality in Haskell (specifically, what libraries do what you are talking about)?
    - IceDane 9y ago
      The library I was referring to is called servant[1]. It's a library for writing backends and clients in Haskell. I mentioned it because he said something about "webscale", but it doesn't have anything to do with concurrency. The go-to library for nice Haskell concurrency is probably async[2], which you can combine with stm[3] for very nice guarantees. If you're interested, there is a very nice, free book[4] on the subject. [1] https://haskell-servant.github.io/ https://haskell-servant.github.io/ [2] https://www.stackage.org/package/async https://www.stackage.org/package/async [3] https://www.stackage.org/package/stm https://www.stackage.org/package/stm [4] http://chimera.labs.oreilly.com/books/1230000000929/index.html http://chimera.labs.oreilly.com/books/1230000000929/index.ht...

SeanDav 9y ago

Without a "Major" sponsor, or a "Rails" type killer application, Perl 6, or indeed any language, will struggle to get significant traction. It is of course possible to gain slowly over time, but with numerous languages competing, that path may be a dead-end.

forinti 9y ago
Perl 6 still has to overcome Perl 5, which is everywhere and is a great language. I never get around to using Perl 6 because 5 is already there in every Linux distribution.
- bjd2385 9y ago
  I wish Linux distros shipped with more recent language versions, e.g. Python 3.6 and Perl 6 in addition to just 3.4/5 and 5. I understand that it's not their job to try and push people to update their language skills, but it'd be nice to have access to them right off the bat if they feel like it.
  - riffraff 9y ago
    python3.x vs 2.x is nowhere near the jump from perl5 to perl6. It's basically a different language that shares some things, with few users. It would be nice to see it shopped, but you might as likely wish distribution shipped with crystal or nim.
    - bjd2385 9y ago
      Hey, it was a wish lol. I know we live in the real world here
  - chriswarbo 9y ago
    The difference between Python minor versions (e.g. 3.4 to 3.6) is tiny compared to the difference between Perl 5 and 6. From what I've seen, the difference between Python 2.x and 3.x is tiny compared to the Perl 5/6 change.

mapcars 9y ago

It's terrible that you put Erlang on a list with other languges/VMs. >There’s no GIL, so unlike Those Other Languages There is no GIL in EVM as well, but playing with the words you make it look like "all are the same". This does not deserve top HN and just stupid. If your Perl6 VM is _so_ great, why didn't you mention anything about what's really important like preemptive scheduling which has been Erlang's unbeatable feature since the beginning? Less hype and more details, please.

macintux 9y ago
FWIW, the author is very well-known and respected in the Erlang world for his work on Chicago Boss. Any perceived slights against Erlang are likely unintentional.
b2gills 9y ago
The author of the article likely hasn't dug much into the VM code yet. https://github.com/MoarVM/MoarVM/#feature-overview https://github.com/MoarVM/MoarVM/#feature-overview

jypepin 9y ago

why is everybody saying they are put off by Go? Did we pass the "trend" phase and now it's cool to say go sucks?

kalekold 9y ago
lol no generics
notamy 9y ago
Tongue-in-cheek answer: lol no generics :) To be serious, in my circle of developer-friends, we feel that it tries to be TOO simple, and disagree with some of the decisions of how the language works (ex. seemingly endless `if err != nil { return nil, err }` type things)
- codegladiator 9y ago
  I always find it a bit funny when dev's try to put a label of "too simple" on a language. How would your friends label "brainfuck" ? Too simple because it has very limited number of identifiers or Too hard because accomplishing anything is nightmare ?
  - kazagistar 9y ago
    Simple is not the opposite of hard. The opposites are complex and easy.
FungalRaincloud 9y ago
I don't know about others, but I personally have always seen Go as an internal language for Google. This made me feel like it was appropriate for projects that I personally control, but unlikely to be useful in a career. That's really just a feeling, though, and I recognize that if everyone felt like I do, it would make Go a niche language that was actually probably pretty lucrative to know. So I wouldn't say I'm put off by it, so much as the balance of factors hasn't tipped in favor of learning it yet.
- 9y ago

rastapasta 9y ago

thanks for touching the heart of an old perlmonk :)

krylon 9y ago

Can anyone recommend a good book on Perl 6? Are there any (even bad ones)? Right now I feel the major reason that keeps me from investing time in Perl 6 - besides adoption by distros - is the lack of a good book, like the Lama and the Camel book for Perl 5. It's kind of frustrating after having waited so long.

totalperspectiv 9y ago
This one is 'in progress' https://www.learningperl6.com/ https://www.learningperl6.com/ Looking at the Perl 6 website, there are a few more coming along as well. https://perl6.org/resources/ https://perl6.org/resources/
- krylon 9y ago
  Nice, thank you very much!
- cutler 9y ago
  ... but nothing from Larry Wall. I don't get it. Perl 6 without a "Programming Perl 6" (O'Reilly or Pragmatic) will just delay adoption.
sigzero 9y ago
http://greenteapress.com/wp/think-perl-6/ http://greenteapress.com/wp/think-perl-6/
perlgeek 9y ago
https://perl6book.com/ https://perl6book.com/ gives an overview of Perl 6 books, and how they differ. Enjoy!
krylon 9y ago
To all who answered: Thank you very, very much!!!
_delirium 9y ago
> adoption by distros This has improved, and I think most distros now ship Rakudo (Perl6 on MoarVM). At least: Debian, Ubuntu, Fedora, and Arch do.

StevePerkins 9y ago

> Concurrency is hard and if you want M:N thread multiplexing (i.e. WEB SCALE CODE, where application threads aren’t pinned to pthreads) your options today are precisely Erlang, Go, .NET, and Perl 6. Putting aside the "web scale" jokes (http://www.mongodb-is-web-scale.com/ http://www.mongodb-is-web-scale.com/), this statement is still absurd. Every major language, or at least the ones that matter for backend development, has support for thread multiplexing / coroutines / fibers, whatever. Perhaps not in the core language syntax or standard library. But it's easy to implement with native code, and so SOMEONE has implemented it in a library if the language has an FFI. Java, and all of the other JVM-based languages in turn, have Quasar (http://docs.paralleluniverse.co/quasar/ http://docs.paralleluniverse.co/quasar/). Ruby has support for primitive fibers baked into the standard language (https://ruby-doc.org/core-2.1.1/Fiber.html https://ruby-doc.org/core-2.1.1/Fiber.html), and likewise community gems with more robust functionality like Quasar. Python 3 likewise has this out of the box (https://www.python.org/dev/peps/pep-0492/ https://www.python.org/dev/peps/pep-0492/). The list goes on and on: https://en.wikipedia.org/wiki/Coroutine#Programming_languages_with_native_support https://en.wikipedia.org/wiki/Coroutine#Programming_language....

rootlocus 9y ago
I'd like to know why people are downvoting this.
- dragonwriter 9y ago
  Probably because it treats a high-level feature (M:N threading) as equivalent to a lower-level feature (coroutines) and then compounds that by treating as equivalent languages where the former is built into the core with ones where the latter is available as a third-party library, all as a way of dismissing the value of languages where the former feature is built in to the core, and layered with scorn and derision on top of being doubly wrong. Now, I preferred correction to downvoting, but I can easily see why others would choose downvoting.
- thehardsphere 9y ago
  People often downvote anything that's remotely negative, even if it is true or merely a critical question.

fundabulousrIII 9y ago

I'll stick with Tcl if I'm going to use a glue language that has green thread like functionality and an event loop. early choices were tcl or perl: went Tcl and never looked back. As far as web development in perl..well have fun convincing everyone on the node.js and python bandwagons to move 'back' to perl. Glad it works for you.

totalperspectiv 9y ago
I hadn't heard of Tcl before but it looks awesome! What do you find its ideal use cases to be?
- forinti 9y ago
  I use Tcl/Tk from time to time and it always seems the easy choice when I need a simple GUI and also need to make an executable for Windows (which is trivial with Freewrap). Some of the things I've written are: a simple standby order input app, a Forms/Reports compiler (sends file to server, waits for response and informs user), and a Ghostscript wrapper for merging lots of PDFs into one file.
  - totalperspectiv 9y ago
    Awesome! I'm definitely going to be keeping it in mind as little projects come up that could use a GUI.
- williadc 9y ago
  TCL is really great for throwing syntax errors at runtime, having no real data structures, and an inconsistent API!
  - logicchains 9y ago
    Better than throwing syntax errors at compile time; saves the programmer time. By the time errors happen, it's the customer's problem instead.
- 9y ago

ainar-g 9y ago

Can Perl6 merge all of its generated VM code into one "package"? One of my favourite things about Go is that you can statically compile everything and then deployment basically becomes scp.

rlpb 9y ago
...and then deployment basically becomes scp. And security updates for your deployment become...what?
- sherr 9y ago
  Rebuild and scp the whole lot again? Not necessarily a big deal.
  - rlpb 9y ago
    Rebuilding by pulling in all your dependencies from the Internet again? That's not something I want to do when the clock is ticking to get a security update out. What if some random third party dependency is hosted somewhere that is down, or has been pulled? And how do I know I have to rebuild in the first place? You'll probably tell me that there are tools to help deal with this. I'm sure there are. My point is that it isn't as simple as "scp".
  - xutopia 9y ago
    Or doing patches. Copy the file locally... apply the patch... restart process.
hpcjoe 9y ago
I find it somewhat humorous that more than 25 years on, we are effectively reverting to static linking and bundling [1]. Way ... way back in the day, the argument was it would save memory, encourage reuse, etc. While some of this may have been true, it also gave rise to dynamic library hell. Reuse was overshadowed by incompatible versions, or API changes between versions that became the stuff of legends. This would make a great study in how the ROI was completely overshadowed by risk considerations not considered at the outset. Of course, saving memory was a huge issue in the days when 1GB RAM was considered gigantic. So maybe the cost was worth it. [1] https://scalability.org/2017/03/what-is-old-is-new-again/ https://scalability.org/2017/03/what-is-old-is-new-again/

pmontra 9y ago

On a sidenote > or Nginx or Node.js without the callback cacciatore. What's a cacciatore in this context? It means hunter in Italian. Probably something messy if it means the same as callback hell.

credit_guy 9y ago
I read it as a short version of chicken cacciatore, which is a dish with an appearance that may look messy.
- Sean1708 9y ago
  That makes sense I suppose, it's a cacciatore made with callbacks instead of chicken.
dagw 9y ago
cacciatore is a style of rustic stew in Italian cooking.
- riffraff 9y ago
  "alla cacciatora" is the name of the style in Italian, that somehow got mangled in english. Kinda like "gabagool" which is effectively an american only name for an italian product we call "capocollo". pmontra is italian, hence the confusion.
- pmontra 9y ago
  I would have bet that cacciatore was about food. To be pedantic, that's "alla cacciatora" but I won't be picky with Italian food terms outside Italy, it's good advertising anyway (I'm an Italian in Italy.)
  - orbitur 9y ago
    > To be pedantic, that's "alla cacciatora" but I won't be picky with Italian food terms outside Italy It's good that you won't be picky, since you're arguing against decades of "cacciatore" for Italian Americans. ;)

Rjevski 9y ago

My personal issue with Perl is how much of a mess the syntax is (10 different ways of doing the same thing), and the lack of a standard library (CPAN is not a viable replacement).

IslaDeEncanta 9y ago
Why is CPAN not a viable replacement? It has always been perfectly viable for me.
- Rjevski 9y ago
  CPAN packages are written by thousands of different people with varying styles (cf. the issue with 10 different ways of doing the same thing), quality standards and maintenance schedules. In Python I can expect the standard library to be consistent and be maintained as part of the core language. Now I don't mean that everything has to be in the standard library (I'm fine with the database access libraries being third-party for example), but in Perl even the most basic stuff like exceptions is only on CPAN and there are again multiple packages to choose from..
  - b2gills 9y ago
    Unfortunately for Python is that many/most of the modules that are included were written when the language was fairly new, so at a time when nobody was an expert in the language. Which means that perhaps for many of them there is a better module out in the ecosystem that almost nobody uses because they have one extra step to install them. If you want something close to that in Perl 6, just install Inline::Python and you can use all of those “batteries included” with Python as if they were modules written in Perl 6. Exceptions in Perl 6 are much easier to deal with than they are in Perl 5.
yellowapple 9y ago
I'll take 10 different ways to do the same thing with different approaches over one "true" way with no flexibility any day. Perl gives the programmer a lot of rope to work with. Whether one ties that rope into a drawbridge or a noose is the programmer's choice. Also, CPAN is fantastic and widely supported. I really wish more languages would follow its example, especially when it comes to package namespaces.

grondilu 9y ago

> Guess what it outputs? Nothing! Just kidding, you’ll see a lot of distressed messages from tasks that passed out wait for the phone to ring, and woke up wearing someone else’s OS thread. Well, as a matter of fact I really got no output at all :(

libeclipse 9y ago
> Actually, the program will output nothing if you’re using a release of Perl 6 prior to Rakudo Star 2017.07; a caching bug previously caused $*THREAD.id to report an out-of-date value.

pvdebbe 9y ago

I like writing bash scripts a lot and perl is a natural step-up with powerful libraries to use. As others have said, the major obstacle for me has been the lack of great literature.

yellowapple 9y ago
There's lots of literature out there for Perl 5 (like the so-called "Camel Book"). Perl 6 literature is pretty scarce, though.
- throwaway7645 9y ago
  There is 2 out now and many in development. So really not that bad.
  - cygx 9y ago
    2? It's 5 now! https://www.apress.com/us/book/9781484228982 https://www.apress.com/us/book/9781484228982 http://shop.oreilly.com/product/0636920065883.do http://shop.oreilly.com/product/0636920065883.do https://deeptext.media/perl6-at-a-glance/ https://deeptext.media/perl6-at-a-glance/ https://deeptext.media/migrating-to-perl6 https://deeptext.media/migrating-to-perl6 https://www.amazon.com/Learning-program-Perl-Getting-programming-ebook/dp/B07221XCVL https://www.amazon.com/Learning-program-Perl-Getting-program...
    - throwaway7645 9y ago
      No idea the other ones came out so fast :)
dmytrish 9y ago
For small tasks I enjoy aesthetics of small dedicated Unix tools (grep, sed, awk, cut, sort) working together much more. Perl tries to be everything at once, still mysteriously lacking interactive REPL out of the box. Yes, Python is more heavyweight for scripting, but it pays in the long term with better maintenance and tooling for big scripts.

libeclipse 9y ago

Thing that really gets me about perl is the syntax, it's horrendous. No other reason, that's all. Just the syntax.

tankenmate 9y ago
Blame Aho, Weinberger, and Kernighan. Oh and Larry :)
- tannhaeuser 9y ago
  Why are the awk guys to blame for Perl syntax?
  - tankenmate 9y ago
    > (It's sorta like sed, but not. It's sorta like awk, but not. etc.) Guilty as charged. Perl is happily ugly, and happily derivative. Usenet article <1992Aug26.184221.29627@netlabs.com> (1992) -- Larry Wall
    - vgy7ujm 9y ago
      I don't see the problem here... those are good tools and Perl have those tools power in the core language++ Good stuff if you ask me.
- fnord123 9y ago
  The good thing about awk is that it's limited. So you know when to stop using it and move to use a different language when your requirements exceed the comfort zone of awk. Larry Wall came and made a language inspired by awk that doesn't give feedback on when you're out of the comfort zone. This lets you make a mess before you know what you've done (aka technical debt). The same problem 'that killed Smalltalk and could have killed ruby' too (thanks, Bob Martin).
Scarblac 9y ago
It's _different_. But working for a few years with Perl 5, it really grew on me. It could use a good "Perl: The Good Parts" book, I guess. I haven't looked at Perl 6 yet, don't know if that's better or worse. Too many other things to do, and I don't think I'll ever work with Perl professionally again, that ship has probably sailed.

contingencies 9y ago

Great quote on perl5... In #devops is turtle all way down but at bottom is perl script. - @devopsborat

tripa 9y ago
I like how the original was agnostic, yet you interpreted as perl5 :-)
- contingencies 9y ago
  I think it's common knowledge that perl6 is basically rare in deployment, whereas perl5 scripts are everywhere in legacy systems. Former CPAN author myself.

Steeeve 9y ago

I hate perl6. I hate it because I tried to get involved in the project early on, and it led me down the Haskell rathole. I don't know what Haskell looks like today, but a decade or more ago it was the hardest language to pick up that I had ever experienced. It was as if I had a solid background in latin languages and I was trying to pick up Chinese based on a handful of tutorials written by a tourist on the back of a napkin. But it has been a decade and I am truly impressed with what it has turned into. Unfortunately, it has to re-gain mindshare as if it was starting from scratch. It might be a little bit harder actually, because there are a variety of scripting languages these days that are easy to learn, and there are still more than a few people who actively don't like Perl. I really liked this slideshow: http://tpm2016.zoffix.com/#/ http://tpm2016.zoffix.com/#/ It gives a good review of Perl6 from early 2016. The video is an hour and a half, but it only takes a few minutes to scan through the slides and find the interesting pieces. (left and right arrow to navigate the slides)

txdv 9y ago
I looked quickly through the slides and saw that perl has now grammar build in the language... Truly an interesting feature
- perlgeek 9y ago
  It is. You can build recursive descending parsers with a declarative syntax, and all the benefits from having it in OO (role composition, inheritance). Here is a working grammar for INI config files: https://github.com/tadzik/perl6-Config-INI/blob/master/lib/Config/INI.pm#L5 https://github.com/tadzik/perl6-Config-INI/blob/master/lib/C...
- dmytrish 9y ago
  Is the language itself a good place for parsing/grammar handling? I could not even find in the standard documentation which kind of parsers it supports, is it LR(k)? LL(k)? Any CFG? What parsing method does it use: recursive descent, shift-reduce, something more general like CYK/Earley algorithms? How does it handle ambiguities? It turns out that `grammar` keyword generates recursive descent parsers and anything even a bit fancier still requires a dedicated parsing library.

Verdex_2 9y ago

For some reason, when I started my software engineering career I got it into my head that I needed to learn as much as I could about programming languages. I learned ruby, perl5, python, lisp, forth, ml, ocaml, scheme, haskell, r, c#, java, lua, c++, factor, idris, asm, erlang, prolog, rust, d. But that wasn't quite enough because haskell and idris kept on talking about complicated type theory stuff. So I also learned lambda calculus, type theory, set theory, domain theory, topology, category theory, information theory, sub-structural logic. What I'm trying to say is that I'm not afraid of learning new things. Even if they seem hard or esoteric. When I heard that perl6 was ready, I took a look. I like the idea of a lot of what is present in the language (hey look, a grammar engine, that's neat). But ultimately, I decided that it was too much stuff that I would have to learn. Maybe that's just a perception problem on my part, but I have to think that they have some sort of problem if someone like me feels overwhelmed by all of the things that you have to grok in order to understand the language.

throwaway7645 9y ago
Think of it as incorporating many of the features in all of the languages you mentioned above, but in one language that is designed to grow. The language can easily be enhanced both officially and by the end user. So not too many new concepts for you, just a different syntax.
lixquid 9y ago
That's understandable; if you look at the slides and see all of the integrated features in one big blast, you're going to think "holy moly this was not meant for mortal men". In a way that's correct, because ultimately Perl6 is designed as the ultimate "kitchen sink" language; it has all the little features you could think of already baked in, which will include a lot of features you won't use. The main reason for this stems from the overarching design philosophy; "There is more than one way to do something". The language ultimately tries to be as flexible as possible, going so far as to support modification the the core grammar, the object system, etc. This is meant to make the developer as comfortable as possible, but it can lead the common case of perl-itis, also known as "write-once, read-nonce" code.

Thaxll 9y ago

Perl is pretty much dead, I don't anyone still using that beside legacy code.

ue_ 9y ago
Nobody's using P6 for legacy code.
- Thaxll 9y ago
  What kind of sane person who would use Perl ( 6 or older ) on a new project nowdays.
  - ue_ 9y ago
    Me, albeit a small project, it was really fun to work on; it was an interactive blog.
  - nocman 9y ago
    Lots of "sane" people would (at least for Perl 5). I know it's not "the new hotness", but Perl 5 is still an incredibly useful language that a lot of people know (present company included). There are extensive libraries available for doing a lot of things that need to be done in day-to-day business. There are plenty of perfectly legitimate places to use it in new development. The Perl 5 porters development list has a decent amount of traffic ( http://www.nntp.perl.org/group/perl.perl5.porters/2017.html http://www.nntp.perl.org/group/perl.perl5.porters/2017.html ). And Perl 5 still has a good number of active contributors ( https://www.openhub.net/p/perl/contributors https://www.openhub.net/p/perl/contributors ). Also, The CPAN has plenty of modules with daily activity ( http://search.cpan.org/recent http://search.cpan.org/recent ). Even if you would not choose to do new development in Perl 5 (because of other language preferences, or whatever), that does not mean it is unreasonable (or "insane") for others to do so. Whether Perl 6 will ever catch on, I don't know. The language has a lot of features that look interesting, and I think it could also be very useful. I personally have not had time to look at it much yet, but probably will when I don't have higher priority things in life preventing me from doing so.
- 9y ago

joosters 9y ago

Maybe it's because I'm old, but I don't see the appeal of M:N multiplexing in a programming language (i.e. 'green threads' or some other user-level context switching) For long-running tasks, if they are I/O bound you can use non-blocking I/O and event loops. If they are CPU bound, then use threads or separate processes. The two techniques can be combined to scale well across multiple cores. The OS is designed to schedule workloads, it has decades of development in doing this, and has all the system-wide information needed to schedule tasks well across the CPUs. why re-implement the wheel in your programming language?

le-mark 9y ago
> For long-running tasks, if they are I/O bound you can use non-blocking I/O and event loops. If they are CPU bound, then use threads or separate processes. The two techniques can be combined to scale well across multiple cores. One might suppose this to be the case, but to my knowledge only network IO is truly non blocking, although there are async io api's in some languages for disk reads/writes, they're still blocking behind the scenes. One of the coolest things about go (imo) is it's scheduling of many go routines onto relatively few machine threads (and processes) for blocking IO. I'm not clear if Perl 6 has such a facility.
- j_s 9y ago
  I'm not an expert, but I think you're right for POSIX. Windows does apparently offer the necessary building blocks; this is the most relevant HN sub-discussion: https://news.ycombinator.com/item?id=9584269 https://news.ycombinator.com/item?id=9584269
  - deleted 9y ago
    [deleted]
  - lederhosen 9y ago
    aio - POSIX asynchronous I/O overview http://man7.org/linux/man-pages/man7/aio.7.html http://man7.org/linux/man-pages/man7/aio.7.html

athenot 9y ago

I'm glad Perl6 finally went the route of MoarVM. I always felt that ParrotVM (which was supposed to also run Python and Ruby) was a terrible distraction and scope creep. The idea was laudable but it would have required buy-in from the other communities. As much as I like Perl, I don't think that would have been fair to them, as Python and Ruby have evolved into their own respective identities.

krylon 9y ago
> The idea was laudable but it would have required buy-in from the other communities But imagine how cool it would have been - write a class in Python, sub-class it from Ruby, use that subclass in a function written in Perl, call that function from Lua code... Okay, I see it now. It was just too awesome for its time. Maybe in a hundred years or so...
- bigleagueposter 9y ago
  JVM is now becoming what Parrot was intended to be with Graal/Truffle.
  - krylon 9y ago
    I guess so. But without Perl 5 and Perl 6 it is just not going to be the same. (Pouty face)
    - mst 9y ago
      Step 1. Fix Rakudo on the JVM Step 2. Fix the perl5-in-perl6 work Step 3. Retreat to a corner and sob until you recover some SAN points
- deleted 9y ago
  [deleted]

mempko 9y ago

Best argument to use Perl 6 is that it's fun. Like really fun. Whatever language you are using is boring. Perl 6 is just damn fun. It's like your favorite language but with dollar signs, and funner.

qbaqbaqba 9y ago
Perl5 is also fun. Until you have to work with others' people code, or even your own older code.
- raiph 9y ago
  Many P5 folk claim that it remains fun if the P5 code is well written. But regardless, having fun with P6, which is specifically designed to be readable, maintainable, composable, refactorable, etc. is fundamentally different from having fun with a language like P5.

nige123 9y ago

Perl 6 is indeed fun - it's even optimised for it [1]! I'm enjoying using it for command-line tools and web applications - it's expressive and scales with the problem space. 1. https://perl6advent.wordpress.com/2015/12/20/perl-6-christmas-have-an-appropriate-amount-of-fun/ https://perl6advent.wordpress.com/2015/12/20/perl-6-christma...

jonbarker 9y ago

Does this not help with handling this issue in python or is this considered a hack? http://effbot.org/zone/thread-synchronization.htm http://effbot.org/zone/thread-synchronization.htm

spion 9y ago

Needs a correction re: node.js. It does have await and does switch context now.

saysorry 9y ago

I ctrl+F searched these comments for the word "hipster", 0 matches. If this was about JavaScript though...

hardwaresofton 9y ago

It's pretty cool to see Perl adding this feature. My rubric for the three big scripting languages (once upon a time?) was: Perl: Good at regular expressions, and proper per-processor core threading, Bad because what you wrote will be indecipherable to future you Python: Very expressive (without being too much), lots of library support, good drop-to-c/do-stuff-fast support, sensible support for object and functional programming paradigms that evolved over time, super useful stdlib. Bad because GIL Ruby: ???? at least it's beautiful? seems to only be used in codebases that are rails-based which is basically a red flag for me now due to personal preference It looks like Perl just got another killer feature

b2gills 9y ago
Perl 5's base object system was based on Python's Ruby has been referred to as Perl 5 with a better object system. Perl 5 also has Moose an object system based on Perl 6's which has been ported to Python and to Ruby twice. The way to allow calling into C with NativeCall is almost seamless most of the time. It has also been used to make using modules/libraries from other languages even more seamless. (usually the only way you know the module is from a different language is the :from<Python> in the use directive.)

deleted 9y ago

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16bytes 9y ago

Even though this could more properly be called, "Why having language support for M:N thread multiplexing is important", I thought it was a refreshing article on why I might actually use a bit of perl6. Last year I attended a conference and saw Larry Wall speak. It was an overview of Perl 6 and I was completely underwhelmed. Larry spent about half the time talking about unicode support. It wasn't a boring talk, but I never felt a moment when I said, "Awesome! This is a pain point in some other languages and I would pick up perl6 if this ever happened again." I don't want to write perl6 completely off, but I have found that perl6 advocates have not done a great job on why you would actually want to use it. It's hard to justify learning "different" syntax just because someone says, "hey, it's fun!".

jxramos 9y ago
I had saw an old coworker at a Python meetup group session the other week and I started to remember he and others had to support all these Perl scripts. Since leaving that place and seeing so much of Python everywhere I thought the other day where Perl wound up in the mix of things several years later. Seems like the community kept going.
raiph 9y ago
Extending Evan's analogy, perhaps trying to explain the joke ruins the joke?
cutler 9y ago
Better math is one good reason. Grammars are also a great feature of Perl 6.
- 16bytes 9y ago
  I've never faced a problem in another modern language where math became a big problem. Even using something like numpy made never made me frustrated with, say, python's numerical types. From what I've seen perl6 makes some operations more convenient. Cool, I guess, but not a great reason to reach for perl6. Grammars are really cool, and one reason I might reach for perl6, but you also have really great special-purpose tools like Antlr. I suppose I don't feel the need grammars that often to need them reified in my language of choice, but next time I need to do some parsing, however, I will probably play around with perl6.

Paul_S 9y ago

This would've been so much easier if they just called Perl 6 something else. Would've saved them so much aggravation.

daotoad 9y ago
You aren't alone in thinking that. http://blogs.perl.org/users/zoffix_znet/2017/07/the-hot-new-language-named-rakudo.html http://blogs.perl.org/users/zoffix_znet/2017/07/the-hot-new-... https://github.com/perl6/marketing/blob/master/TablePosters/Rakudo-Concise/Rakudo-Concise--72ppi.png https://github.com/perl6/marketing/blob/master/TablePosters/...

kazinator 9y ago

All I think about when I hear M:N thread multiplexing is "1992 is calling to have its stupid threads hacks back". M:N is what you do when you don't have real kernel thread support. You hacked N user space threads per process (N:1) but then 1990 rolled in and cheap SMP with M processors started to spread across the land, so you needed N:M to take a bit of advantage of that.

deleted 9y ago
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b2gills 9y ago
Perl 6 has M:N thread multiplexing along with normal thread support. It's just that M:N thread multiplexing is easier to use because all of the hard work is done for you.

cutler 9y ago

Perl 6 carries 2 pieces of baggage from its predecessor - prefixing variables with "my" to create lexical scope and the obligatory "use v6;" at the top of every script. Why can't an advanced language like Perl 6 scope variables without littering "my" everywhere? You don't see it in any other mainstream language I can think of.

kbenson 9y ago
> prefixing variables with "my" to create lexical scope Some people (such as me), prefer designating variable scope and easily identifying where a variable was defined. By the way, that isn't required by Perl 5. It was decided by the community that it was beneficial in that it solved far more problems debugging than the small bit of extra effort required, so the common refrain to "use strict;" was adopted because with that pragma it then is required. > Why can't an advanced language like Perl 6 scope variables without littering "my" everywhere? It could, but the community has decided it's not really beneficial. Have you actually examined why you think it's better? > obligatory "use v6;" at the top of every script That's not obligatory. You can omit at your leisure. If you do in include it and your script is accidentally called from a Perl 5 interpreter, you will either get an error, or if supported it will try to load a Perl 6 interpreter to parse the code.
cygx 9y ago
prefixing variables with "my" to create lexical scope I strongly disagree: From a languge design perspective, block-level lexical scoping with explicit declarations is superior to all alternatives I'm aware of.
petre 9y ago
How is this different than prefixing variables with var in JavaScript?
- dugword 9y ago
  Just to be pedantic ;) var creates variables that are function scoped. my creates variables that are block scoped. let in JavaScript would be pretty much the same as my. Both are good things as they prevent typos from being new variables.