aartist has asked for the wisdom of the Perl Monks concerning the following question:

Do you use Perl 6 or Perl 5 ? What are the test-cases when a user or group or organization moves adopts Perl 6 ? Thanks.

Replies are listed 'Best First'.
Re: Reasons for Using Perl 6
by stevieb (Abbot) on Dec 22, 2017 at 16:37 UTC

    It's not really a "move to" thing. perl6 is a completely different programming language. It's not an updated perl5 in any stretch of the imagination. They are as different as perl5 vs Python for example.

    Personally, I use perl5, but I do dabble a bit periodically with perl6; not enough however to have produced any releases of anything though.

      Hi stevieb,

      while I agree with most of your post (++), I think that this sentence:

      They are as different as perl5 vs Python for example.
      isn't true (or, at the very least, is a gross exaggeration). Yes Perl 5 and Perl 6 are different programming languages, but they share the same philosophy and a lot of the syntax, so they are much closer to each other than any of these two is from Python.

      Despite their differences, learning Perl 6 with a Perl 5 background is very easy, while learning, say, Perl 5 with a Python background takes much more effort and even, in a way, a mental paradigm shift. I can claim that I really know what I am talking about here, since I have gone through these two processes: I was using Python (many years ago) before I took up Perl 5, and, of course, more recently I learned Perl 6.

      Once I learned Perl 5, I essentially gave up coding in Python (except for some legacy code and for a few experiments with Python's new constructs), but the fact that I've learned Perl 6 doesn't mean that I have stopped using Perl 5 in any way, I'm still using Perl 5 more than Perl 6 (notably at $work).

        They share a lot of the syntax except for the cases where the committee decided to make useless incompatible and confusing changes.

        Enoch was right!
        Enjoy the last years of Rome.

Re: Reasons for Using Perl 6
by holli (Monsignor) on Dec 22, 2017 at 20:32 UTC
    • Math that works
    • spot-on (unlike Perls "bolted-on") OO system
    • built-in asynchronicity/concurrency
    • outstanding Unicode support
    Just to name few.


    You can lead your users to water, but alas, you cannot drown them.
      Yes, holli, by all means. I would add grammars.
      • "Math that works" is what? An attempt to circumvent the restrictions of the computer computational model at the expense of making actual computation insanely slow? I guess that might mean it works, but is it useful? Or do you mean something else?
      • And that's a good thing why?
      • Which was one of the reasons the implementation took almost twenty years already and the result is still prohibitively slow.
      • mkay

      Enoch was right!
      Enjoy the last years of Rome.

        Floating-point arithmetic is flawed and sucks, and has sucked for probably 40+ years by now (which is really a very long period when speaking about modern technologies). It is actually outrageous that this hasn't been fixed over such a long period. Experienced programmers know it and have been accustomed to live with that. Does that mean that we should accept this flaw? I don't think so. IMHO, we should get rid of that flaw, we need a flexit.

        Consider this in Python:

        >>> .3 - .2 - .1 -2.7755575615628914e-17
        The result is very small, but it should really be 0.

        It's not better in Perl 5:

        $ perl -E 'say .3 - .2 - .1;' -2.77555756156289e-17
        Of course, neither Python nor Perl 5 is responsible for that, it is the FP arithmetic of the underlying architecture which sucks.

        Does this mean we can't do anything about it? Yes, we can, Perl 6 has this right:

        > say .3 - .2 - .1; 0 > printf "%.50f\n", .3 - .2 - .1; 0.00000000000000000000000000000000000000000000000000
        Getting an accurate result for such a simple calculation is not anecdotal. It is a real and major improvement. You can compare non integers for equality and get the correct result. Don't do that with most other programming languages.

        Yes, this improvement comes with a cost. So long as we have hardware that is inaccurate, we'll need to work around it with software, and this is bound to be somewhat slower. Personally, I think that accuracy is more important than speed.

        If speed was the only criteria, none of us would use Perl, we would all write our programs in C, nay, probably in assembly. But we don't. So, most of the time, speed is not the most important factor for us.

        Well, sometimes, speed matters. And I probably would not argue for accuracy if that meant that computation was really "insanely slow," as you claim. But it is not insanely slow; it is just somewhat slower, as shown in my earlier post above, and this speed issue could just be solved with a faster CPU. And, as I said earlier, there are performance enhancements almost every week (and some very big ones should be there very soon).

        Without wanting to really move you from your strong opinions strongly held about Perl 6, is perf -especially numeric- actually prohibitively slow still? Have you done any numeric work in Perl 6 in say the last six months to a year? I'd gently suggest it's really not that bad anymore. Rational maths is always going to be slower than floating point due to hardware support. Comparing like for like though Im not sure the difference is so big its something that would stop me. At least if I was using something as slow as Perl 5 for numeric work to begin with perf is clearly not what I cared about! For the P6 advent this year I did a bit of a write up on my personal long wait for perf, its really not what it once was
Re: Reasons for Using "Perl6" (don't need to earn a living?)
by 1nickt (Monsignor) on Dec 22, 2017 at 17:30 UTC

    As far as I know, there are no groups or organizations that have adopted "Perl6" other than hobbyist clubs. It is not a production-ready language, still breaks backwards compatibility with new releases, has a dearth of library extensions for doing real work, and is orders of magnitude slower than using Perl for the things it can do. It's an interesting project that has attracted some very bright minds over the 20 years or so it's been talked about, but it really doesn't have much to do with Perl other than its unfortunate cooption of the name.

    99.99% or so of the discussion in this Monastery is about Perl 5, because that's the actual practical programming language that we mostly all use and love.

    The way forward always starts with a minimal test.
      As far as I know, there are no groups or organizations that have adopted "Perl6" other than hobbyist clubs.
      I guess that's probably correct, although the term "hobbyist clubs" seems a bit deragotary here.
      It is not a production-ready language ...
      Pure prejudiced opinion, at variance with facts
      ... still breaks backwards compatibility with new releases,
      I do not know such case (except for very minor fixes or adaptation to new Unicode standards), perhaps you can enlighten us.
      ... has a dearth of library extensions for doing real work
      Well I agree that the P6 ecosystem is not as rich and as mature as the P5 CPAN, but there are many hundreds of modules for almost everything useful. See And you can use most P5 modules in Perl 6, as well as Python, C and Java libraries (much more easily than it would be in P5).
      ... and is orders of magnitude slower than using Perl for the things it can do...
      You should update your information, that may have been true 3 or 4 years ago, but that's no longer true. P6 might still be slightly slower than P5 for quite a few things (and may be faster for others), but it's certainly not "orders of magnitude" behind in terms of speed.
      but it really doesn't have much to do with Perl
      Not true. These two languages are different programming languages, but they are very close to each other, like brothers and sisters.

      On the issue of the similar names, well, yes, perhaps, it may be unfortunate, things evolved in an unpredicted way. I am afraid it will probably be difficult to change it now.

      To the OP: for the sake of full disclosure, I am the author of one of the Perl 6 books, so I may have my own prejudices. But 1nickt has been known here as a regular staunch opponent to P6, and may have his own. But I guess you discovered by yourself that we disagree on that.

      Update: fixed a couple of minor typos.

        Could you say more about the facts of it being production-ready?

        You acknowledged the ecosystem issue. But isn't that a major part of production-readiness? I just had a look around, but it seems not quite CPAN like e.g clicking on any of the modules there takes you to various github pages, so the documentation and other benefits of CPAN aren't there. Is there a plan for it to be more like CPAN?

        If it were production-ready, some team would adopt it for production work. If you consider "there are no groups or organizations that have adopted "Perl6" other than hobbyist clubs" probably correct then you'd probably agree it's not seen as production-ready. Or even close enough to production-ready to start a longer project in hope it's going to get production-ready in time for the project to go to production.

        I've seen several "all behold, I've made Perl 6 quicker" posts here on Perlmonks and while the message to stand in awe of claimed to have made Perl6 several times quicker, it was still at least two magnitudes slower than a matching Perl 5 solution.

        Those two languages are different programming languages, but I would not consider them just siblings. They are more like a person and his atomic-waste-mutated brother with several extra limbs at weird places, odd number of eyes and many extra organs that nobody knows the purpose of.

        Enoch was right!
        Enjoy the last years of Rome.

        Hi esteemed Brother Laurent_R, I don't care to get into a point by point debate with you. I will say only that I base my statements on what I have read with my own eyes in the last 6 - 8 months.

        • Tux announces 10% speed boost in P6 CSV handling, bringing P6 to less than 350 times slower than Perl: August 2017
        • "Zoffix", TPF-funded P6 developer and cheerleader, states: "Tiny ecosystem full of abandoned modules; Slow; Buggy ;Some stuff still gets changed around, so you may need to tweak your code to work on latest-and-greatest version once in a while; No mature modules for common tasks; your options are to roll your own, use works in progress, or use Perl 5's modules via Inline::Perl5 and pray it works." on Reddit, May 2017
        • Official notice of breaking changes on "Perl6" website, April 2017
        • has had a design change since the summer so I can no longer find the quote but until recently P6 was described there as not production-ready. I've noted it in various posts on the topic. The language on sites now emphasizes that Perl and P6 are not compatible.

        As I have stated before, I am not an opponent to "Perl6" - my problem is with the hijacking of the name, versioning number, reputation, community and funding of Perl to promote a new experiment. As long as the P6 proponents use that confusion to promote their agenda, I'll continue clarifying to promote mine: the health and longevity of Perl.

        The way forward always starts with a minimal test.
Re: Reasons for Using Perl 6
by sundialsvc4 (Abbot) on Dec 22, 2017 at 20:05 UTC

    I will herewith endure the usual expected firestorm of down-votes to express the personal opinion that “Perl-6” would have much-better been introduced to the world under any one of the various project code-names by which it was previously known during the many(!) years in which various competing(!!) implementation teams fought over it.   Because, when the dust finally settled, the thing that they had actually come up with was “an entirely new language,” not any sort of “readily forward-compatible successor to” the language that had come before.   Furthermore, it had a technically-confusing implementation stance:   suddenly it had become a thing that was to be “implemented upon” a variety of different technical foundations – none of which it apparently could actually call its own.

    (Quite a departure from the “iddy-biddy executable that ran like a bat out of hell” that we once knew and loved ... and that we still know today!)

    And, if I may further extend my helmet (at this point, why not?) above the trenches, I would simply say that, while these various teams had been firmly locked in their own compartments of confusion, “Ruby had already, long ago (and far more successfully) ‘been there, done that™’”   Ruby built upon Perl without once pretending to be Perl, and it has managed to achieve critical mass.   Meanwhile, Perl-6 finds itself branded as a pretender.

    I would therefore simply offer the following practical opinion:   “‘Perl’ is ‘Perl-5’”   In spite of the use of the registered-trademark with the blessings of the owner of that trademark, the Perl language has reached the same final end that was reached by other abortive language-extensions such as ADD 1 TO COBOL GIVING COBOL, and for exactly the same reasons.   “Time marches on.”

    But, then again ... why did the “Perl-6” team ever seriously suppose that they needed to brand their brainchild as they did ... any more than the “COBOL-plus-plus” people ever conceived that they, too, could possibly make a difference?   There are, in both cases, (probably) billions of lines of source-code written in both languages.   Therefore, what’s the very worst thing that you could possibly do “to all that software?”   Uh huh... “change the language!!”   (However slightly.)

    The “C++” team probably got it right:   they never attempted to call their branchild “C 2.0.”   Ruby, while deeply acknowledging Perl, never pretended to be its first-born son.

    And now, let the downvotes begin ...

      The downvotes will begin because you are the laziest and most ignorant PerlMonk there is. I can write that and be upvoted because every PerlMonk who has been here more than a year knows I'm typing truth and the few who were willing to defend you specifically—on social grounds only, there is no technical defense—are becoming exhausted.

      You know less about Perl 6 than even Perl 5 and your knowledge of any Perl is contradicted by the C or JavaScript idioms you include in your few terrible attempts to write Perl hours or days after seekers of wisdom already have complete, varied answers. If you were a beginner, I'd be a badguy right now, but you're not. You're an avowed expert with decades in who has heard these, and gentle versions of these, admonishments a couple hundred times now. Taken at face value you should be a far more competent hacker than I am but I have corrected your technical assertions many times on a number of on and off topics and I'm an entirely average hacker, well below many of the monks here on the guru totem.

      There is almost nothing you got right in your post except that Perl 6 might have been better named something other than Perl but your question on why it is what it is betrays continuing ignorance. Wall wanted it, that's why. That's it. End of story. The name carried weight and it's possible Perl 6 never would have even left the gate, as late as it did, without that weight. Which would mean no Moose, no mro, no plenty of things. Perl 6 sparked interest in "Perl" which led a lot of new users and traffic to Perl 5 despite idiot assertions to the contrary. It's all goddamned free too and you have never contributed a useful line to any of it so your opinion is the raw sewage of undigested aphorisms.

      You can continue to pretend you are a peer to even the average beginner here—who at least is learning—but you are not and your attempts at building a Perl presence here will now and forever after be nothing but nails in your professional coffin because I've had it and the upvotes, perhaps hubris on my part, of this reply will show that I'm not alone. Good Lord, one could practically make Pope doing nothing but writing rebuttals to every post you've ever written because, as "they"™ say: the jig is up.‡

        "On the other hand, we denounce with righteous indignation and dislike men who are so beguiled and demoralized by the charms of pleasure of the moment, so blinded by desire, that they cannot foresee the pain and trouble that are bound to ensue; and equal blame belongs to those who fail in their duty through weakness of will, which is the same as saying through shrinking from toil and pain. ...

        thanks to generous feeding his jig is going strong
      "...the usual expected firestorm of down-votes..."

      Don't worry. There have been at least four misleaded souls until now that upvoted your unspeakable post.

      «The Crux of the Biscuit is the Apostrophe»

      perl -MCrypt::CBC -E 'say Crypt::CBC->new(-key=>'kgb',-cipher=>"Blowfish")->decrypt_hex($ENV{KARL});'Help