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Haskell to Perl 6

docs.perl6.org

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Re: Haskell to Perl 6

#51

Post by Riverheart »

herrosheep wrote: post #3

I'd like to hear opinions on how the use of sigils and the other syntax oddities like Int:D, Int:U, given, when, etc improves the codabliity/readability of Perl 6 vs other languages. The examples vs Haskell are not helping me understand. Personally I don't think the added verbosity is helping in any way.

Perl6's use of sigils seems excessive to me but I do like sigils for variables. It acts like a namespace between similarly named constructs. I know for instance WebClient is a class and $WebClient contains an instance of it. I also like how it makes it easy for syntax highlighters to identify variables from classes and keywords.

Re: Haskell to Perl 6

#52

Post by colomon »

herrosheep wrote: post #3

I'd like to hear opinions on how the use of sigils and the other syntax oddities like Int:D, Int:U, given, when, etc improves the codabliity/readability of Perl 6 vs other languages. The examples vs Haskell are not helping me understand. Personally I don't think the added verbosity is helping in any way.

I don't get the given/when part of this comment at all? given/when is exactly like C's switch/case, except the names are better and it's at least an order of magnitude more powerful.

It's 100% not added verbosity in any way. Added complexity, sure, but it's a pretty straightforward application of some of the main ideas of the language, usable in the standard C-language-family way out of the box, and powerful and flexible when you understand it.

Re: Haskell to Perl 6

#53

Post by mmirate »

kbenson wrote: post #37
ricardobeat wrote: post #19

Earlier quoted context omitted.

Except the resulting code will look nothing like “the humans say it”, and instead will be a cryptic charade requiring a ton of knowledge to decipher - ending up being neither natural language nor machine code.

> Except the resulting code will look nothing like “the humans say it”, Actually, I find it maps rather directly to how a lot of people explain things. For example, "Examine each number, and as long as it's greater than 10 and odd, then pass it to the the work function." for my $number ( @numbers ) { next unless $number > 10; next unless $number % 2; work($number); } Perl generally allows you to structure your code a…

That ought to be a oneliner in any sane language today:

    numbers.into_iter().filter(|n| n>10 && n%2!=0).for_each(work);

    map work . filter ((/=0) . (`mod` 2)) . filter (>10) $ numbers
Insert tirade about how for-loops are free to do so much that they are slower-to-comprehend than specific-purpose iterator/list functions, here.

Re: Haskell to Perl 6

#54

Post by kev6168 »

4thaccount wrote: post #50
kev6168 wrote: post #43

Earlier quoted context omitted.

It was tongue in cheek, haha... I was only frustrated by my own inability to get the hang of Perl 6. As an old casual fan of Perl, I still want to take another shot at learning it very much.

The perl6intro website shows you the essentials of what you need and the ecosystem has matured a lot since 2014 as well as many good books being published. Laurent Rosenfield has a Think Perl6 book that you can buy in paper or read online for free. If you can already code, getting proficient in basic Perl6 is easy. Becoming a master is outside my current grasp.

Thanks for the recommendations.

One liners are fun, and life-saving. I am curious about this aspect compared to Perl 5. With Perl 6's new syntax and language features, can we still easily [ab]use one liners for fun and profit?

Re: Haskell to Perl 6

#55

Post by dTal »

AnimalMuppet wrote: post #16
nine_k wrote: post #9

Earlier quoted context omitted.

Perl has never been about uniformity. Perl is a great experiment in language design, or, rather, a battery of experiments. It's the opposite of a cleanly designed language.

No, it's designed. It's just not designed the way everyone expects a computer language to be designed. It was designed by a linguist. He produced a language with some of the flexibility (and messiness) of human languages, which is completely foreign as a goal to other languages. One of the places this shows up to me is being able to say "it" (in essence). That is, we humans, when talking to each other, we say things…

I'm not sure your definition of 'it' (that is, a default) matches how 'it' is actually used. 'It' is a locally scoped name binding to a previously mentioned symbol. In English, the referent of 'it' is sometimes ambiguous, requiring contextual intelligence that computers lack, so programming languages with 'it' need to be more precise.

Here's 'it' in lisp: https://en.wikipedia.org/wiki/Anaphoric_macro

Re: Haskell to Perl 6

#58

Post by cygx »

uryga wrote: post #40
kqr wrote: post #26

Earlier quoted context omitted.

I have no problem reading that. Sure, I dont understand it in fine technical detail (what's Mu? An implementation of Perl? A codename for Perl 6?) But I believe I understand enough of it to start using it. This specific example seems similar to the __repr__ vs __str__ thing in Python, and not very alien at all.

`Mu` is perl6's `Object` ("mu" ≈ "nothing" in chinese/japanese). cute, but alien

Also, "most undefined".
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