Comment by Ulti | Hacker News Reader

Comment by Ulti | Hacker News Reader

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Quoting is highly generalised in Perl 6. Comments happen to be more feature rich and dynamic than other languages. They aren't simply ignored by the compiler but completely parsed and used in a variety of ways. The flexibility looks odd because it's meant more for quoted string interpolation, but reuses the same mechanism for comments. Generality of concepts is a common theme throughout Perl 6, if something looks round and spins it should be a wheel.

For example all of the literate style POD6 comments are accessible within a variable as a fully structured tree in the $=pod variable. The 'q' quoting context in the main language allows you to use any matched quote/bracket from unicode as the markers of the start and end of a string or regex, or comments as you've picked up on.

This is super helpful if you want all sorts of weird quotes and brackets inside of a string and still have it interpolated for variables for example.

    say q⧚This string has a "'weirdly quoted bit in'"!⧛;

Will print out:

    This string has a "'weirdly quoted bit in'"!

To see some examples of how extreme you can have these characters be from unicode check out http://xahlee.info/comp/unicode_matching_brackets.html

As someone that has spend significant time in Perl5, why would they use something like `$=pod`? I get that the name starts with '=' just like the pod syntax, but that doesn't mean it needs to be in the variable name. I would almost just rather that they have some sort of namespace just for 'special' variables like Python with their 'dunder' variables (i.e. double-underscore like __doc__).

I find it charming. It doesn't need to be the way that particular special variable is done, but twigils are a thing in Perl 6, and I think this is a reasonable use of them.

You still have to check the docs for the dunder variables in Python. Having the same special character convention (like __var__) doesn't magically make me aware of what they all are and what they all mean. And, I've done enough Python programming to know it's a crapshoot to google for them (just as it's a crapshoot to google for sigils and twigils in Perl). You just have to know where to look for the right docs or know who to ask for where to look for the right docs (perldoc perlvar, in the case of Perl...I assume there's something similar for Perl 6, and I don't remember what it is for Python).

There is a special namespace like that. In fact, there are several, and they are selected by placing a second specials character after the sigil.

I've seen parsed comments in TCL and I didn't like them there. Honestly this generalization sounds like another way to write-only code, especially the unicode brackets.

Only if you're the kind of moron that would do it to begin with. At no point is anyone saying you should use weird quoting in comments at all. The parsed comments are used to populate dynamic documentation related to functions and classes that you can inspect at runtime. What's so bad about that?

Hi Ultimatt,

I was saddened when I saw that someone who loves Perl 6 used the word 'moron'. It is "closely tied with the American eugenics movement" according to wikipedia and is a deprecated diagnostic categorization of someone having a mental age of 8-12 years old -- an audience we supposedly wish to attract, not repel.

I'm not at all meaning any moral judgement. I've used such words myself in the past in much more terrible and significant ways. I'm just feeling low about how unkind we can sometimes be to others and sad to see these few opportunities on HN to discuss Perl 6 ending up sidetracked not only by what might be called trolling but also by seeing P6ers (including me sometimes) making things worse.

I thank you for and want to help sustain your passion about the technical aspects of Perl 6. I'm also hoping to encourage more compassionate ways of connecting with all folk, including trolls, and to being passionate about that too.

And a merry new year to all. :)

All insults have a similar history - "idiot" is the same kind of thing, just from a little further back in history.

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