The Perl 6 Summary for the week ending 2005-09-25
Hello all. It's another Monday afternoon, which means I'm writing
another summary. There's no cricket to distract me this week, so I'm
letting iTunes Party Shuffle attempt to distract me instead.
This week in perl6-compiler
Nobody said anything on the list this week. I blame IRC.
Meanwhile, in perl6-internals
About multithreading
Leo pointed everyone at an article about about 'A Fundamental Turn
Toward Concurrency in Software'. Jonathan Worthington liked it.
<http://xrl.us/hq4w>
Bug Wrangling
It's possibly a failing of mine as a summary writer, but I've not been
following Parrot's RT traffic. Luckily, Joshua Hoblitt has volunteered
as a Bug Wrangler and he's hoping to increase the signal/noise ratio. To
that end, he'll be pinging people who reported bugs that are older than
3 or 4 months to find out if they're still current or can be closed. It
sounds like a mammoth task in the short term, but it also sounds like a
very useful project that'll get easier once the big house cleaning has
been done.
He hinted that this is the sort of project that *really* benefits from
having more than one volunteer doing the work.
Later in the week, he posted a bunch of IMCC TODOs.
<http://xrl.us/hq4x>
Tcl, exceptions in leo-ctx5
Andy Dougherty posted some more details about a bug in ParTcl when
running under Leo's branch. The bug seems to depend on whether there's a
slash in the script path passed to ParTcl. There was no response, but
hopefully work continues on fixing it.
<http://xrl.us/hq4y>
[RFC] Debug Segment, HLL Debug segment and Source Segment
Jonathan Worthington posted a discussion of how debugging segments could
work in Parrot in the future. He outlined a suggested unified debug
segment format that should work for both PASM/PIR and high level
language debugging requirements.
Roger Browne applauded Jonathan's efforts and made some further
suggestions.
And then the thread got Warnocked.
<http://xrl.us/hq4z>
Magic is useless unless verifiable
Jonathan Worthington posted a discussion about how Parrot bytecode files
should handle their magic number. At present, apparently, Parrot checks
the magic number only after it's tried to work out word size and
bytecode. Which is somewhat bass ackward. After some discussion, Chip
reckoned that the solution would be to have a magic string rather than a
magic number.
<http://xrl.us/hq42>
"loadlib" and libraries with '.' in the name
Ross McFarland found a problem with "loadlib". Apparently it won't let
you load a library that has a '.' in the name. It turns out that fixing
things robustly isn't quite as straightforward as it at first appears.
Discussion ensued.
Ross posted a patch to RT.
<http://xrl.us/hq43>
<http://xrl.us/hq44>
Find copied and pasted code
That gentleman of great intelligence, sagacity, wit and annoying
capitalization; the one and only chromatic wondered what running PMD's
copy and paste detector plugin on Parrot's .c files would show. If
anyone has run it yet, they haven't reported on its findings, but it
surely won't be long now.
<http://pmd.sf.net/cpd.html>
<http://xrl.us/hq45>
Amber's Ashes Announced
Roger Browne announced the release of Amber for Parrot version 0.2.3a
(Ashes). According to the announcement, Amber's a Eiffel like scripting
language for Parrot. Joe Bob says "Check it out!"
<http://xamber.org/index.html>
<http://xrl.us/hq46>
Meanwhile, in perl6-language
"\(...)"
Oh look, a thread in p6l that's still going more than a fortnight later.
How unusual. This particular instance of the form is nominally about the
behaviour of "\($a, $b)" but various subthreads have drifted onto
discussions of context in general and meaningful whitespace. So far
there has been no discussion of the return value of
"Pin.head.contents.grep -> Angel $a {$a.is_dancing}" but I'm sure it's
only a matter of time.
<http://xrl.us/hq47>
Junctions, patterns and fmap again
Luke continued to discuss Junctions and fmap with Stuart Cook.
<http://xrl.us/hq48>
Conditional wrapper blocks
Yuval Kogman discussed the inelegance of code that reads like:
if $condition { pre }
unconditional midsection;
if $condition { post }
And proposed a possible syntax that could be implemented in a macro. I
confess that I would be taking this thread more seriously if, when I was
writing this summary I had been able to come up with a realistic example
of code that had this problem.
Anyhoo, it sparked a good deal of discussion.
<http://xrl.us/hq49>
Object Model Pictures
Stevan Little's ongoing development of the Perl 6 MetaModel continues to
yield pictures. This week he incorporated Roles into the bigger picture.
<http://xrl.us/hq5a>
"~" and "+" vs. generic eq
In another thread that spilled over from a fortnight ago, Thomas
Sandlass and Yuval Kogman continued to discuss equality, equivalence and
multiple dispatch. There are worse ways of spending the day.
<http://xrl.us/hq5b>
Sort of 'do it once' feature request...
Michele Dondi asked for some way of stopping evaluating a conditional
after it had evaluated to true once. None of the people who replied
seemed to realise that ".." and "..." do exactly that (and a little bit
more).
<http://xrl.us/hq5c>
Stringification, numification and booleanification
The thread on 'Stringification, numification and booleanification' is
this weeks "Thread most likely to still be going in a month's time"
award winner.
It started so simply, with Ingo Blechschmidt asking about the
*-ification of Pairs. And then it exploded. Most recently it's been
discussing the difference between "~$thing" and "$thing", but it's
covered an awful lot of ground. My gut feeling is that default
stringification should be in a form that's useful to a developer when
debugging, but there's arguments to be had in all directions.
<http://xrl.us/hq5d>
Skippable arguments in for loops
Carl Mäsak reported that hcchien on irc had asked about looping through
an array n elements at a time, discarding some. He wondered if
for @a -> undef, $x, $y {...}
would do the trick.
Luke Palmer thought that
for @a -> _, $x, $y {...}
Would be better because, in a multimethod, using "undef" in the way
suggested means "this value must be undef". This being p6l, there were
opinions on both sides. However, "$Luke ~~ @Larry" so I think his
opinion carries the most weight.
<http://xrl.us/hq5e>
pause/cont
Juerd had a moment of clarity and unified a couple of earlier threads
(on conditional wrappers and doing it once) by proposing a pair of
keywords, "pause" and "cont". The semantics are weird, but oh so
powerful. And because I don't want to simply copy and paste his entire
post, I suggest you simply go and read it.
<http://xrl.us/hq5f>
".chars", ".bytes", etc..
Wolverian said that the current way of defining ".chars", ".bytes" and
".elems" didn't make any sense to him. In particular, he thought that,
in a list context they might be better returning the list of things
rather than a simple count of them. Juerd agreed.
<http://xrl.us/hq5g>
"k", "v"
In a Huffman inspired moment, Juerd wondered if we shouldn't abbreviate
"keys" and "key" to "k" and "values" and "value" to "v". Uri Guttman
thought that having single names for things like that wasn't a
desperately good idea. Juerd was convinced.
Are you?
<http://xrl.us/hq5h>
Exceptuations
A resumable continuation by any other name would smell as sweet. Yuval
Kogman coined a new word for them: 'Exceptuations', being a mashup of
Exception and Continuation. He also outlined a how one would use them.
I'm pretty sure we've discussed this stuff before, but there's always a
chance that new light will fall on the subject.
<http://xrl.us/hq5i>
Allomopherencing
Not satisfied with inventing Exceptuations, Yuval invented
Allomopherencing as well. Just don't ask me what it means because I
don't know. I might as well have been reading Derrida in the original
Klingon as Yuval's post an it's ensuing thread. Follow the link, if you
understand it, could you write up a summary and send it to me? Thanks.
You're a star.
<http://xrl.us/hq5j>
Elsewhere
@Larry talks amongst itself
Luke Palmer continues to post minutes from the weekly Perl 6 conference
calls. I'm not going to summarize because it's already rather terse, and
I'm not going to cut and paste either, because although it's terse, it's
surprisingly long. Luke's promised to post these to his blog weekly.
With any luck we'll remember to link to them here as well.
<http://xrl.us/hq5k>
Acknowledgements, apologies and everything else
So, I'm looking for work again. If you need a somewhat rusty perl
programmer, a vaguely competent technical writer with a portfolio
consisting pretty much solely of the back issues of this summary, a
half-decent photographer or an inexperienced Ruby programmer, none of
whom are prepared to travel too far from Gateshead, you know who to ask.
Help Chip
<http://geeksunite.org/> -- Chip still needs help.
The usual coda
If you find these summaries useful or enjoyable, please consider
contributing to the Perl Foundation to help support the development of
Perl.
<http://donate.perl-foundation.org/> -- The Perl Foundation
<http://dev.perl.org/perl6/> -- Perl 6 Development site
Check out my website, it's lovely.
<http://www.bofh.org.uk/>
Vaguely pretty photos by me can be found at:
<http://xrl.us/hq5m>
--
Piers Cawley <[EMAIL PROTECTED]>
http://www.bofh.org.uk/
