The Perl 6 Summary of the week ending 20031012
Good afternoon readers. You find me sitting comfortably and tired after
a vaguely frantic week involving large amounts of new (and huge)
equipment, the delivery of a new Mini Cooper, and four days offline at a
large format photography workshop (photos will be going online soonish,
if you're interested). All of which hopefully goes some way to
explaining the fact that I've only just started writing the summary at
ten to four on Tuesday.
We start (and finish) with the internals list.
New PMC compiler
Leo Tötsch isn't exactly happy with the current classes/pmc2c.pl PMC
compiler. He outlined the drawbacks as he sees them, proposed a scheme
for reimplementing it, and asked for comments. Dan said that so long as
the resulting code is clearer than the current PMC compiler, Leo should
go for it. So he did.
http://xrl.us/w5m
The Status of Language, Credit Where It's Due
Melvin Smith has added a LANGUAGES.STATUS file in the languages/
subdirectory and asked for language authors to add summaries of the
various language subdirectories to the file.
Fresh from this success he added a CREDITS file for giving credit where
it's due. Rumours of an entry reading
N: Leon Brocard
D: Running Joke
are (currently) false.
Later in the week, LANGUAGES.STATUS was extended to cover both the
languages found in languages/ but any other languages that people were
working on and making available outside the Parrot distribution for
whatever reason.
http://xrl.us/w5n
http://xrl.us/w5o
Binary MMD vtable functions are go
Dan's solved an off by one error with multimethod dispatch and checked
everything in, so now Parrot has working two argument multimethod
dispatch. Hurrah! There's still lots it doesn't do mind, but getting
started is always good.
http://xrl.us/w5p
Attacking the Unicode Monster
Dan's searching for a Unicode Monster Wrangler. ICU is now building on
enough platforms that the time has come to build an encoding and
chartype library for it. Volunteers gratefully received.
Jeff Clites and Michael Scott have both been poking at it a bit;
hopefully they'll be able to put their heads together and emerge with
something wonderful.
http://xrl.us/w5q
More NCI stuff
Dan's been a busy boy this week. Parrot now comes with
library/postgres.pasm, an interface to libpq (the C library that talks
to Postgres). These NCI interface files are currently built by hand. Tim
Bunce wondered if it might be possible to ExtUtils::XSBuilder to
generate PASM from C header files instead of XS code. It was generally
agreed that this would be a cool thing, but it's not been done yet.
http://xrl.us/w5r
http://www.postgresql.org/
The Parrot Stack and Z-Machine
Amir Karger is working on getting his head 'round the Z-Machine (The
virtual machine that runs Zork and the other Infocom games, amongst
others) by writing code to translate Z-code into a Perl executable. He
came up with a problem with saving and restoring the stack in order to
save the game state.
http://xrl.us/w5s
References
Leo's been giving the Reference PMC a hard look and, as a result,
suggests adding a couple of handy ops, "deref" and "ref" (which finds
the type of the thing the reference refers to) to use with them. Melvin
Smith pointed out that, actually we only needed one of Leo's proposed
ops. On the other hand, as Nicholas Clark pointed out, "ref" avoids the
need to grab another PMC register, which may cause a register spill. On
the gripping hand, Melvin argued that spillage is pretty rare with the
number of registers Parrot has.
http://xrl.us/w5t
The program's ending! DESTROY everything!
Jürgen Bömmels found a subtle bug where objects that had active
destruction weren't having their destroy functions called correctly (at
all) when parrot terminated. After a couple of goes round the '"this
would be so much easier if we were all in the same room"
misunderstanding' loop, the Right Thing was settled upon and
implemented.
http://xrl.us/w5u
An interesting task for the evil
One of the things that Dan would really like to be able to promise with
Parrot's GC is ordered destruction. Taking a leaf out of my lightning
talk on complexity management, he noted that "we just need to order the
PMCs before destroying them, to make sure we don't call the destructor
for a PMC before we destroy the things that depend on it" and asked for
volunteers to implement it.
Dave Mitchell spoilt the understatement party by pointing out that, in
the presence of circular dependencies things got a little more
complicated (but not that much more complicated, Dan claims).
Nobody's actually volunteered yet.
http://xrl.us/w5v
Parrot gets "pioctl"
Melvin Smith added a "pioctl" op for general purpose IO manipulation in
the style of the UNIX "ioctl" syscall. Dan reckoned it was almost
certainly time to start thinking about a better API (though we're not
sure if that's because he doesn't like "ioctl" as a name). Steve Fink
suggested using keyed access to the IO PMC, so you could do
set IO, P0[.BUFSIZE]
set P0[.BUFSIZE], 8192
Steve later backed away from this suggestion, suggesting that maybe
"get/setprop" fit the semantics better, but Leo thought that
'fundamentals' like buffer size belonged as keyed access, with
properties being reserved for setting up things like encoding layers.
http://xrl.us/w5w
PCC and IMC
Gregor N. Purdy suggested that, instead of going through the hassle of
explicitly setting up a function call under the parrot calling
conventions, one could call the the function in the style of a macro
call. Leo wasn't keen, IMCC is still an assembler after all (just a very
sophisticated one). It looks like, unless Dan rules otherwise, we're
going to stick with the current explicit method of function invocation
setup, and human parrot programmers will just have to set up convenience
macros explicitly.
http://xrl.us/w5x
Meanwhile in perl6-language
Acknowledgements, Announcements, Apologies, Alliteration
I'm really sorry I used the '...' joke about perl6-language again. Write
something people!
Tuesday continues to be the new Monday, and will probably remain so for
a while.
http://www.bofh.org.uk:8080/ will hopefully be hosting my photos from
the weekend's workshop.
If you found this summary valuable, you might like to consider one or
more of the following suggestions:
* Get involved. There's at least two calls for volunteers out at the
moment related to Parrot. Okay, they're not necessarily easy, but if
you turn up on the lists (check http://dev.perl.org/perl6/ and
http://www.parrotcode.org/ for subscription details) and offer to
help I'm sure we'll find something that needs doing.
* Support Larry, Dan, Damian and company by donating to the Perl
Foundation at http://donate.perl-foundation.org/. Fun as hacking
Perl 6 no doubt is, it's very easy to get distracted from it by the
pressing need to feed yourself.
* Boost my ego. Praise my photos/this summary/my lackadaisical weblog.
Suggest improvements, point out my grammatical howlers, hire me to
do cool stuff, press gifts upon me. Contact me at
[EMAIL PROTECTED], unless you're a spamming scumbag I can
pretty much promise you a prompt response. Assuming I'm not out
hooning 'round the countryside in my new car...
