This week's summary

The Perl 6 Summary for the week ending 20040201
    Welcome once again to Gateshead, where the skies are grey, the view is
    uninspiring, and the workmen across the road seem determined to fall off
    the ladder before they get the double glazing fitted.

    But enough of the gay Gateshead life, let's hurry on to the doings of
    the denizens of the perl6-internals mailing list. Who knows, we might
    even visit the inmates of perl6-language later.

  Threading
    To nobody's great surprise, we talked about threading. In particular,
    Gordon Henriksen's concerns about the all around scariness of "morph"
    (and not just in a threading context). I'm not sure I quite understand
    what's being done, but progress is definitely being made.

    Late in the week Dan announced that there were obviously still issues to
    be worked out before we started in on implementation (modulo some
    'obvious' stuff). He also asked for 'real worldish' tests for threading
    in order to get some real numbers for different possible approaches and
    to see if the problem is as bad as it was first thought.

    <http://tinyurl.com/3h9tq>

    <http://tinyurl.com/2774w>

  Embedding vs. extending interface types
    Remember last week's kerfuffle about "Parrot_Interp" vs "Parrot_INTERP"?
    Dan's resolved it be deciding that we'll just call it "Parrot_Interp"
    everywhere. Gordon Henriksen sent in the patch.

    <http://tinyurl.com/ywue7>

  Leo explains
    Will Coleda (and others) have been having problems with data that should
    be inviolate getting clobbered in strange ways. After some effort, Will
    got his offending code down to 22 lines. This let Leo Tötsch work out
    what was going on, and in the referenced post he explained all.
    Essentially, the Copy on Write logic for handling register (and other)
    stacks is broken. The workaround is not to use Continuations and
    Exception Handlers. Fixes are welcome. Please.

    <http://tinyurl.com/2t3a8>

  Testing Signal Handlers
    Leo asked for help with sorting out the testing code for some signal
    handling tests that seemed to be confusing the harness quite badly. Uri
    Guttman came up with some suggested workarounds, as did Mike Schwern.
    Leo found a third way. (If you've ever tried to write test with "fork"
    in it, it's worth taking a look at both Uri and Schwern's answers.

    <http://tinyurl.com/2egso>

  The costs of sharing revisited
    Last week, Leo posted some scary numbers implying that using a shared
    PMC led to terrible slowdowns. This week he posted the latest numbers,
    and things are looking up.

       $ time perl-58-th shared_ref.pl

       real 0m8.694s

       $ time parrot shared_ref.pasm

       real 0m0.375

    (and that's an unoptimized Parrot). Elizabeth Mattijsen was moved to ask
    for a ponie.

    <http://tinyurl.com/3amop>

  Cunning stunts with with UnManagedStruct
    Donning his devious head, Leo demonstrated the use of UnManagedStruct to
    allow for unlimited self-inspection and self-modification of Parrot
    state. Which isn't really something we want to be possible. In the
    opinion of Luke Palmer and Jeff Clites, the costs of removing this
    capability aren't worth paying. As Jeff Clites pointed out, you only use
    UnManagedStructs when you're calling out to a native library, and once
    you introduce a native library all bets are already off.

    <http://tinyurl.com/yt92b>

  Michael Scott: hero of the week
    Over the past few weeks Michael Scott has gradually been making the
    parrot distribution a kinder, gentler place with his sterling efforts to
    tidy up and generally improve the existing documentation. This week he
    rationalized/added documentation for everything in src/ (with the
    exception of malloc.c and malloc-trace.c). He's working on documenting
    examples/ now.

    The response to his announcement was overwhelmingly and understandably
    positive (The consensus is that Mike rocks). Now if we can just *keep*
    everything in such good condition...

    <http://tinyurl.com/2pevc>

  Parrot DBDI announced
    Tim "Perl DBI" Bunce announced the Parrot DBDI Project: A Database
    Driver Interface for Parrot. The goal is to have a common Parrot level
    interface to database drivers which can then be reused by different
    language specific database interfaces. For further details read the
    post; it's jolly good. And bravo Tim.

    <http://tinyurl.com/23zq3>

  Internal exception handlers
    Leo posted a set of macros for doing exception handling in the parrot
    core using "TRY/CATCH/THROW" etc. and asked for comments. So far he's
    been Warnocked.

    <http://tinyurl.com/2z57k>

  SDL bindings
    After Leo fixed the struct PMCs for him, chromatic has proceeded apace
    to implement SDL wrappers in Parrot. He's reached the point where he has
    code that can create an SDL window and blit a blue rectangle onto it.
    Leo applied his patches. Check out examples/pni/sdl_blue_rectangle.imc
    if you're interested.

    <http://tinyurl.com/yretd>

Meanwhile, in perl6-language
    Discussions continued to test the encode setups of the participants'
    mail readers...

  Semantics of vector operations
    A sub-thread of the discussion of the semantics of vector operations
    turned into a discussion of the meaning of 'vector' which has different
    meanings depending on whether you're a mathematician or Seymour Cray.

    Another sub-thread discussed the possible ASCII alternatives for "«"
    and "»". I'm afraid I'm going to bottle out of attempting to summarize
    the various alternatives suggested, if only because I used up all my POD
    escape-fu last week. It looks like the "<<" and ">>" alternatives might
    be about to bite the dust in favour of an as yet undecided, less
    ambiguous, new scheme. Larry hasn't ruled on it yet though.

    <http://tinyurl.com/29yau>

Acknowledgements, Apologies, Announcements
    I'd just like to announce that, if you haven't seen Eliza Carthy perform
    life, you owe it to yourself to rectify that. We went to see her last
    night and it's bucked me up enormously.

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• This week's summary by The Perl 6 Summarizer
• This week's summary by The Perl 6 Summarizer