This Week in Perl 6, June 21-28, 2005


Long time no see … err, write … uh, read … um … this. Yeah, long time no this. As Piers hinted, two weeks ago I moved. Moving sucks. For those of you who care, I am still in Cambridge; for those of you who care more, I think you misunderstand the summarizer/summary reader relationship. Essentially it revolves around summaries; the summary of my move is Cambridge to Cambridge.

As Piers noted last week, this is a low-volume, high-action week, in no small part due to the hack-a-thons. Last week’s was in Austria, this week’s is near Toronto. Perhaps some nice soul who was actually at these hack-a-thons will summarize them when it is over.

Perl 6 Compiler

PGE Announcements

Patrick announced that PGE now supports grammars and more built-in rules. He even offered to field requests for built-in rules (although he would prefer patches).

Caller’s Context

Gerd Pokorra wanted to know how to determine if his sub is called in void context. He conjectured that want might fill his wants. There is no response yet.

Self-Hosting Goals

Millsa Erlas explained that one good reason for Perl 6 to be self-hosting is that it would allow the people who love it most (Perl hackers) to hack on it. The theory is that low-level languages like C unnecessarily narrow the field of contributors (especially those that only know Perl). People expressed some concerns expressed over confusion about the language Ponie should be written in. No one disputes that this is C.


Indexing Hashtables

Klaas-Jan Stol asked for a clue bat with respect to indexing hash tables in PIR. Joshua Juran and Leo each took a swing.

Parrot Loses with Fedora Core 4

Patrick reported that Fedora Core 4 and Parrot don’t get along well. Leo suggested a possible solution. Patrick has posted no response.

Default Method Resolution Order

Roger Browne wondered what the default MRO order is. Leo provided the answer: left-to-right, depth-first, discard all but the last occurrence of duplicates, divine intervention.

Win32 Tests Failing

Craig the Last-Nameless-One posted a list of failing tests and problems on Windows. Leo provided a few answers.

Method Inheritance Needs Perl Loving

Leo announced a Perl job for the interested: method inheritance in the PMC compiler. This naturally led to discussion of numerical hierarchies. I was a little disappointed that quaternions appeared, but Hamiltonian and Surreal Numbers did not. Honestly, where are our priorities?

Tracing and Debugging Pain

Matt Diephouse posted a general description of the problems he was having with tracing, debugging, and GC. Warnock might apply in a day or two.

Segmented Context and Register Memory

Chip posted a partial reply to Leo’s context and register overhaul patch. Andy Dougherty responded to some of Chip’s finer points. If you find the nuances of C’s pointer pain interesting, this thread is for you.

Improving Parrot’s Test Framework

Chromatic wants to improve Parrot’s test framework by stealing ideas from Test::Class. He wants to know if anyone else has an interest.

setattribute Fails with Multi-Level Inheritance

Roger Browne opened a ticket describing an error with setattribute when using several layers of inheritance.

Register Allocation Bug

Leo opened a ticket for a problem with improper control flow tracking. Bill Coffman wondered whether the new register design is in place yet.

Pass by Value PMCs

Klaas-Jan Stol mused that the new calling conventions could work to allow passing PMCs by value.

Parrot Fall Down Go Boom

Matt Fowles reported a segfaulting Parrot that passes its tests. Sadly, no one solved his problem in the four hours between his posting it and writing the summary.

Perl 6 Language

You Know That, But You Go On

As Piers noted, arguments about ./method versus .method continue. Like Piers, I don’t like ./. I guess I was the only person who liked $^ as the invocant. Ah well, I guess I will just go on summarizing.

Binding Functions

Piers wanted to use a Ruby idiom involving rebinding functions. Damian told him that he could, but also pointed him to wrap.

OO Questions

BÁRTHÁZI András posted a question about method calls in Perl 6. Juerd and Piers provided answers.


Last week’s thread about AUTOLOAD continued. It still seems to be fishing for some official decision.

Magic Mutators and Proxies

Sam Vilain wondered if he could make proxies behave like he wanted to. Luke Palmer explained, yes, but he would need to use binding instead of assignment.

Quasiquoting and PPI

Brad Bowman asked how Quasiquoting and PPI would interact with the AST. Autrijus posted some explanation and Adam Kennedy cleared up some terms.

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