Re: Naming debate- what's the location for it?

[Patrick R. Michaud]

On Wed, Feb 14, 2018 at 05:55:54PM +, raiph mellor wrote:
> (Perl) Rakudo
> ===
> 
> If jnthn and pmichaud and larry can warm to this idea, then:
> [...]
> The 'Perl' could be dropped from Rakudo specific propaganda,
> calling the language just Rakudo instead, to reinforce that it refers
> to 6e and beyond. But the Perl could be retained in any material
> covering both Raptor and Rakudo as a reunified tech / community.

FWIW, I am VERY MUCH AGAINST the idea of naming a language after its 
implementation.  I've seen the confusion it causes in other environments and we 
ought not repeat that mistake here, especially since we don't have to.

Whatever things end up being called, don't confuse the implementation(s) with 
the language definition.

Pm

Re: To :D or not to :D

[Patrick R. Michaud]

On Tue, Oct 13, 2015 at 12:32:01AM +0200, Mark Overmeer wrote:
> Yes, that what I started realizing when I saw all the pain Perl6 goes to
> ignore the existence of a real "undef" in the language.  (I follow Perl6
> from a short distance since its start, read all original designs, but
> this penny did not drop before, sorry)

Actually, it's the other way around.  Perl 6 is not trying to ignore
the existence of an "undef", it's recognizing that there are in fact
many different kinds of undef.  It's the languages that think there's
only one "real undef" that are confused.  :)

> The reasoning behind the output of
>  my $a; $a.say; $a = 1; $a.saybeing  (Any) \n 1 \n
> Which actually means
> "unstantiated (Any)" versus "instantiated (Int) value=1"
> for me personally painfully imbalanced.
> 
> my Car $a; my Car $b;   Now I have two different types.  

Not really, you have two variables, both of which have been
initialized to the same (undefined) Car object.  It's not
much different than

   my Int $a; my Int $b;  $a = $b = 1;

where $a and $b end up being variables that contain the same
Int object.

> Is there any precedence in a succesful programming language where types
> and values get mixed-up this way?  

I think Self would be the (pardon the pun) prototypical example, and
it's also a common feature of JavaScript.  As to whether there is
precedence in other "successful" programming languages -- to me part 
of Perl's legacy has always been that it offers exotic (at the time) 
features that other "successful" languages didn't provide.  Perl has 
often been the tip of the spear in making "exotic" features commonplace.  :)

Larry and the other OO experts can probably comment on this in more 
detail; but this construction of types allows Perl 6 to incorporate
a lot more features of prototype-based languages than the traditional
class-based model.  I suspect it's also related to a proper 
implementation of mixins and roles.

> For me, a "Car" is not "a vehicle which is not yet there", but is a
> featural and functional template of a thing.  The template describes the
> interface of a car, not the instance of a car.  A type is scientific,
> an object is dull facts.  Is that an old-fashioned, traditional idea
> to be abandoned?

Perl 6 still has classes and instances, but Perl 6 also adds the 
ability to represent undefined instances of a type (or, rephrased,
to have typed "undefs").  Perl 6 then binds the commonly-used 
identifier (e.g., C) to an undefined instance rather than the 
class object that defines the instances.  Once you accept that model,
it seems to work out very well in practice.

When we need to communicate with the class definition (rather than 
an instance), there's a convenient .^foo syntax that allows us to 
accomplish this, which works on any instance (defined or undefined).
That becomes important when you want to do something like:

my Research $a;
say $a.methods();   # invoke "methods" defined by Research
say Research.methods(); # same as above
say $a.^methods();  # return a list of methods for Research objects

If Research refers instead to the class definition, then the 
method namespaces for instances and classes begin to clash, and
we have to introduce all sorts of disambiguation for that.

Pm

Re: To :D or not to :D

[Patrick R. Michaud]

On Mon, Oct 12, 2015 at 09:51:13PM +0200, Mark Overmeer wrote:
> > method new(MyClassHere:U: *@args) { ... }
> > 
> > in the constructor, which would be quite hostile to newbies. It's still
> > not clear to me how to avoid that.
> 
> It is also unclear to me what this means.  It is a method which requires
> and undef parameter?

Because of the second colon, it's a method accepting an undef invocant.
This is what would be needed in order for

MyClassHere.new(...)

to work the way you expect (since MyClassHere is undefined).

> > Another concern is that if "everything" defaults to :D, then classes
> > (and other type objects) aren't really first class objects anymore,
> > which is a really neat thing to have.
> 
> Can you give me an example?  Many other languages are capable to live
> without undef and have first class type objects.  

Keep in mind that what Perl 6 calls a "type object" isn't quite the
same as class objects in other languages -- a Perl 6 typename is
really an undefined instance of a class.  In other words, the
identifiers C, C, C etc. refer to instances of
those classes just like the literals C<3>, C<4/5>, and C<[1,2,3]> are
instances of those classes.  They share the same method spaces.

Pm

Re: memory leak I think.

[Patrick R. Michaud]

On Thu, Dec 19, 2013 at 11:27:32AM +0800, Richard Hainsworth wrote:
> I've been running a perl6 program that runs through a loop, dumps
> intermediate results and starts again with new initialisation
> values.
> [...]
> Looking at system resources, the program chews up memory resources
> continually.
> 
> a) Is this a known problem due to garbage collection problems?

If you're using Rakudo on Parrot, then the likely cause of what
you are seeing is due to the way Parrot manages memory.  Parrot
tends to allocate memory pools up to a certain limit (based on
system resources) and never releases any of that allocated memory 
back to the system until the process terminates.

So even though Rakudo is likely releasing the resources back
to Parrot, Parrot doesn't release them back to the system.  Parrot
will start re-using the allocated memory for new objects, however,
once it's reached the resource limit mentioned above.

Pm

Re: Licensing: Perl 6 specification and test suite

[Patrick R. Michaud]

On Tue, Nov 05, 2013 at 11:00:59AM -0600, Patrick R. Michaud wrote:
> > Forking the documentation, or creating derivative works, shouldn't be a
> > problem, as long as it doesn't change the specification in itself, and
> > thereby create confusion regarding what the Perl 6 specification is.
> 
> ...and this is the exact reason for that wish.  The documentation isn't
> the specification at all -- the test suite is.

I should probably clarify.  I think that referring to the Synopses
as "specification" *increases* confusion on the issue, because
it's the test suite that defines the language, not the Synopses.

In some sense, perhaps the Synopses should be considered just
another (human-readable prose) "implementation" of Perl 6.  Just
like any other Perl 6 implementation, a discrepancy between the
Synopses and the test suite means that one of them needs updating
(based on experience and evolution), but ultimately it's the test
suite that determines what is or is not correct in the Perl 6
specification.

Pm

Re: Licensing: Perl 6 specification and test suite

[Patrick R. Michaud]

On Tue, Nov 05, 2013 at 04:21:12PM +0100, Jan Ingvoldstad wrote:
> Considering that the specification is sortof actually a language
> specification, I think there should at least be some terms regarding how
> this should apply.

Just to nit semantics a bit and push a little harder on something I've
generally not pushed too much in the past...

I believe that the Perl 6 language "specification" is actually the 
test suite.  Synopsis 1 even indicates this somewhat explicitly:  
"Perl 6 is anything that passes the official test suite"  and
"... Perl 6 is defined primarily by its desired semantics, not by
accidents of history."

To me, the Synopses are primarily a detailed language description,
and I'm increasingly wishing we wouldn't consider them as "the 
language specification"...

> Forking the documentation, or creating derivative works, shouldn't be a
> problem, as long as it doesn't change the specification in itself, and
> thereby create confusion regarding what the Perl 6 specification is.

...and this is the exact reason for that wish.  The documentation isn't
the specification at all -- the test suite is.

Pm

Re: Licensing: Perl 6 specification and test suite

[Patrick R. Michaud]

On Tue, Nov 05, 2013 at 03:36:47PM +0100, Moritz Lenz wrote:
> Somehow I have always worked under the assumption that it is under
> the Artistic License 2, just as Rakudo and NQP, and community
> concensus seem to agree with me. Therefor I've added an AL2 LICENSE
> file to the perl6/roast repository, and I hope that any former or
> current contributor that disagrees with the choice of license speaks
> up soon.

Just to add my +1:  I totally agree that perl6/roast is AL2, and
I believe that to be entirely consistent with the way things were
in the Pugs repository at the time of the split.

Pm

Re: Class attribute introspection

[Patrick R. Michaud]

On Mon, Oct 28, 2013 at 05:17:37PM +0400, Richard Hainsworth wrote:
> Pardon the ignorance, but what is "the MOP". I sometimes get floored
> by the jargon.

Whatever answer we get should go into S99.  

https://github.com/perl6/specs/blob/master/S99-glossary.pod

Pm

Re: Introduction to Synopses

[Patrick R. Michaud]

On Mon, Sep 30, 2013 at 02:03:43AM +0800, Richard Hainsworth wrote:
> Not wising to disagree with PM, but "|docs/feather/syn_index.html"
> states on line 1:|
> "The Synopsis documents are to be taken as the formal specification
> for Perl 6 implementations"

What follows is just my opinion, there's plenty of room for reasonable
disagreement.

Over the last couple of years I've come to disagree with this
statement in syn_index.html .  

Informally we often talk about the synopses as being "the official 
spec", and I'm as guilty of that as anyone else.  Even the name of
the repository holding the synopses is given as "specs".  But as all
of us know, some parts of the synopses are incredibly slushy, or
even quite fluid, and so it's not something that people can really
treat as truly "specification".  And there are countless parts of
the synopses that have radically changed as a result of lessons
learned in implementation... (I can tell long stories about S05!).

Thus it was recognized early on (in Synopsis 1) that acceptance tests
provide a far more objective measure of specification conformance
than an English description.  There are likely things that need to
be "spec" that cannot be fully captured by testing... but I still
believe that the test suite should be paramount.

> Perl6 language development is a gradual change of specification,
> test suite and implementation until the specification is proven by
> implementations, which all pass the test suite, for some sense of
> 'proven' and some set of 'implementations'.
> 
> A "version" of Perl6 is "described" by the combination of a
> "specification suite" and a "test suite".

I'd prefer that versions of Perl 6 be captured solely by the test 
suite.  I don't know how practical this is, though.  I don't like
the notion of "specification suite"... it feels too nebulous to me.

> A version of Perl6 is declared to be ready when there is at least
> one full implementation exists that generates code considered to be
> sufficiently fast and memory efficient.

I also don't like the idea of defining "readiness" in the abstract.
Something is "ready" when it is capable of solving the problem(s) to
which it is being put.

Pm

Re: Introduction to Synopses

[Patrick R. Michaud]

On Sun, Sep 29, 2013 at 01:28:48PM +0800, Richard Hainsworth wrote:
> However, the Synopses are now primary specification and the
> Apocalypses have only historical significance. Also there are more
> Synopses than Apocalypses.

One correction:  The test suite ("roast") is the primary specification
(see Synopsis 1).  

To me, the Synopses are the English description of our understanding 
of the specification / language, as well as a roadmap for growth in the
future.

Pm

Re: Are set operations needed?

[Patrick R. Michaud]

On Thu, Jul 18, 2013 at 07:07:20PM +0800, Richard Hainsworth wrote:
> I wondered whether the desire to have sets in perl6 was driven by
> mathematical fashion sensitivity (in some roundabout unconscious
> way) and because sets are important to mathematical foundations.
> [...]
> Sets do not implement well on a computer.

I suspect that these two statements, taken together, give a large
part of the reason Perl 6 has sets implemented in the core.
They're an important part of the mathematics that program(mer)s 
use to solve problems, and without a common foundation it's
easy to come up with many suboptimal implementations.  A similar
argument exists for Temporal and date/time objects.

Also, in earlier days of Perl 6 discussions, we discovered
that people would learn about junctions and then try to use them
to solve set-based problems.  This frequently led to many dead-end
discussions about trying to generalize junctions to that purpose.
Having sets and set operators explicitly included in the core is
intended to also guide people away from the false path of thinking
that junctions are the Perl 6 vehicle for set-based operators.

Pm

Re: Rakudo Star 2013.05 released

[Patrick R. Michaud]

On Thu, May 30, 2013 at 11:08:13PM -0500, Patrick R. Michaud wrote:
> This Star release includes [release 2013.05] of the
> [Rakudo Perl 6 compiler], version 5.2.0 of the [Parrot Virtual
> Machine] ...

Oops.  The 2013.05 release actually contains Parrot 5.3.0.

Sorry about the typo.

Pm

Rakudo Star 2013.05 released

[Patrick R. Michaud]

## A useful, usable, "early adopter" distribution of Perl 6

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the May 2013 release of "Rakudo Star", a useful and usable
distribution of Perl 6. The tarball and Windows .MSI for the May 2013 
release are available from . 

In the Perl 6 world, we make a distinction between the language
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  This Star release includes [release 2013.05] of the
[Rakudo Perl 6 compiler], version 5.2.0 of the [Parrot Virtual
Machine], plus various modules, documentation, and other resources
collected from the Perl 6 community.

[release 2013.05]:
https://github.com/rakudo/rakudo/blob/nom/docs/announce/2013.05.md
[Rakudo Perl 6 compiler]: http://github.com/rakudo/rakudo
[Parrot Virtual Machine]: http://parrot.org

Some of the new features added to this release include:

* The ?-quantifier on regex captures now returns a single Match object 
  (formerly returned an array).  Use `** 0..1` to get the old behavior.
* Failed matches return Nil instead of a false Match object.
* Rakudo warns when pure expressions are used in sink context
* .substr(...) now correctly accepts whatever-star closures
* Implemented shellwords postcircumfix (%h<< $x 'foo bar' >>)
* Defining operators spelled like the empty string is now illegal
* Array interpolations now properly do LTM
* Autothread "none" and "all" junctions before "any" and "one"
* Helpful error if you write "else if"/"elif" instead of "elsif"
* Throw exception if a Range is used as a Range endpoint
* Corrected argument order in IO.seek
* wrap low level VM objects in ForeignCode, allowing perl6 OO calls on them
* for loops are eager again
* add link and symlink to IO
* add Capture.Bool()
* improvements to DUMP()
* various optimizations in the optimizer and the runtime
* smartmatch against list now supports Whatever wildcards
* IO::Spec, a port of Perl 5's File::Spec
* regex special characters can be used as delimiters
* allow slice with :exists adverb on hashes
* added 125 extra opening/closing bracket-pairs

This release also contains a range of bug fixes, improvements to error
reporting and better failure modes.

The following features have been deprecated or modified from previous
releases due to changes in the Perl 6 specification, and are planned
to be removed or changed as follows:

  * `postcircumfix:<[ ]>` and `postcircumfix:<{ }>` will become
multi-subs rather than multi-methods. Both at_pos and at_key will
remain methods.

  * Unary hyper ops currently descend into nested arrays and hashes.
This will change to make them equivalent to a one-level map.

  * The Str.ucfirst builtin is deprecated; it will be replaced by
Str.tc.

  * Leading whitespace in rules and under :sigspace will no longer be
converted to `<.ws>`.  For existing regexes that expect this
conversion, add a `` in front of leading whitespace to make it
meta again.

  * The result of failed matches will be Nil instead of a Match
object returning boolean False.

There are some key features of Perl 6 that Rakudo Star does not yet
handle appropriately, although they will appear in upcoming releases.
Some of the not-quite-there features include:

  * advanced macros
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * interactive readline that understands Unicode
  * non-blocking I/O
  * much of Synopsis 9

There is an online resource at 
that lists the known implemented and missing features of Rakudo and
other Perl 6 implementations.

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are many
that we've missed.  Bug reports about missing and broken features are
welcomed at .

See  for links to much more information about
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.  A
draft of a Perl 6 book is available as docs/UsingPerl6-draft.pdf in
the release tarball.

The development team thanks all of the contributors and sponsors for
making Rakudo Star possible.  If you would like to contribute, see
, ask on the 
mailing list, or join us on IRC \#perl6 on freenode.

Re: Panda on Windows

[Patrick R. Michaud]

On Wed, Mar 20, 2013 at 01:49:21PM +0100, Tadeusz Sośnierz wrote:
> On 03/20/2013 10:21 AM, phi...@free.fr wrote:
> >Hello,
> >
> >when I type "panda" on the Windows command line, I get the following message:
> >
> >D:\users\me>panda
> >connect failed: A connection attempt failed because the connected party did 
> >not properly respond after a period of time, or established conn
> >ection failed because connected host has failed to respond.
> 
> Hi,
> are you sure that you aren't behind some firewall, or restricting proxy?

Out of curiosity, is there a way to get the error message to indicate
what panda was attempting to connect *to*?

   connect failed: A connection attempt to somehost.org failed

Pm

Re: Perl 6 in Perl 6?

[Patrick R. Michaud]

On Thu, Oct 18, 2012 at 09:59:21AM +0200, Moritz Lenz wrote:
> 
> On 10/18/2012 09:02 AM, Darren Duncan wrote:
> >Something (PyPy et al) got me wondering, is it a goal in the Perl
> >community before too long to have a (compiling) implementation of Perl 6
> >written entirely in Perl 6?
> 
> A fair amount of the two major Perl 6 compilers, Rakudo and Niecza,
> are already written in Perl 6.
> Both also contain runtime code written in the "native" underlying
> language (C/C#), and plans to get rid of that are not realistic
> right now.

As a quick data point: Rakudo's codebase (compiler+CORE setting)
currently contains around 4,309 lines of C code (*.c, *.h, *.pmc) 
and 24,406 lines of Perl 6 code (*.pm, *.nqp).  

So, 85% of Rakudo is written in Perl 6 and 15% in C-ish languages.

Pm

Rakudo Star 2012.09 released

[Patrick R. Michaud]

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the September 2012 release of "Rakudo Star", a useful and
usable distribution of Perl 6.  The tarball for the September 2012
release is available from .
A Windows .MSI version of Rakudo star will usually appear in
the downloads area shortly after the tarball release.

In the Perl 6 world, we make a distinction between the language 
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  This Star release includes release 2012.09.1 [0] of the
Rakudo Perl 6 compiler [1], version 4.6.0 of the Parrot Virtual
Machine [2], and various modules, documentation, and other
resources collected from the Perl 6 community.

Some of the new features added to this release include:

* Basic macro support!

* Support for Perl 5 (m:P5/.../) regex syntax!

* Indirect type names in routine and type declarations are supported.

* We support the "is export" trait on constant declarations.

* The "is hidden" and base traits are supported.

* Str.wordcase, is-prime, and expmod are implemented.

* Compilation is slightly faster than before.

* Tie-breaking with constraints selects the first matching
  constraint rather than demanding mutual exclusion.

* Smart matching against Signature literals, and binding to Signatures
  in declarators.

This release also contains a range of bug fixes, improvements to error
reporting and better failure modes. More exceptions are thrown as typed
exceptions, and more meta-model errors have been fixed to properly
report line numbers.

The following features have been deprecated or modified from previous
releases due to changes in the Perl 6 specification, and are being removed
or changed as follows:

* Iterable is now a role instead of a class, and no longer inherits 
  from Cool.

* Parameters preceded by a | or \ can no longer have a sigil.

* IO::Path.dir (which returns the directory part of the path) has been
  renamed to IO::Path.directory.  IO::Path.dir will be removed or
  re-purposed.

* The Str.ucfirst builtin is deprecated; it will be replaced by Str.tc.

* The (experimental) LAZY statement prefix will soon be removed.

* Leading whitespace in rules and under :sigspace will no longer be
  converted to <.ws> .  For existing regexes that expect this conversion,
  add a  in front of leading whitespace to make it meta again.

* The ?-quantifier on captures in regexes currently binds the capture
  slot to a List containing either zero or one Match objects; i.e., it
  is equivalent to "** 0..1".  In the future, the ?-quantifier will
  bind the slot directly to a captured Match or to Nil.  Existing code
  can manage the transition by changing existing ?-quantifiers to
  use "** 0..1", which will continue to return a List of matches.

There are some key features of Perl 6 that Rakudo Star does not
yet handle appropriately, although they will appear in upcoming
releases.  Some of the not-quite-there features include:

  * advanced macros
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * interactive readline that understands Unicode
  * non-blocking I/O
  * much of Synopsis 9

There is an online resource at http://perl6.org/compilers/features 
that lists the known implemented and missing features of Rakudo 
and other Perl 6 implementations.

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are
many that we've missed.  Bug reports about missing and broken
features are welcomed at .

See http://perl6.org/ for links to much more information about 
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.
A draft of a Perl 6 book is available as  
in the release tarball.

The development team thanks all of the contributors and sponsors
for making Rakudo Star possible.  If you would like to contribute,
see , ask on the perl6-compi...@perl.org
mailing list, or join us on IRC #perl6 on freenode.

[0] https://github.com/rakudo/rakudo/blob/nom/docs/announce/2012.09
[1] http://github.com/rakudo/rakudo
[2] http://parrot.org/

Rakudo Star 2012.08 released

[Patrick R. Michaud]

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the August 2012 release of "Rakudo Star", a useful and
usable distribution of Perl 6.  The tarball for the August 2012
release is available from .
A Windows .MSI version of Rakudo Star is also being made available
in the downloads area.

In the Perl 6 world, we make a distinction between the language 
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  This Star release includes release 2012.08 [0] of the
Rakudo Perl 6 compiler [1], version 4.6 of the Parrot Virtual
Machine [2], and various modules, documentation, and other
resources collected from the Perl 6 community.

Some of the new features added to this release include:

* Rakudo Star now includes a Perl 6 debugger!  The debugger allows
  single-stepping, setting breakpoints, variable inspection/modification, 
  regex debugging, and more!  Enter "perl6-debug " to run 
  a script in debugging mode.  Enter "help" from a debug prompt to
  see the available commands.

* Memory usage of the build stage has been reduced by 35% - 40%.  This
  makes it possible to build and compile Rakudo Star on machines with
  less memory (although 1.2GB may still be needed for some 64-bit
  environments).

* Variables prefixed by | or \ in signatures are now sigilless, per updates
  to the Perl 6 specification.

* Circularities in module loading are now detected.

* An improved inliner, allowing a wider range of routines to be inlined.

* Str.bytes and lcfirst have been removed.  The tclc builtin
  has been added.

* 'abs' is now a normal subroutine instead of a prefix operator.

* IO::File and IO::Dir have been removed.

* The integer argument to IO::Socket.recv is now interpreted as 
  a number of characters/codepoints.

This release also contains a range of bug fixes, improvements to error
reporting and better failure modes. More exceptions are thrown as typed
exceptions, and more meta-model errors have been fixed to properly
report line numbers.

The following features have been deprecated or modified from previous
releases due to changes in the Perl 6 specification, and are being removed
or changed as follows:

* Parameters preceded by a | or \ can no longer have a sigil.

* IO::Path.dir (which returns the directory part of the path) has been
  renamed to IO::Path.directory.  IO::Path.dir will be removed or
  re-purposed.

* The Str.ucfirst builtin is deprecated; it will be replaced by Str.tc.

* The (experimental) LAZY statement prefix will soon be removed.

* Leading whitespace in rules and under :sigspace will no longer be
  converted to <.ws> .  For existing regexes that expect this conversion,
  add a  in front of leading whitespace to make it meta again.

* The ?-quantifier on captures in regexes currently binds the capture
  slot to a List containing either zero or one Match objects; i.e., it
  is equivalent to "** 0..1".  In the future, the ?-quantifier will
  bind the slot directly to a captured Match or to Nil.  Existing code
  can manage the transition by changing existing ?-quantifiers to
  use "** 0..1", which will continue to return a List of matches.

There are some key features of Perl 6 that Rakudo Star does not
yet handle appropriately, although they will appear in upcoming
releases.  Some of the not-quite-there features include:

  * macros
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * interactive readline that understands Unicode
  * non-blocking I/O
  * much of Synopsis 9

There is an online resource at http://perl6.org/compilers/features 
that lists the known implemented and missing features of Rakudo Star
2012.08 and other Perl 6 implementations.

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are
many that we've missed.  Bug reports about missing and broken
features are welcomed at .

See http://perl6.org/ for links to much more information about 
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.
A draft of a Perl 6 book is available as  
in the release tarball.

The development team thanks all of the contributors and sponsors
for making Rakudo Star possible.  If you would like to contribute,
see , ask on the perl6-compi...@perl.org
mailing list, or join us on IRC #perl6 on freenode.

[0] https://github.com/rakudo/rakudo/blob/nom/docs/announce/2012.08
[1] http://github.com/rakudo/rakudo
[2] http://parrot.org/

Re: The trouble with awesome

[Patrick R. Michaud]

On Sat, May 26, 2012 at 05:34:18AM +0530, Siddhant Saraf wrote:
> Rakud[o] is not _the_ reference implementation of Perl 6. Actually, there is
> no reference implementation for Perl 6. There never will be. Whoever wants
> to make a perl6 implementation is free to do so. Just follow the spec and
> you get to label your compiler as a Perl6 implementation. yay !

Just a very minor technical nit (to help preserve clarity):  Perl 6 is
anything that passes the test suite, which is not necessarily the 
same as the specification.  See Synopsis 1.

(Yes, this means the synopses can also contain bugs, and we can
and do file bug reports on the synopses themselves.)

Pm

Re: How to make a new operator.

[Patrick R. Michaud]

On Thu, Mar 22, 2012 at 11:07:08AM -0500, Bruce Gray wrote:
> Well, it works in Niecza. It does not (yet) work in Rakudo:
>   15:25  perl6: my @squares := 0, (-> *@a { @a.elems ** 2 })
> ... *; say ~@squares[^11];
>   15:25  ..niecza v15-4-g1f35f89: OUTPUT<<0 1 4 9 16 25 36 49
> 64 81 100NL>>
>   15:25  ..rakudo 1a468d: OUTPUT<<0 0 0 0 0 0 0 0 0 0 0NL>>

It now works in Rakudo, as of 2012.03-5-g69920db:

   > my @squares = 0, (-> *@a { @a.elems ** 2 }) ... *; say @squares[^11];
   0 1 4 9 16 25 36 49 64 81 100

Also @_ now DTRT again:

> my @squares = { @_ ** 2 } ... *;  say @squares[^11];
0 1 4 9 16 25 36 49 64 81 100

> my @triangle = 1, { @_[*-1] + @_ + 1 } ... *;  say @triangle[^11]
1 3 6 10 15 21 28 36 45 55 66

Note that Rakudo also doesn't require a binding operation for the array... 
assignment of detectably infinite lists (indicated here by the final 
Whatever term) is supported.

Pm

Re: How to make a new operator.

[Patrick R. Michaud]

On Fri, Mar 23, 2012 at 03:03:09PM +1300, Martin D Kealey wrote:
> On Thu, 22 Mar 2012, Carl Mäsak wrote:
> > Jonathan Lang (>>), Daniel (>):
> > >>    1, 2, 4 ... 100 # same as 1,2,4,8,16,32,64
> > >
> > > That last one doesn't work on Rakudo :-(
> >
> > And it never will. Note that 100 is not a power of 2, and that the goal
> > needs to match exactly. 
> 
> Hmmm, so it's likely that most times you get a Num rather than an Int or
> Rat, those won't stop either?
> 
>   1, 7 / 6.0 ... 2
>   1, sqrt(2), 2 ... 8

The expression 7/6.0 produces a Rat, so the first sequence properly 
stops at 2.

On Rakudo on my system, sqrt(2) indeed produces a Num,
but since floating point arithmetic doesn't result in
sqrt(2) / 1 == 2 / sqrt(2), no geometric sequence is deduced 
and the sequence fails with "unable to deduce sequence".

> Question: do we support
> 
>   1, 2i, -4 ... 256

I think this ought to work, but for some reason Rakudo on my system
hangs whenever I try it.  The following does work in Rakudo:

> say 1, { $^x * 2i } ... 256
1 0+2i -4+0i -0-8i 16+-0i 0+32i -64+0i -0-128i 256+-0i

The fact that the auto-deduced sequence hangs probably needs to be
filed as a bug report for Rakudo.

Pm

Re: [perl6/specs] a7cfe0: [S32] backtraces overhaul

[Patrick R. Michaud]

On Tue, Aug 23, 2011 at 05:36:27PM +0200, Damian Conway wrote:
> And I'd like there to be a more consistent approach than that
> (though I don't really care what it actually is).

+1 to consistency.

Pm

Re: Encapsulating the contents of container types

[Patrick R. Michaud]

On Mon, Aug 22, 2011 at 06:39:25AM +0100, Nicholas Clark wrote:
> Is it? If, at the implementation layer, all accesses to objects are actually
> function calls called via vtables, then surely it's *relatively* simple to
> change the vtable to replace
> 
> * mutator methods with methods which croak (the shallow read-only part)
> * accessor methods for internal storage with methods which return proxy
>   objects which are read-only

At present I don't think we have anything that identifies
mutator methods and/or accessor methods, so perhaps that's where
we would need to start.

Pm

Re: Encapsulating the contents of container types

[Patrick R. Michaud]

On Sat, Aug 20, 2011 at 04:41:08PM -0700, Darren Duncan wrote:
> I believe the general solution to this problem is to make all
> objects immutable, with the only exception being explicit
> references, and so mutating an object isn't an option; rather you
> have to derive a new object.
>
> "Values" of all types should be immutable, even if that type is
> Array or whatever, and only "Variables" should be mutable.
> ...

To make sure I understand correctly, you're essentially
saying that @a.push(3) should not modify @a directly -- someone
would have to write something like

 @a = @a.push(3)  # or @a .= push(3)

And to do a "shift", one would have to do something like
   ($value, @a) = @a;
since @a.shift would be unable to mutate the array.  (I'm not 
exactly sure what pop would look like.)

Is that correct?

Pm

Re: Close($file) required in Perl 6, unlike Perl 5

[Patrick R. Michaud]

On Mon, Jul 18, 2011 at 11:26:49AM -0400, Andrew Whitworth wrote:
> On Mon, Jul 18, 2011 at 10:41 AM, Peter Lobsinger  wrote:
> > The destructor does exactly that, but is not triggered by global teardown.
> 
> That seems wrong to me, we should be sweeping pools and destroying
> PMCs on global teardown. If we aren't doing that, it's a bug.

Now added as TT #2157, at least for the FileHandle not closing part.

Pm

Re: Close($file) required in Perl 6, unlike Perl 5

[Patrick R. Michaud]

On Mon, Jul 18, 2011 at 10:41:30AM -0400, Peter Lobsinger wrote:
> On Sun, Jul 17, 2011 at 11:00 AM, Patrick R. Michaud  
> wrote:
> > On Sun, Jul 17, 2011 at 10:21:19AM +0200, Moritz Lenz wrote:
> >>
> >> Question to the Parrot developers: How could I implement DESTROY methods
> >> in Rakudo? Is there any vtable I can override, or so? Note that such a
> >> method might itself allocate new GCables. While not urgent, it's
> >> important for us in the long run.
> >
> > A possibly related (and more relevant) question for Parrot devs:
> > is there any reason that FileHandle PMCs do not automatically
> > flush + close on destruction?
> 
> The destructor does exactly that, but is not triggered by global teardown.

To be a bit more direct, then:  Several of Parrot's target languages 
have the semantic that normal program exit will cause any open 
filehandles to be flushed and closed automatically.  How does a HLL
writer achieve this in Parrot?

Pm

Re: Bug?

[Patrick R. Michaud]

On Sun, Jul 17, 2011 at 10:40:01AM +0200, Moritz Lenz wrote:
> On 07/14/2011 11:47 PM, Parrot Raiser wrote:
> > When a subroutine is invoked with an empty parameter list, as follows:
> > 
> > run_stuff();
> > 
> > sub run_stuff {
> > my ($parm) = @_;
> > say "Parameter is $parm";
> > }
> > 
> > @_[0] contains "Any()".
> 
> Not "Any()", but Any (which say() prints as "Any()" to ease debugging)
> 
> > Should it?
> 
> Yes.

Not exactly -- master gets this wrong.  Type objects are supposed
to stringify to "" and produce a warning.

Nom (cf0da7d) also gets this somewhat wrong at present (but still better 
than master); it's treating the assignment as an item assignment.

Pm

Re: Close($file) required in Perl 6, unlike Perl 5

[Patrick R. Michaud]

On Sun, Jul 17, 2011 at 10:21:19AM +0200, Moritz Lenz wrote:
> 
> Question to the Parrot developers: How could I implement DESTROY methods
> in Rakudo? Is there any vtable I can override, or so? Note that such a
> method might itself allocate new GCables. While not urgent, it's
> important for us in the long run.

A possibly related (and more relevant) question for Parrot devs:
is there any reason that FileHandle PMCs do not automatically 
flush + close on destruction?

pmichaud@kiwi:~/nom$ cat fh.pir
.sub 'main' :main
$P0 = new ['FileHandle']
$P1 = $P0.'open'('test.txt', 'w')
$P1.'print'("Hello\n")
.end

pmichaud@kiwi:~/nom$ install/bin/parrot fh.pir
pmichaud@kiwi:~/nom$ cat test.txt
pmichaud@kiwi:~/nom$ ls -l test.txt
-rw-r--r-- 1 pmichaud pmichaud 0 2011-07-17 09:57 test.txt

Pm

Announce: Rakudo Star 2011.04 released

[Patrick R. Michaud]

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the April 2011 release of "Rakudo Star", a useful and usable
distribution of Perl 6.  The tarball for the April 2011 release is
available from .

Rakudo Star is aimed at "early adopters" of Perl 6.  We know that
it still has some bugs, it is far slower than it ought to be, and
there are some advanced pieces of the Perl 6 language specification
that aren't implemented yet.  But Rakudo Perl 6 in its current form
is also proving to be viable (and fun) for developing applications
and exploring a great new language.  These "Star" releases are
intended to make Perl 6 more widely available to programmers, grow
the Perl 6 codebase, and gain additional end-user feedback about the
Perl 6 language and Rakudo's implementation of it.

In the Perl 6 world, we make a distinction between the language 
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  The April 2011 Star release includes release #40
of the Rakudo Perl 6 compiler [1], version 3.3.0 of the Parrot 
Virtual Machine [2], and various modules, documentation,
and other resources collected from the Perl 6 community.

This release of Rakudo Star adds the following features over the
previous Star release:
  * Modules MiniDBI, form, HTTP::Daemon, Yaml and Module::Tools are
removed in this release. 
  * New modules Pies (including panda, the module installer) and 
HTTP::Server::Simple have been added.
  * New implementation of IO::Socket::INET, with basic IPv6 support
  * -p and -n command-line options are now available
  * Many new IO improvements, including stat-related methods
  * New --ll-backtrace command-line switch for printing PIR level stack traces
  * Preliminary implementation of Infix 'orelse'
  * Added Str.indent
  * Bugfixes to negation meta operator
  * Support for complex conjugation

There are some key features of Perl 6 that Rakudo Star does not
yet handle appropriately, although they will appear in upcoming
releases.  Some of the not-quite-there features include:
  * nested package definitions
  * binary objects, native types, pack and unpack
  * typed arrays
  * macros
  * state variables
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * pre and post constraints, and some other phasers
  * interactive readline that understands Unicode
  * backslash escapes in regex <[...]> character classes
  * non-blocking I/O
  * most of Synopsis 9
  * perl6doc or pod manipulation tools

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are
many that we've missed.  Bug reports about missing and broken
features are welcomed at .

See http://perl6.org/ for links to much more information about 
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.
An updated draft of a Perl 6 book is available as 
 in the release tarball.

The development team thanks all of the contributors and sponsors
for making Rakudo Star possible.  If you would like to contribute,
see , ask on the perl6-compi...@perl.org
mailing list, or join us on IRC #perl6 on freenode.

Rakudo Star releases are created on a three-month cycle, or as 
needed in response to important bug fixes or improvements.  
(The Rakudo compiler will continue with monthly releases.)  
The next planned release of Rakudo Star will be in July 2011.

[1] http://github.com/rakudo/rakudo
[2] http://parrot.org/

Re: Enumerating prefix operators, and spec changes

[Patrick R. Michaud]

On Wed, Mar 09, 2011 at 04:40:19PM -0800, Stefan O'Rear wrote:
> This is a more general problem: the distinction between prefix ops
> and functions is not well defined.  For instance, 'defined 1 && 0'
> is parsed as defined(1) && 0 by Rakudo, but as defined(1 && 0) by
> STD and derivatives.

I think STD tends to supercede the spec.

> Who has the authority to make changes to the spec like this, that
> would invalidate existing programs for the sake of a perceived
> improvement?  I would change this, and a few other things, but feel
> I lack this authority.  I wonder what the correct process is.

I believe the process is "Forgiveness is better than permission."  
In other words, change the spec, and if anyone carps we discuss
it then.  

Pm

Announce: Rakudo Star 2011.01 released

[Patrick R. Michaud]

(Resending, since I had the wrong date in the subject line of
my previous post.  Apologies to everyone for the duplicates! --Pm)

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the January 2011 release of "Rakudo Star", a useful and usable
distribution of Perl 6.  The tarball for the January 2011 release is
available from .

Starting with this January 2011 release, Rakudo Star releases will be
created on a three-month cycle, or as needed in response to important
bug fixes or improvements.  (The Rakudo compiler will continue with
monthly releases.)  The next planned release of Rakudo Star will be 
in April 2011.

Rakudo Star is aimed at "early adopters" of Perl 6.  We know that
it still has some bugs, it is far slower than it ought to be, and
there are some advanced pieces of the Perl 6 language specification
that aren't implemented yet.  But Rakudo Perl 6 in its current form
is also proving to be viable (and fun) for developing applications
and exploring a great new language.  These "Star" releases are
intended to make Perl 6 more widely available to programmers, grow
the Perl 6 codebase, and gain additional end-user feedback about the
Perl 6 language and Rakudo's implementation of it.

In the Perl 6 world, we make a distinction between the language 
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  The January 2011 Star release includes release #37
of the Rakudo Perl 6 compiler [1], version 3.0.0 of the Parrot 
Virtual Machine [2], and various modules, documentation,
and other resources collected from the Perl 6 community.

This release of Rakudo Star adds the following features over the
previous Star release:
  * faster subroutine calls (type cache)
  * implemented 'handles Rolename' trait
  * 'use Devel::Trace' debugging pragma
  * improved parsing of keyword boundaries
  * faster .comb

There are some key features of Perl 6 that Rakudo Star does not
yet handle appropriately, although they will appear in upcoming
releases.  Some of the not-quite-there features include:
  * nested package definitions
  * binary objects, native types, pack and unpack
  * typed arrays
  * macros
  * state variables
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * pre and post constraints, and some other phasers
  * interactive readline that understands Unicode
  * backslash escapes in regex <[...]> character classes
  * non-blocking I/O
  * most of Synopsis 9
  * perl6doc or pod manipulation tools

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are
many that we've missed.  Bug reports about missing and broken
features are welcomed at .

See http://perl6.org/ for links to much more information about 
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.
An updated draft of a Perl 6 book is available as 
 in the release tarball.

The development team thanks all of the contributors and sponsors
for making Rakudo Star possible.  If you would like to contribute,
see , ask on the perl6-compi...@perl.org
mailing list, or join us on IRC #perl6 on freenode.

[1] http://github.com/rakudo/rakudo
[2] http://parrot.org/

Announce: Rakudo Star 2010.12 released

[Patrick R. Michaud]

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the January 2011 release of "Rakudo Star", a useful and usable
distribution of Perl 6.  The tarball for the January 2011 release is
available from .

Starting with this January 2011 release, Rakudo Star releases will be
created on a three-month cycle, or as needed in response to important
bug fixes or improvements.  (The Rakudo compiler will continue with
monthly releases.)  The next planned release of Rakudo Star will be 
in April 2011.

Rakudo Star is aimed at "early adopters" of Perl 6.  We know that
it still has some bugs, it is far slower than it ought to be, and
there are some advanced pieces of the Perl 6 language specification
that aren't implemented yet.  But Rakudo Perl 6 in its current form
is also proving to be viable (and fun) for developing applications
and exploring a great new language.  These "Star" releases are
intended to make Perl 6 more widely available to programmers, grow
the Perl 6 codebase, and gain additional end-user feedback about the
Perl 6 language and Rakudo's implementation of it.

In the Perl 6 world, we make a distinction between the language 
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  The January 2011 Star release includes release #37
of the Rakudo Perl 6 compiler [1], version 3.0.0 of the Parrot 
Virtual Machine [2], and various modules, documentation,
and other resources collected from the Perl 6 community.

This release of Rakudo Star adds the following features over the
previous Star release:
  * faster subroutine calls (type cache)
  * implemented 'handles Rolename' trait
  * 'use Devel::Trace' debugging pragma
  * improved parsing of keyword boundaries
  * faster .comb

There are some key features of Perl 6 that Rakudo Star does not
yet handle appropriately, although they will appear in upcoming
releases.  Some of the not-quite-there features include:
  * nested package definitions
  * binary objects, native types, pack and unpack
  * typed arrays
  * macros
  * state variables
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * pre and post constraints, and some other phasers
  * interactive readline that understands Unicode
  * backslash escapes in regex <[...]> character classes
  * non-blocking I/O
  * most of Synopsis 9
  * perl6doc or pod manipulation tools

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are
many that we've missed.  Bug reports about missing and broken
features are welcomed at .

See http://perl6.org/ for links to much more information about 
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.
An updated draft of a Perl 6 book is available as 
 in the release tarball.

The development team thanks all of the contributors and sponsors
for making Rakudo Star possible.  If you would like to contribute,
see , ask on the perl6-compi...@perl.org
mailing list, or join us on IRC #perl6 on freenode.

[1] http://github.com/rakudo/rakudo
[2] http://parrot.org/

Announce: Rakudo Star 2010.12 released

[Patrick R. Michaud]

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the December 2010 release of "Rakudo Star", a useful and usable
distribution of Perl 6.  The tarball for the December 2010 release is
available from .

Rakudo Star is aimed at "early adopters" of Perl 6.  We know that
it still has some bugs, it is far slower than it ought to be, and
there are some advanced pieces of the Perl 6 language specification
that aren't implemented yet.  But Rakudo Perl 6 in its current form
is also proving to be viable (and fun) for developing applications
and exploring a great new language.  These "Star" releases are
intended to make Perl 6 more widely available to programmers, grow
the Perl 6 codebase, and gain additional end-user feedback about the
Perl 6 language and Rakudo's implementation of it.

In the Perl 6 world, we make a distinction between the language 
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  The December 2010 Star release includes release #36
of the Rakudo Perl 6 compiler [1], version 2.11.0 of the Parrot 
Virtual Machine [2], and various modules, documentation,
and other resources collected from the Perl 6 community.

This release of Rakudo Star adds the following features over the
previous Star release:
  * New .trans algorithm
  * Configuration improvements
  * More bug fixes

There are some key features of Perl 6 that Rakudo Star does not
yet handle appropriately, although they will appear in upcoming
releases.  Thus, we do not consider Rakudo Star to be a
"Perl 6.0.0" or "1.0" release.  Some of the not-quite-there
features include:
  * nested package definitions
  * binary objects, native types, pack and unpack
  * typed arrays
  * macros
  * state variables
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * pre and post constraints, and some other phasers
  * interactive readline that understands Unicode
  * backslash escapes in regex <[...]> character classes
  * non-blocking I/O
  * most of Synopsis 9
  * perl6doc or pod manipulation tools

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are
many that we've missed.  Bug reports about missing and broken
features are welcomed at .

See http://perl6.org/ for links to much more information about 
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.
An updated draft of a Perl 6 book is available as 
 in the release tarball.

The development team thanks all of the contributors and sponsors
for making Rakudo Star possible.  If you would like to contribute,
see , ask on the perl6-compi...@perl.org
mailing list, or join us on IRC #perl6 on freenode.

Starting with the January 2011 release, Rakudo Star releases will be
created on a three-month cycle, or as needed in response to important
bug fixes or improvements.  The next planned release of Rakudo Star
will be on January 25, 2011.

[1] http://github.com/rakudo/rakudo
[2] http://parrot.org/

Announce: Rakudo Star 2010.11 released

[Patrick R. Michaud]

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the November 2010 release of "Rakudo Star", a useful and usable
distribution of Perl 6.  The tarball for the November 2010 release is
available from .

Rakudo Star is aimed at "early adopters" of Perl 6.  We know that
it still has some bugs, it is far slower than it ought to be, and
there are some advanced pieces of the Perl 6 language specification
that aren't implemented yet.  But Rakudo Perl 6 in its current form
is also proving to be viable (and fun) for developing applications
and exploring a great new language.  These "Star" releases are
intended to make Perl 6 more widely available to programmers, grow
the Perl 6 codebase, and gain additional end-user feedback about the
Perl 6 language and Rakudo's implementation of it.

In the Perl 6 world, we make a distinction between the language 
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  The November 2010 Star release includes release #35
of the Rakudo Perl 6 compiler [1], version 2.10.1 of the Parrot 
Virtual Machine [2], and various modules, documentation,
and other resources collected from the Perl 6 community.

This release of Rakudo Star adds the following features over the
previous Star release:
  * qw// is implemented
  * The .trans method is 5x faster
  * Indexing with ranges and Whatever offsets now works

There are some key features of Perl 6 that Rakudo Star does not
yet handle appropriately, although they will appear in upcoming
releases.  Thus, we do not consider Rakudo Star to be a
"Perl 6.0.0" or "1.0" release.  Some of the not-quite-there
features include:
  * nested package definitions
  * binary objects, native types, pack and unpack
  * typed arrays
  * macros
  * state variables
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * pre and post constraints, and some other phasers
  * interactive readline that understands Unicode
  * backslash escapes in regex <[...]> character classes
  * non-blocking I/O
  * most of Synopsis 9
  * perl6doc or pod manipulation tools

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are
many that we've missed.  Bug reports about missing and broken
features are welcomed at .

See http://perl6.org/ for links to much more information about 
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.
An updated draft of a Perl 6 book is available as 
 in the release tarball.

The development team thanks all of the contributors and sponsors
for making Rakudo Star possible.  If you would like to contribute,
see , ask on the perl6-compi...@perl.org
mailing list, or join us on IRC #perl6 on freenode.

Rakudo Star releases are created on a monthly cycle or as needed
in response to important bug fixes or improvements.  The next planned 
release of Rakudo Star will be on December 28, 2010.

[1] http://github.com/rakudo/rakudo
[2] http://parrot.org/

Re: IO Multiplexing

[Patrick R. Michaud]

On Fri, Nov 12, 2010 at 11:21:10AM -0800, Stefan O'Rear wrote:
> TIMTOWDI.  Perl without system calls is not Perl.

+1

> This is why S16 is junk - too much blue-sky thinking, not enough
> pragmatism and practical experience.

Agreed.

> Forbidding things out of idealistic concerns like API purity is not
> the Perl way.

+1

Pm

Re: Unicode Categories

[Patrick R. Michaud]

On Wed, Nov 10, 2010 at 01:21:57PM -0500, Chase Albert wrote:
> That's exactly what I was looking for*. Awesome, thank you.
> 
> * Almost. E.g. isL would be nice to have as well.

Those exist also:

  $ ./perl6
  > say 'abCD34' ~~ /  /
  a
  > say 'abCD34' ~~ /  /
  3
  > 

Pm

Re: Unicode Categories

[Patrick R. Michaud]

On Wed, Nov 10, 2010 at 01:03:26PM -0500, Chase Albert wrote:
> Sorry if this is the wrong forum. I was wondering if there was a way to
> specify unicode
> categoriesin
> a regular expression (and hence a grammar), or if there would be any
> consideration for adding support for that (requiring some kind of special
> syntax).

Unicode categories are done using assertion syntax with "is" followed by
the category name.  Thus  (uppercase letter),  (decimal digit), 
 (space separator), etc.

This even works in Rakudo today:

$ ./perl6
> say 'abcdEFG' ~~ /  /
E

They can also be combined, as in +isLu+isLt  (uppercase+titlecase).
The relevant section of the spec is in Synopsis 5; search for "Unicode
properties are always available with a prefix".

Hope this helps!

Pm

Announce: Rakudo Star 2010.10 released

[Patrick R. Michaud]

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the October 2010 release of "Rakudo Star", a useful and usable
distribution of Perl 6.  The tarball for the October 2010 release is
available from .

Rakudo Star is aimed at "early adopters" of Perl 6.  We know that
it still has some bugs, it is far slower than it ought to be, and
there are some advanced pieces of the Perl 6 language specification
that aren't implemented yet.  But Rakudo Perl 6 in its current form
is also proving to be viable (and fun) for developing applications
and exploring a great new language.  These "Star" releases are
intended to make Perl 6 more widely available to programmers, grow
the Perl 6 codebase, and gain additional end-user feedback about the
Perl 6 language and Rakudo's implementation of it.

In the Perl 6 world, we make a distinction between the language 
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  The October 2010 Star release includes release #34
of the Rakudo Perl 6 compiler [1], version 2.9.0 of the Parrot 
Virtual Machine [2], and various modules, documentation,
and other resources collected from the Perl 6 community.

This release of Rakudo Star adds the following features over the
previous Star release:
  * A simple implementation of 'require'
  * Local timezone is available in $*TZ
  * Implementations of ms// ss/// (samespace)
  * Speed improvements to Str.flip
  * Hyperoperator versions of +=
  * Improved diagnostic messages and warning messages
  * True and False now stringify properly
  * Attribute modification via introspection

There are some key features of Perl 6 that Rakudo Star does not
yet handle appropriately, although they will appear in upcoming
releases.  Thus, we do not consider Rakudo Star to be a
"Perl 6.0.0" or "1.0" release.  Some of the not-quite-there
features include:
  * nested package definitions
  * binary objects, native types, pack and unpack
  * typed arrays
  * macros
  * state variables
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * pre and post constraints, and some other phasers
  * interactive readline that understands Unicode
  * backslash escapes in regex <[...]> character classes
  * non-blocking I/O
  * most of Synopsis 9
  * perl6doc or pod manipulation tools

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are
many that we've missed.  Bug reports about missing and broken
features are welcomed at .

See http://perl6.org/ for links to much more information about 
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.
An updated draft of a Perl 6 book is available as 
 in the release tarball.

The development team thanks all of the contributors and sponsors
for making Rakudo Star possible.  If you would like to contribute,
see , ask on the perl6-compi...@perl.org
mailing list, or join us on IRC #perl6 on freenode.

Rakudo Star releases are created on a monthly cycle or as needed
in response to important bug fixes or improvements.  The next planned 
release of Rakudo Star will be on November 23, 2010.

[1] http://github.com/rakudo/rakudo
[2] http://parrot.org/
[3] http://github.com/perl6/roast

Re: threads?

[Patrick R. Michaud]

On Tue, Oct 12, 2010 at 07:22:33AM -0700, Damian Conway wrote:
> What we really need is some anecdotal evidence from folks who are actually
> using threading in real-world situations (in *any* languages). What has worked
> in practice? What has worked well? What was painful? What was error-prone?
> And for which kinds of tasks?
> 
> And we also need to stand back a little further and ask: is "threading"
> the right approach at all? Do threads work in *any* language? Are there
> better metaphors?
> [...]

I agree fully with Damian.  At YAPC::EU in Pisa, I proposed that
since questions of threading and concurrency in Perl 6 (and Parrot)
seem to be eternally asked and unanswered questions, that we probably 
need to start pushing on the answer at least a little bit, if only to
have some implementation-level issues to frame discussion and
help illustrate the overall outlines of an answer a bit better.

My guess is that the overall question of threading and concurrency may 
be too large/vague to be attacked at once, so let's break it down into 
smaller, real-world use cases and see if we can find some patterns 
from those.  In Rakudo's case, my plan is to focus on developing 
some sort of concurrent implementation of the Perl 6 hyperoperators 
(which ATM is one of Perl 6's most natural expressions of concurrency).

Once we have a basic concurrent hyperoperator implementation -- even
if it's not a particularly good one, we'll have a lot better
understanding of the issues.  We can better understand how
concurrency might be expressed in other parts of the language,
and we can provide Parrot and other underlying runtimes with
real examples of the kind of concurrency primitives we'd like to
have available.

Then, with a few more examples in hand, I think we can start to
get at some answers as to what a "Perl concurrency" solution
will look like.

[N.B.:  This is very similar to what has happened in other parts
of Perl 6, such as regular expressions and grammars.  We didn't
get a good feel for what was needed until we actually went through
the exercise of building a few Perl 6 standard grammars/parsers in 
Perl 6.]

Pm

Announce: Rakudo Star 2010.09 released

[Patrick R. Michaud]

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the September 2010 release of "Rakudo Star", a useful and usable
distribution of Perl 6.  The tarball for the September 2010 release is
available from .

Rakudo Star is aimed at "early adopters" of Perl 6.  We know that
it still has some bugs, it is far slower than it ought to be, and
there are some advanced pieces of the Perl 6 language specification
that aren't implemented yet.  But Rakudo Perl 6 in its current form
is also proving to be viable (and fun) for developing applications
and exploring a great new language.  These "Star" releases are
intended to make Perl 6 more widely available to programmers, grow
the Perl 6 codebase, and gain additional end-user feedback about the
Perl 6 language and Rakudo's implementation of it.

In the Perl 6 world, we make a distinction between the language 
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  The September 2010 Star release includes release #33
of the Rakudo Perl 6 compiler [1], version 2.8.0 of the Parrot 
Virtual Machine [2], and various modules, documentation,
and other resources collected from the Perl 6 community.

This release of Rakudo Star adds the following features over the
previous Star release:
  * Several performance improvements have been implemented;
notably in the slurp() and reverse() functions
  * The series operator has been refactored and updated to the current 
specification
  * Temporal objects (DateTime, Date, Instant, and Duration) are now 
completely implemented
  * Enumeration objects now conform much closer to the specification
  * 'now' and 'time' are now terms instead of functions.  This means
you can write 'time - 1' and it will do what you mean, but
   'time()' is no longer valid.
  * The Perl 6 specification tests [3] are now included in the distribution.

There are some key features of Perl 6 that Rakudo Star does not
yet handle appropriately, although they will appear in upcoming
releases.  Thus, we do not consider Rakudo Star to be a
"Perl 6.0.0" or "1.0" release.  Some of the not-quite-there
features include:
  * nested package definitions
  * binary objects, native types, pack and unpack
  * typed arrays
  * macros
  * state variables
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * pre and post constraints, and some other phasers
  * interactive readline that understands Unicode
  * backslash escapes in regex <[...]> character classes
  * non-blocking I/O
  * most of Synopsis 9
  * perl6doc or pod manipulation tools

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are
many that we've missed.  Bug reports about missing and broken
features are welcomed.

See http://perl6.org/ for links to much more information about 
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.
An updated draft of a Perl 6 book is available as 
 in the release tarball.

The development team thanks all of the contributors and sponsors
for making Rakudo Star possible.  If you would like to contribute,
see , ask on the perl6-compi...@perl.org
mailing list, or join us on IRC #perl6 on freenode.

Rakudo Star releases are created on a monthly cycle or as needed
in response to important bug fixes or improvements.  The next planned 
release of Rakudo Star will be on October 26, 2010.

[1] http://github.com/rakudo/rakudo
[2] http://parrot.org/
[3] http://github.com/perl6/roast

Re: [perl6/specs] 761178: remove some some duplicate words words

[Patrick R. Michaud]

On Wed, Sep 08, 2010 at 04:02:10PM +0400, Richard Hainsworth wrote:
> I do want the diffs back: its the only way I have to keep at least
> some idea of what is changing any why.

We know that a lot of people would like to see the diffs available
through the commit messages, but afaik none of us actively maintaining
the github archive quite know how to make that happen.  Something
beyond "please bring diffs back" would be very helpful to us here.

For those who prefer to just have links to the diffs without the
text of the diffs, subscribing to the commit RSS feed is probably 
the best bet.

Pm

Announce: Rakudo Star 2010.08 released

[Patrick R. Michaud]

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the August 2010 release of "Rakudo Star", a useful and usable
distribution of Perl 6.  The tarball for the August 2010 release is
available from .

Rakudo Star is aimed at "early adopters" of Perl 6.  We know that
it still has some bugs, it is far slower than it ought to be, and
there are some advanced pieces of the Perl 6 language specification
that aren't implemented yet.  But Rakudo Perl 6 in its current form
is also proving to be viable (and fun) for developing applications
and exploring a great new language.  These "Star" releases are
intended to make Perl 6 more widely available to programmers, grow
the Perl 6 codebase, and gain additional end-user feedback about the
Perl 6 language and Rakudo's implementation of it.

In the Perl 6 world, we make a distinction between the language 
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  The August 2010 Star release includes release #32
of the Rakudo Perl 6 compiler [1], version 2.7.0 of the Parrot 
Virtual Machine [2], and various modules, documentation,
and other resources collected from the Perl 6 community.

This release of Rakudo Star adds the following features over the
previous Star release:
  * Nil is now undefined
  * Many regex modifiers are now recognized on the outside of regexes
  * Mathematic and range operations are now faster (they're still slow,
but they're significantly faster than they were in the previous release)
  * Initial implementations of .pack and .unpack
  * MAIN can parse short arguments
  * Removed a significant memory leak for loops and other repeated blocks

This release (temporarily?) omits the Config::INI module that was
included in the 2010.07 release, as it no longer builds with the 
shipped version of Rakudo.  We hope to see Config::INI return soon.

There are some key features of Perl 6 that Rakudo Star does not
yet handle appropriately, although they will appear in upcoming
releases.  Thus, we do not consider Rakudo Star to be a
"Perl 6.0.0" or "1.0" release.  Some of the not-quite-there
features include:
  * nested package definitions
  * binary objects, native types, pack and unpack
  * typed arrays
  * macros
  * state variables
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * pre and post constraints, and some other phasers
  * interactive readline that understands Unicode
  * backslash escapes in regex <[...]> character classes
  * non-blocking I/O
  * most of Synopsis 9
  * perl6doc or pod manipulation tools

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are
many that we've missed.  Bug reports about missing and broken
features are welcomed.

See http://perl6.org/ for links to much more information about 
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.
An updated draft of a Perl 6 book is available as 
 in the release tarball.

The development team thanks all of the contributors and sponsors
for making Rakudo Star possible.  If you would like to contribute,
see , ask on the perl6-compi...@perl.org
mailing list, or join us on IRC #perl6 on freenode.

Rakudo Star releases are created on a monthly cycle or as needed
in response to important bug fixes or improvements.  The next planned 
release of Rakudo Star will be on September 28, 2010.

[1] http://github.com/rakudo/rakudo
[2] http://parrot.org/

Re: pattern alternation (was Re: How are ...)

[Patrick R. Michaud]

On Thu, Aug 05, 2010 at 10:27:50AM -0400, Aaron Sherman wrote:
> On Thu, Aug 5, 2010 at 7:55 AM, Carl Mäsak  wrote:
> > I see this particular thinko a lot, though. Maybe some Perl 6 lint
> > tool or another will detect when you have a regex containing ^ at its
> > start, $ at the end, | somewhere in the middle, and no [] to
> > disambiguate.
> 
> You know, this problem would go away, almost entirely, if we had a :f[ull]
> adverb for regex matching that imposed ^[...]$ around the entire match. Then
> your code becomes:
> 
>   m:f/<[A..Z]>+|<[a..z]>+/

There's a version of this already.  Matching against an explicit 'regex', 
'token', or 'rule' automatically anchors it on both ends.  Thus:

$string ~~ regex { <[A..Z]>+ | <[a..z]>+ }

is equivalent to

$string ~~ regex { ^ [ + | <[a..z]>+ ] $ }

Pm

Re: pattern alternation (was Re: How are ...)

[Patrick R. Michaud]

On Thu, Aug 05, 2010 at 12:29:38AM -0700, Darren Duncan wrote:
> Carl Mäsak wrote:
> >Darren (>):
> >>Read what I said again.  I was proposing that the namespace comprised of
> >>names matching a pattern like this:
> >>
> >> /^ <[A..Z]>+ | <[a..z]>+ $/
> >
> >/^ [<[A..Z]>+ | <[a..z]>+] $/
> 
> Are the square brackets necessary when the pattern doesn't contain
> anything other than the alternatives?

In this case yes -- the original pattern without the square brackets
would act like:

/ [^ <[A..Z]>+] | [<[a..z]>+ $] /

In other words, the original pattern says "starting with uppercase
or ending with lowercase".

Pm

Re: Smart match isn't on Bool

[Patrick R. Michaud]

On Sat, Jul 31, 2010 at 04:29:00PM -0400, Aaron Sherman wrote:
> My problem with that is that it's a really odd use of given/when, and given
> the implicit smart-match, it doesn't make much sense. Now, to slightly
> backtrack, I do agree that there should be at least one way to do something,
> and if that were the only way to perform independent tests within a given,
> I'd agree. Thankfully, it's not:
> 
>  given $_ {
>when /clock/ { say "clock" }
>if time > $limit { say "tick" }
>default { say "tock" }
>  }

The problem with this formulation is that a successful 'when'
exits the block, while a successful 'if' does not.  This is one
of the significant differences between 'if' and 'when'.

So in the above, the default say "tock"  is executed regardless
of the result of the time > $limit test.

> Well, since it's easy to do both, as demonstrated above, I think we can
> agree that we've satisfied the first rule.

It's not as easy to do both as your example seems to illustrate.
Perhaps you can provide a better example that does illustrate
testing for a condition that also results in exiting the C 
block?

Pm

Re: Smart match isn't on Bool

[Patrick R. Michaud]

On Sat, Jul 31, 2010 at 10:56:47AM -0600, David Green wrote:
> It's not unreasonable, especially if that's what you expect.  
> But it's even more reasonable to expect this to work:
>   given $something { 
>   when True { say "That's the truth!" }
>   when 42 { say "Good answer!" }
>   when "viaduct" { say "You guessed the secret word!" }
>   }

I'm not so sure about this.  There's an argument to be made that
the C and C cases should never be reachable,
since both C<42> and C<"viaduct"> are considered "true" values...

... unless you want C to do a value-and-type check,
in which case it doesn't exactly follow the pattern for smartmatching
of the other builtin types (which only check value equivalence, 
not type equivalence).  

Pm

Re: Smart match isn't on Bool

[Patrick R. Michaud]

On Sat, Jul 31, 2010 at 11:47:13AM -0400, Brandon S Allbery KF8NH wrote:
> [...], and
> if the point is to be a general case statement then "when  "
> should smartmatch  against $_ instead of evaluating it with $_
> available as a shorthand/topic.  

This is exactly what "when  block" does -- it smartmatches
 against $_.  The problem is that there are at least two 
interpretations of a true result of :

when True { ... }# execute when $_ is exactly "True"

when foo() { ... }   # execute when foo() returns true

It's been decided that the latter is far more useful in general;
there are plenty of ways to express the former that are much
less ambiguous.

Pm

Re: Array membership test?

[Patrick R. Michaud]

On Fri, Jul 30, 2010 at 01:52:18AM +0200, Jonathan Worthington wrote:
> Mark J. Reed wrote:
> >Possibly a FAQ, but is there a simple way of asking if an item is
> >contained in an array?  
> 
> > my @x = 1,2,3; say ?...@x.grep(2); say ?...@x.grep(4);
> 1
> 0
> 
> Though more efficient would be:
> 
> > my @x = 1,2,3; say ?...@x.first(2); say ?...@x.first(4);
> 1
> 0

If .grep and List.Bool are implemented the way I think they should
be (and the way they are in Rakudo), then both of the above are 
equally efficient.  :-)

Pm

Rakudo Star - a useful, usable, "early adopter" distribution of Perl 6

[Patrick R. Michaud]

On behalf of the Rakudo and Perl 6 development teams, I'm happy to
announce the July 2010 release of "Rakudo Star", a useful and usable
distribution of Perl 6.  The tarball for the July 2010 release is
available from .

Rakudo Star is aimed at "early adopters" of Perl 6.  We know that
it still has some bugs, it is far slower than it ought to be, and
there are some advanced pieces of the Perl 6 language specification
that aren't implemented yet.  But Rakudo Perl 6 in its current form
is also proving to be viable (and fun) for developing applications
and exploring a great new language.  These "Star" releases are
intended to make Perl 6 more widely available to programmers, grow
the Perl 6 codebase, and gain additional end-user feedback about the
Perl 6 language and Rakudo's implementation of it.

In the Perl 6 world, we make a distinction between the language 
("Perl 6") and specific implementations of the language such as
"Rakudo Perl".  "Rakudo Star" is a distribution that includes
release #31 of the Rakudo Perl 6 compiler [1], version 2.6.0 of
the Parrot Virtual Machine [2], and various modules, documentation,
and other resources collected from the Perl 6 community.  We
plan to make Rakudo Star releases on a monthly schedule, with
occasional special releases in response to important bugfixes or
changes.

Some of the many cool Perl 6 features that are available in this
release of Rakudo Star:
  * Perl 6 grammars and regexes
  * formal parameter lists and signatures
  * metaoperators
  * gradual typing
  * a powerful object model, including roles and classes
  * lazy list evaluation
  * multiple dispatch
  * smart matching
  * junctions and autothreading
  * operator overloading (limited forms for now)
  * introspection
  * currying
  * a rich library of builtin operators, functions, and types
  * an interactive read-evaluation-print loop
  * Unicode at the codepoint level
  * resumable exceptions

There are some key features of Perl 6 that Rakudo Star does not
yet handle appropriately, although they will appear in upcoming
releases.  Thus, we do not consider Rakudo Star to be a
"Perl 6.0.0" or "1.0" release.  Some of the not-quite-there
features include:
  * nested package definitions
  * binary objects, native types, pack and unpack
  * typed arrays
  * macros
  * state variables
  * threads and concurrency
  * Unicode strings at levels other than codepoints
  * pre and post constraints, and some other phasers
  * interactive readline that understands Unicode
  * backslash escapes in regex <[...]> character classes
  * non-blocking I/O
  * most of Synopsis 9
  * perl6doc or pod manipulation tools

In many places we've tried to make Rakudo smart enough to inform the
programmer that a given feature isn't implemented, but there are
many that we've missed.  Bug reports about missing and broken
features are welcomed.

See http://perl6.org/ for links to much more information about 
Perl 6, including documentation, example code, tutorials, reference
materials, specification documents, and other supporting resources.

Rakudo Star also bundles a number of modules; a partial list of
the modules provided by this release include:
  * Blizkost
  - enables some Perl 5 modules to be used from within Rakudo Perl 6
  * MiniDBI
  - a simple database interface for Rakudo Perl 6
  * Zavolaj
  - call C library functions from Rakudo Perl 6
  * SVG and SVG::Plot
  - create scalable vector graphics
  * HTTP::Daemon
  - a simple HTTP server
  * XML::Writer
  - generate XML
  * YAML
  - dump Perl 6 objects as YAML
  * Term::ANSIColor
  - color screen output using ANSI escape sequences
  * Test::Mock
  - create mock objects and check what methods were called
  * Math::Model
  - describe and run mathematical models
  * Config::INI
  - parse and write configuration files
  * File::Find
  - find files in a given directory
  * LWP::Simple
  - fetch resources from the web

These are not considered "core Perl 6 modules", and as module
development for Perl 6 continues to mature, future releases
of Rakudo Star will likely come bundled with a different set
of modules. Deprecation policies for bundled modules will be
created over time, and other Perl 6 distributions may choose
different sets of modules or policies.  More information about
Perl 6 modules can be found at http://modules.perl6.org/.

Rakudo Star also contains a draft of a Perl 6 book -- see 
 in the release tarball.

The development team thanks all of the contributors and sponsors
for making Rakudo Star possible.  If you would like to contribute,
see , ask on the perl6-compi...@perl.org
mailing list, or join us on IRC #perl6 on freenode.

Rakudo Star releases are created on a monthly cycle or as needed
in response to important bug fixes or improvements.  The next planned 
release of Rakudo Star will be on August 24, 2010.

[1] http://github.com/rakudo/rakud

Rakudo 'ng' branch is now 'master'

[Patrick R. Michaud]

I've just completed the rename of the 'ng' branch to become the
new 'master' branch.  The old 'master' branch is now called 'alpha'.

If you have an existing checkout (clone) of the Rakudo repository,
it's probably a good idea to get a new fresh clone rather than trying
to pull updates from the existing repo.

We know that the new 'master' still doesn't pass a lot of tests
but we expect that to change soon.  People who want to continue
using the older-and-more-complete Rakudo should either use the
new 'alpha' branch or the 2010-01 ("Minneapolis") release.

Thanks!

Pm

Re: Gripes about Pod6 (S26)

[Patrick R. Michaud]

On Fri, Feb 05, 2010 at 03:43:04PM -0500, Austin Hastings wrote:
> Second, POD is not XML, and it definitely isn't DOCBOOK. Why do I
> need magic reserved words like TOC and APPENDIX? I'm not writing a
> book, I'm writing code. And if I was writing a book, I wouldn't be
> dumb enough to write it in POD. 

Actually, it's worth noting that (a slightly modified version of)
Perl 5 POD has indeed been used to write several substantial
books.  I'd be very sad if (Perl 6) POD couldn't be easily used 
or converted into something that can be used to generate manual 
pages and reference documentation.

Pm

Re: One-pass parsing and forward type references

[Patrick R. Michaud]

On Mon, Feb 01, 2010 at 05:56:09PM +0100, Jan Ingvoldstad wrote:
> On Mon, Feb 1, 2010 at 17:46, Patrick R. Michaud  wrote:
> > There's a third way:
> >
> >class B { ... }# introduce B as a class name without definition
> > class A { sub foo { B::bar } }
> >
> >class B { sub bar { A::foo } }
> 
> It seems to me that this doesn't really solve the problems that will occur
> when people start making packages independently of eachother.
> 
> Of course it can be solved by submitting patches to the other developer's
> code, but it seems inelegant.

I see it as not being much different that what already happens now
in most languages I deal with.

Assume the above lines of code are in different files -- one for A
and one for B.  Presumably A has a reason for saying "class B { ... }"  
instead of the more likely "use B;" -- i.e., the author of A knows 
that it is using B, and that B is likely to refer back to A.

And in the above example, I'd expect the file containing the definition
of B to likewise have either a "use A;" or "class A { ... }"
declaration.

It ultimately comes down to the fact that Perl expects each module
to declare class names before they get used, unless the class
names are part of CORE.

Pm

Re: One-pass parsing and forward type references

[Patrick R. Michaud]

On Mon, Feb 01, 2010 at 05:55:47PM +0100, Carl Mäsak wrote:
> Is it allowed to do 'class B { ... }' several times in different files
> before finally declaring the real B? If so, then I'd consider it
> equivalent to my proposed keyword, and thus there'd be no need for the
> latter.

Yes.  And "declaring the real B" doesn't have to be "final", nor
does it have to occur at all (as long as none of the features needed
from B are ever needed).

Pm

Announce: Rakudo Perl 6 Development Release #25 ("Minneapolis")

[Patrick R. Michaud]

[This notice is going out a bit late; the release was indeed
produced on time, but I was delayed in sending out this notice.
With apologies for the delay...  --Pm]

On behalf of the Rakudo development team, I'm pleased to announce the
January 2010 development release of Rakudo Perl #25 "Minneapolis".
Rakudo is an implementation of Perl 6 on the Parrot Virtual Machine
(see http://www.parrot.org).  The tarball for the January 2010 release
is available from http://github.com/rakudo/rakudo/downloads .

Rakudo Perl follows a monthly release cycle, with each release 
code named after a Perl Mongers group.  The January 2010 release 
is code named "Minneapolis" for Minneapolis.pm, hosts of the annual 
Frozen Perl Workshop [1].  In 2009 the Frozen Perl Workshop featured a 
one-day hackathon for Perl 6 and Rakudo development, which ultimately 
informed the design and implementation of the current build system.
(The 2010 Frozen Perl Workshop will be on February 6, 2010, for those
interested in attending.)

Shortly after the October 2009 (#22) release, the Rakudo team began a new
branch of Rakudo development ("ng") that refactors the grammar to much more
closely align with STD.pm as well as update some core features that have been
difficult to achieve in the master branch [2, 3].  We had planned for
this release to be created from the new branch, but holiday vacations
and other factors conspired against us.  This is absolutely the final 
release from the old development branch; we expect to make the new branch 
the official "master" branch shortly after this release.

This release of Rakudo requires Parrot 2.0.0.  One must still
perform "make install" in the Rakudo directory before the "perl6"
executable will run anywhere other than the Rakudo build directory.
For the latest information on building and using Rakudo Perl, see the
README file section titled "Building and invoking Rakudo".

Some of the specific changes and improvements occuring with this
release include:

* Rakudo is now passing 31,957 spectests, or 85.7% of the available
  test suite.  This is roughly the same level as the December 2009
  release (because most effort has taken place in the "ng" branch
  as described above).

* Rakudo's calling conventions have been updated to match changes
  in Parrot 2.0.0's calling and context structures.

The Perl 6 language specification is still in flux. Please take note of the
following changes, which might affect your existing programs. In the next
release of Rakudo, the deprecated features will likely be gone.

* The root of the object hierarchy has been changed from 'Object' to 'Mu'.
  The type 'Object' goes away.

* The term 'undef' is gone. You can replace it with other constructs,
  depending on context:
- 'Nil' is undefined in item context, and the empty list in list context
- 'Mu' is the most general undefined value which does not flatten in list
  context
- as a smart matching target, you can replace '$obj ~~ undef'
  by '$obj ~~ *.notdef'

* Builtin classes will derive from 'Cool' (which itself derives from 'Any').
  Most of the builtin methods on these classes will be defined in the
  'Cool' class instead of 'Any'.  See Synopsis 2 for more details.

* Starting with the next release, we will likely switch to using
  ".MM" instead of "-MM" (dot instead of hyphen) as release 
  identifiers.  This is intended to simplify building and packaging
  for other distribution systems.

The development team thanks all of our contributors and sponsors for
making Rakudo Perl possible.  If you would like to contribute,
see http://rakudo.org/how-to-help , ask on the perl6-compi...@perl.org
mailing list, or ask on IRC #perl6 on freenode.

The next release of Rakudo (#26) is scheduled for February 18, 2010.
A list of the other planned release dates and codenames for 2010 is
available in the "docs/release_guide.pod" file.  In general, Rakudo
development releases are scheduled to occur two days after each
Parrot monthly release.  Parrot releases the third Tuesday of each month.

Have fun!

[1] http://www.frozen-perl.org/
[2] http://use.perl.org/~pmichaud/journal/39779
[3] http://use.perl.org/~pmichaud/journal/39874

Re: One-pass parsing and forward type references

[Patrick R. Michaud]

On Sun, Jan 31, 2010 at 06:35:14PM +0100, Carl Mäsak wrote:
> I found two ways. Either one uses C (the language construct
> formerly known as C):
> 
>   class B {}
>   class A { sub foo { B::bar } }
>   augment class B { sub bar { A::foo } }
> 
> ...or one may use the C<::> notation to index a type using a string value:
> 
>   class A { sub foo { ::<&B::bar>() } }
>   class B { sub bar { A::foo } }

There's a third way:

class B { ... }# introduce B as a class name without definition
class A { sub foo { B::bar } }

class B { sub bar { A::foo } }

The first line is a literal "..." in the body of the class -- it
indicates that we're only declaring the name as being a type,
and that something else will fill in the details later.

Pm

Re: Debugging Grammars

[Patrick R. Michaud]

On Sun, Dec 27, 2009 at 01:30:18AM -0800, Ovid wrote:
> 
> my $config = Config::Tiny::Grammar.parse($text);
> #say $config ?? 'yes' || 'no';
> say $config.perl;
> 

> Currently this matches, but if I add a \s* before the final \n 
> in the section token, it fails to match.  I don't know why 
> this is and I'm unsure of how to debug Perl 6 regexes.

Any \s* will end up matching the final \n, and since quantifiers
in tokens default to "non backtracking", \s* \n in a token will 
always fail.  (In P5, it'd be like "(?>\s*)\n".)  Perhaps 
\h* \n would do what you want here?

Alternatively, you can force backtracking by using \s*! instead.

The new version of Rakudo (the "ng" branch) provides a debugging
mode that provides some tracing of the grammar as its matching.
I don't know that it would've found the above yet -- it still needs
some work.

> my $config = Config::Tiny::Grammar.parse($text);
> #say $config ?? 'yes' || 'no';
> say $config.perl;
>
> Also, if I uncomment that 'say $config ??' line, I get the 
> following strange error:
> 
>   ResizablePMCArray: Can't pop from an empty array!
>   in Main (file , line ) 

It's a parsing error in Rakudo at the moment -- it *should* be 
telling you that it found a '??' but no '!!'.  Again, the new
version (arriving in a week or so) should be better about such
messages.

Pm

Re: r29381 - docs/Perl6/Spec

[Patrick R. Michaud]

On Sat, Dec 19, 2009 at 03:29:21PM -0800, Jon Lang wrote:
> What if I need to make a new type that, like junctions,
> should not derive from Any, but isn't a junction?  Is it that
> explicitly deriving from a type that's already outside of Any (such as
> Mu or junction) automatically disables the implicit Any derivation?

Yes.

Pm

Re: p6 Q: How do I metaprogram this?

[Patrick R. Michaud]

On Wed, Dec 09, 2009 at 12:16:32AM -0500, Austin Hastings wrote:
> >>But I'm curious if there's some P6 feature I've forgotten about
> >>(which I've forgotten most of them, excepting the rev number)
> >>that would let me do this without having to go too far away from
> >>the metal.
> 
> Coming at this from a different angle, C# offers syntactic sugar for
> getter/setter methods. This example of mine might be a candidate for
> a macro, depending on the language. But is this a p6 macro? Or is
> there some in-between that I just don't know about.

In Perl 6, getter and setter methods are generated automatically
for most attributes that are declared with a dot twigil.  Writing

has $.xyz;

in a class declaration (note the dot twigil) automatically 
defines a getter method for the class that is similar to:

multi method xyz() { $!xyz }

And writing 

has $.xyz is rw;

automatically creates a getter/setter method that allows both
read and write access to the invocant's $!xyz attribute.

I've thought briefly about having NQP automatically create
getter methods as well, but for the moment it feels safer to
not do this and require them to be written explicitly.  Writing 
p6-like setter (rw) methods in NQP is a real pain at the moment,
because native Parrot doesn't have a convenient mechanism for
a method to return a reference to an attribute slot.  (In other 
words, there's not a good way in core Parrot to do the equivalent 
of  "foo() := $value;"  or  "$obj.method() := $value;" .)

Pm

Re: error installing Perl6

[Patrick R. Michaud]

On Thu, Nov 12, 2009 at 12:49:01PM -0800, Darren Duncan wrote:
> I think that a best practice these days is to download and build Parrot  
> separately (which can be in a custom location) and then separately 
> download and configure Rakudo to use Parrot's location, rather than use 
> gen_parrot.  Parrot is gotten with Subversion, and Rakudo with Git.  I 
> could be wrong. -- Darren Duncan

It's still often hard to know *which* revision of Parrot to get --
Rakudo doesn't always build against Parrot HEAD.  (Phrased differently,
sometimes Parrot introduces a change that breaks Rakudo until we
have a chance to catch up.)

So, for people whose primary aim is to build Rakudo, we continue 
to recommend the --gen-parrot approach.  That gives the best
shot at getting something working.

If the primary aim is to build and install Rakudo for a more
"site wide" purpose, then installing Parrot first and building
Rakudo to use that makes more sense.  But one has to be careful
to match the Rakudo version with the corresponding Parrot version
(in build/PARROT_REVISION of the Rakudo repository).

Pm



>
> Richard Hainsworth wrote:
>> Just got error from new clone rakudo directory, Viz.
>>
>> rich...@jupiter:~/Development$ git clone git://github.com/rakudo/rakudo.git
>> Initialized empty Git repository in /home/richard/Development/rakudo/.git/
>> remote: Counting objects: 22035, done.
>> remote: Compressing objects: 100% (5908/5908), done.
>> remote: Total 22035 (delta 16176), reused 21484 (delta 15720)
>> Receiving objects: 100% (22035/22035), 2.92 MiB | 925 KiB/s, done.
>> Resolving deltas: 100% (16176/16176), done.
>> rich...@jupiter:~/Development$ cd rakudo/
>> rich...@jupiter:~/Development/rakudo$ perl Configure.pl --gen-parrot
>> Generating Parrot ...
>> /usr/bin/perl build/gen_parrot.pl  
>> --prefix=/home/richard/Development/rakudo/parrot_install --optimize
>>
>> Checking out Parrot r42403 via svn...
>> Can't exec "svn": No such file or directory at build/gen_parrot.pl line 47.
>>
>> Configuring Parrot ...
>> /usr/bin/perl Configure.pl  
>> --prefix=/home/richard/Development/rakudo/parrot_install --optimize
>> Unknown option: prefix
>> Unknown option: optimize
>> ===SORRY!===
>> Unable to locate parrot_config
>>
>> To automatically checkout (svn) and build a copy of parrot r42403,
>> try re-running Configure.pl with the '--gen-parrot' option.
>> Or, use the '--parrot-config' option to explicitly specify
>> the location of parrot_config to be used to build Rakudo Perl.
>>
>>
>> Building Parrot ...
>> ===SORRY!===
>> Unable to locate parrot_config
>>
>> To automatically checkout (svn) and build a copy of parrot r42403,
>> try re-running Configure.pl with the '--gen-parrot' option.
>> Or, use the '--parrot-config' option to explicitly specify
>> the location of parrot_config to be used to build Rakudo Perl.
>

Re: Implicit die in CATCH blocks

[Patrick R. Michaud]

On Sat, Sep 19, 2009 at 06:35:45PM -0400, Kodi Arfer wrote:
> In the process of writing some more tests for CATCH blocks, I've noticed  
> what appears to be a contradiction between Synopsis 4 on the one hand  
> and pugs/t/spec/S04-statements/try.t and Rakudo's current behavior on  
> the other. 

The short answer is that Rakudo's implementation of exceptions doesn't
match the specification yet.  We still have quite a bit of work to do
there.

Pm

Re: How can i contribute for perl 6 ?

[Patrick R. Michaud]

On Tue, Sep 15, 2009 at 11:16:56AM -0500, Kyle Hasselbacher wrote:
> On Mon, Sep 14, 2009 at 11:00 PM, Saravanan Thiyagarajan
>  wrote:
> 
> > Would like to be a volunteer in working for perl-6.
> > Can some one help me to get into right direction ?
> 
> This is how I did it:  http://perlmonks.org/?node_id=780001

Now added to http://rakudo.org/how-to-help .  Perhaps we also need
a "how to get involved" section on perl6.org ...?

Pm

Re: How can i contribute for perl 6 ?

[Patrick R. Michaud]

On Tue, Sep 15, 2009 at 10:02:02PM +1000, Timothy S. Nelson wrote:
> On Tue, 15 Sep 2009, Saravanan Thiyagarajan wrote:
>
>> Would like to be a volunteer in working for perl-6.
>> Can some one help me to get into right direction ?
>
>   Sure.  The best way to help depends on your skill-set.  One place to  
> start is at http://www.rakudo.org/how-to-help
> [...]

See also http://use.perl.org/~masak/journal/39445 , which undoubtedly
ought to be preserved somewhere on rakudo.org .

Pm

Re: r28196 - docs/Perl6/Spec

[Patrick R. Michaud]

On Mon, Sep 07, 2009 at 09:56:51AM -0700, yary wrote:
> I just saw the intent for this in the " split up compilation of the
> setting" thread- that it is useful to:
> >Enable a "class stub" syntax that allows us to declare a given symbol
> > as being a valid class without having to declare the body of the
> > class at that time.  For example:
> >
> > class Rat { ... };
> 
> I can agree with that so long as the "yada" is the only token inside
> the brackets. On the other hand why not go along with C convention and
> allow
> 
> class Rat;

We can't use this one -- it already means something different 
(namely, that the rest of the file is the specification for class Rat).

Pm

Re: r28113 - docs/Perl6/Spec

[Patrick R. Michaud]

On Mon, Aug 31, 2009 at 01:28:08PM -0700, Darren Duncan wrote:
> This is a great move; thanks for this change.
>
> So now writing things like 5/43 in code will DWIM and produce a Rat which 
> maintains the intended value exactly, with no floating-point imprecision; 
> and so plain 5/43 is now a plain Rat literal, same as 1.23 is.

FWIW, presently the specification somewhat implies that 1.23 is a Num 
literal, and doesn't say anything about it producing a Rat.  
(Yes, conversations on #perl6 have indicated that it may be otherwise, 
but nothing is currently in the spec about it.)  

S02:401 :
One consequence of all this is that you may no longer write a Num as
C<42.> with just a trailing dot.  You must instead say either C<42>
or C<42.0>.

Pm

Re: [perl #64566] @a[1..*] adds trailing undef value

[Patrick R. Michaud]

On Wed, Aug 19, 2009 at 04:54:10AM -0700, Moritz Lenz via RT wrote:
> On Wed Apr 08 14:59:19 2009, moritz wrote:
> > 23:55 <@moritz_> rakudo: my @a = 1..4; say @a[1..*].perl
> > 23:56 < p6eval> rakudo 6b9755: OUTPUT«[2, 3, 4, undef]␤»
> > 
> > It should just be [2, 3, 4].
> 
> Since the discussion came up on #perl6 if this is really the expected
> behaviour, S09 says:
> 
> As the end-point of a range, a lone "whatever" means "to the maximum
> specified index" (if fixed indices were defined):
> 
> say @calendar[5..*];  # Same as:  say @calendar[5..11]
> say @calendar{Jun..*};# Same as:  say @calendar{Jun..Dec}
> 
> or "to the largest allocated index" (if there are no fixed indices):
> 
> say @data[1..*];  # Same as:  say @results[1..5]
> 
> 
> It doesn't mention how the postcifcumfix:<[ ]> is supposed to introspect
> those to find out if the WhateverCode object constructed by 1..* needs
> to receive self.elems or self.elems-1 as an argument.

The short answer is that 1..* isn't a WhateverCode object, it's a Range
with a Whatever endpoint.  (Rakudo currently gets this wrong, yes.)
So postcircumfix:<[ ]> then changes its dispatch based on having a
Range argument.

Pm

Re: Embedded comments: two proposed solutions to the comment-whole-lines problem

[Patrick R. Michaud]

On Mon, Aug 10, 2009 at 06:46:34PM +0100, smuj wrote:
> Although I can see some minimal uses for embedded comments, I think in  
> general the cost/benefit ratio isn't enough to warrant their existence.  
> I could be wrong of course! :-) I'd like to know if anyone has made much  
> use of them in their code, and under what circumstances.

I've used embedded comments a number of times (especially in examples)
and found them to be incredibly useful.  I'd be sad to see them disappear.

I'd be fine with the ##(embedded comment solution) approach (doubling
the #'s), but it's much less visually appealing to me.  I think I'd 
prefer to see a doubling of the bracketing chars instead of doubling 
the #'s -- the # is visually a "heavy" glyph and I'd prefer 
something a bit lighter.

#((embedded comment))
#{{embedded comment}}

Pm

Re: Rukudo-Star => Rakudo-lite?

[Patrick R. Michaud]

On Sun, Aug 09, 2009 at 04:35:42PM -0600, David Green wrote:
> On 2009-Aug-9, at 3:57 pm, Tim Bunce wrote:
>> Perhaps it's worth asking what we might call the release after that  
>> one.
>> "Rakudo not-quite-so-lite"?
>
> Rakudo ** (aka "Rakudo Exponentiation")?  Though I think Patrick is  
> optimistic that development will proceed exponentially enough that a  
> single interim release will be enough to hold us over until Christmas.

I'm not sure I'm quite THAT optimistic.  :-)  We may end up with 
multiple interim releases in the Rakudo Star series before we reach 
Christmas.  (And yes, they may even be *+1, *+2, etc.)

In some ways I'm starting to think of "Star" (or whatever designation
we end up using) as a label for a series of interim releases in the
same sense that NASA used "Gemini" as the label for the program
came between "Mercury" and "Apollo".  

In other words, "Star" may really end up being a designation for a 
program of planned releases with certain major objectives that 
cumulatively lead up to the ultimate goal of a "full Perl 6 release".

The precise details are still a little ill-formed in my head at the 
moment, but as they come together (and are expressed in planning 
documents) I'll be blogging or writing about them appropriately.

Pm

Re: Rukudo-Star => Rakudo-lite?

[Patrick R. Michaud]

On Sun, Aug 09, 2009 at 10:57:16PM +0100, Tim Bunce wrote:
> > > Since Rakudo* (not sure how it is to be written) is intended to be a  
> > > cut-down version of perl6.0.0 that is useable, how about Rakudo-lite?
> > 
> > Hmmm, that's a very reasonable name.  Over the past few days I've
> > become a little attached to "Rakudo Star", but I agree that
> > "Rakudo light" might be a bit more descriptive.  I'll have to
> > mull it over a while.
> [...]
> I like "Rakudo Star". It doesn't try to be descriptive. It's just a name.

Based on #perl6 discussions and a few other threads, I've decided
we'll stick with "Rakudo Star".  It's non-descriptiveness is an asset
at this point.

Pm

Re: Rukudo-Star => Rakudo-lite?

[Patrick R. Michaud]

On Sun, Aug 09, 2009 at 04:30:07PM +0400, Richard Hainsworth wrote:
> Referring to Patrick's blog about an official 'useable' version of  
> Rakudo, a suggestion:
>
> Since Rakudo* (not sure how it is to be written) is intended to be a  
> cut-down version of perl6.0.0 that is useable, how about Rakudo-lite?

Hmmm, that's a very reasonable name.  Over the past few days I've
become a little attached to "Rakudo Star", but I agree that
"Rakudo light" might be a bit more descriptive.  I'll have to
mull it over a while.

Pm

Re: S05 (regex) Q:

[Patrick R. Michaud]

On Sat, Aug 08, 2009 at 05:45:40PM -0400, Austin Hastings wrote:
> [...]
> Specifically, is
> token { ...  }
> going to match the same pattern as
> rule { ...  }
> ??
>
> I ask because (I just did it, and) with rules encouraging the liberal  
> use of whitespace, and implicitly generating <.ws> matches, something 
> like:
> rule { X  }
> will insert a <.ws> before the , which the after-block should  
> then be aware of.

Why should the after-block be (automatically?) aware of the <.ws>?

Put another way, afaik  is just a subrule like any 
other -- it doesn't get any special syntactic significance
that enables it to be aware of its surroundings.  I would say that
the rule should be either

rule { X }

or if checking the whitespace is desired, it should be

rule { X  }   # note whitespace after the X

> So, I suppose the question is, does  always behave a certain  
> way, ratchet-wise, and if so what is it? Or does it take its mode from  
> the surrounding context, or something else?

Ultimately I think that  behaves the same as any other
subrule, and its pattern takes its ratchet/sigspace mode from the 
surrounding pattern scope.

Pm

Re: r27888 - docs/Perl6/Spec

[Patrick R. Michaud]

On Fri, Aug 07, 2009 at 08:17:30AM +0200, Moritz Lenz wrote:
> pugs-comm...@feather.perl6.nl wrote:
> > Author: jimmy
> > Date: 2009-08-07 05:02:42 +0200 (Fri, 07 Aug 2009)
> > New Revision: 27888
> > 
> > Log:
> > [Spec]fixed the wrong space, now it's \x20, not \xC2A0
> 
> What was wrong with the non-breaking spaces?
> We use "Perl 5" and "Perl 6" as words, so it makes a lot of sense to
> separate them by non-breaking spaces, IMHO.
> 
> Also note that this commit breaks 22 smartlinks.

I vote to revert this change and keep the non-breaking space.

Pm

Re: Placeholder variable misuse.

[Patrick R. Michaud]

On Thu, Jul 30, 2009 at 10:29:04AM -0500, Kyle Hasselbacher wrote:
> In Rakudo right now, this lives:  "{$foo;$^foo}(1)"
> 
> However, the spec test expects it to die during compilation (see the
> end of S06-signature/positional-placeholders.t).  It says, "A
> non-twigil variable should not precede a corresponding twigil
> variable."

The spec is correct.  Rakudo currently has some issues with
order-of-lexicals declarations.


> In Rakudo right now, this says 3:  sub foo { my $a = 3; say $^a };
> foo(5);  # RT #64310
> The spec test would seem to imply that this should die during the
> definition of 'foo'.

Rakudo should complain about the placeholder attempting to redefine $^a.
I don't know if that elevates to the level of "die", though; STD.pm
seems to treat it as a "potential difficulty".

> On the other hand, if we swap the statements, it merely complains that
> $a is redeclared and then croaks because we assigned to a read-only
> variable.
> 
> sub foo { say $^a; my $a = 3 }; foo(5);
> Redeclaration of variable $a
> 5
> Cannot assign to readonly variable.

Rakudo is correct that it's a redeclaration and that the
variable (parameter) is readonly and cannot be assigned to.

Pm

Re: Parameter binding

[Patrick R. Michaud]

On Thu, Jul 23, 2009 at 05:56:31PM +0200, TSa wrote:
> Hmm, it seems to be the case that the binding is defined to be a
> readonly binding to the variable. I consider this a bad thing.
> We should have my $x = 1; foo($x++,$x,$x++); to call foo(1,2,2)
> and not foo(1,3,2) or even foo(2,3,1). The capture creation for
> the foo call should be strictly left to right and capturing the
> value at that moment.

...except that captures don't capture values -- they form references.

Pm

Re: XOR does not work that way.

[Patrick R. Michaud]

On Thu, Jun 25, 2009 at 02:47:55PM +1000, Timothy S. Nelson wrote:
>   What would happen if we had an operator that returned the number of  
> true values?  Say we call it "boolean plus", or "bop".

...why an operator?

   sub bop(*...@values) { + grep { $_ }, @values }

>   To give one example: 1 bop 3 = 2

   bop 1, 3

>   Say we're looking at: ($x > 1) bop 3 bop ($y < 0)

   bop ($x > 1), 3, ($y < 0)


>   To get the boolean-logic definition, we'd do:
>   ($x > 1) bop 3 bop ($y < 0) % 2

   bop ($x > 1), 3, ($y < 0) % 2

>   To get the natural-language one, we'd do:
>   ($x > 1) bop 3 bop ($y < 0) == 1

   bop ($x > 1), 3, ($y < 0) == 1

Pm

Rakudo Perl 6 development release #18 ("Pittsburgh")

[Patrick R. Michaud]

On behalf of the Rakudo development team, I'm pleased to announce
the June 2009 development release of Rakudo Perl #18 "Pittsburgh".
Rakudo is an implementation of Perl 6 on the Parrot Virtual Machine [1].
The tarball for the June 2009 release is available from
http://github.com/rakudo/rakudo/downloads .

Due to the continued rapid pace of Rakudo development and the
frequent addition of new Perl 6 features and bugfixes, we continue
to recommend that people wanting to use or work with Rakudo obtain
the latest source directly from the main repository at github.
More details are available at http://rakudo.org/how-to-get-rakudo .

Rakudo Perl follows a monthly release cycle, with each release code named
after a Perl Mongers group.  This release is named "Pittsburgh", which
is the host for YAPC|10 (YAPC::NA 2009) [2] and the Parrot Virtual Machine
Workshop [3].  Pittsburgh.pm has also sponsored hackathons for Rakudo 
Perl as part of the 2008 Pittsburgh Perl Workshop [4].

In this release of Rakudo Perl, we've focused our efforts on refactoring
many of Rakudo's internals; these refactors improve performance, 
bring us closer to the Perl 6 specification, operate more cleanly
with Parrot, and provide a stronger foundation for features to be
implemented in the near future.  Some of the specific major changes
and improvements in this release include:

* Rakudo is now passing 11,536 spectests, an increase of 194
  passing tests since the May 2009 release.  With this release
  Rakudo is now passing 68% of the available spectest suite.

* Method dispatch has been substantially refactored; the new dispatcher
  is significantly faster and follows the Perl 6 specification more
  closely.

* Object initialization via the BUILD and CREATE (sub)methods is
  substantially improved.

* All return values are now type checked (previously only explicit
  'return' statements would perform type checking).

* String handling is significantly improved: fewer Unicode-related
  bugs exist, and parsing speed is greatly improved for some programs 
  containing characters in the Latin-1 set.

* The IO .lines and .get methods now follow the specification more closely.

* User-defined operators now also receive some of their associated 
  meta variants.

* The 'is export' trait has been improved; more builtin functions
  and methods can be written in Perl 6 instead of PIR.

* Many Parrot changes have improved performance and reduced overall
  memory leaks (although there's still much more improvement needed).

The development team thanks all of our contributors and sponsors for
making Rakudo Perl possible.  If you would like to contribute,
see http://rakudo.org/how-to-help , ask on the perl6-compi...@perl.org
mailing list, or ask on IRC #perl6 on freenode.

The next release of Rakudo (#19) is scheduled for July 23, 2009.
A list of the other planned release dates and codenames for 2009 is
available in the "docs/release_guide.pod" file.  In general, Rakudo
development releases are scheduled to occur two days after each
Parrot monthly release.  Parrot releases the third Tuesday of each month.

Have fun!

References:
[1]  Parrot, http://parrot.org/
[2]  YAPC|10 http://yapc10.org/yn2009/
[3]  Parrot Virtual Machine Workshop, http://yapc10.org/yn2009/talk/2045
[4]  Pittsburgh Perl Workshop, http://pghpw.org/ppw2008/

Re: CPAN -- moving forward

[Patrick R. Michaud]

On Mon, Jun 01, 2009 at 06:34:02PM +0200, Daniel Carrera wrote:
> I am in IRC  
> working with Rakudo folk on how Rakudo is going to store modules on the  
> disk. Once that is done, one can begin talking about a package format  
> and an installer, and then go from there.
>
> So far the discussion has been productive and we have some code written  
> that we can experiment with. So I feel encouraged.

"Rough concensus and running code."  +1

Pm

Re: Module naming conventions

[Patrick R. Michaud]

On Tue, Jun 02, 2009 at 10:58:21AM +0200, Daniel Carrera wrote:
> John M. Dlugosz wrote:
>> The front-end should figure out which binary is proper for your  
>> platform.
>
> I don't like that idea in the slightest. (1) It is not Perl's job to  
> know if you have a C compiler, C libraries and tool chain. (2) If my  
> computer can handle Perl, C and Parrot, I want the choice of what to  
> install. (3) That includes the possibility of installing more than one  
> module. It is perfectly legitimate to install three implementations of  
> SHA (one in C, one in Parrot and one in pure Perl). This last one means  
> that there has to be a way to tell Perl which of the Digest::SHA modules  
> I want to use for this particular program.
>
> Suppose I want to install three versions of SHA. One in C, one in Perl,  
> one in Parrot. I need a way to specify in the "use" statement which one  
> I want.

For the Parrot case at least, I suspect one would/could do:

use SHA:from;

(See the :from adverb in S11.)

Indeed, for someone who is running an implementation of Perl 6
on Parrot (and where a Parrot-specific implementation of SHA is
available), I would expect a plain "usa SHA;" to load SHA.pm
which then in turn does the :from version of use.  Or 
any other number of implementation-specific tricks that can hide the
details for a generic "use SHA" but still make it possible for
more specific requirements to be made.

Pm

Re: Module naming conventions

[Patrick R. Michaud]

On Tue, Jun 02, 2009 at 02:56:46AM +0200, Daniel Carrera wrote:
> Jon Lang wrote:
>> On Mon, Jun 1, 2009 at 5:44 PM, Daniel Carrera
>>  wrote:
>>> I think we might need to come up with some sort of standard naming
>>> convention to distinguish dependencies. Something that the *user* can
>>> recognize quickly when he browses CPAN.
>>
>> Why do we need the dependencies to be part of the name?  Perl 6
>> provides a rugged versioning system for its modules; we should use it.
>
> I read S11 and AFAICT Perl 6 only includes metadata for *versions* and  
> *authority*:
>
> class Dog:ver<1.2.1>:auth;
> class Dog:ver<1.2.1>:auth;
> class Dog:ver<1.2.1>:auth;

Just because these are the only adverbs mentioned doesn't necessarily
mean they're the only ones that will be allowed.  Indeed, S11 goes
on to later say:

"The required parts for library insertion are the short name of
the class/module, its version number, and a URI identifying the 
author (or authorizing authority, so we call it "auth" to be 
intentionally ambiguous)."

The fact that S11 says "required parts" leads me to believe that
there can be other parts that aren't required.

Pm

Re: Amazing Perl 6

[Patrick R. Michaud]

On Fri, May 29, 2009 at 10:04:39AM -0700, Larry Wall wrote:
> On Fri, May 29, 2009 at 09:50:36AM -0700, yary wrote:
> : Show that much of the basics still work:
> : > my @x=('a' .. 'z'); @x[3,4]=qw(DeeDee Ramone);
> :   say @x.splice(2,4).join(',')
> : c,DeeDee,Ramone,f
> 
> That qw is not a good example of what still works, since it is supposed
> to be interpreted as a qw subroutine (rakudo bug).  I recommend square
> brackets instead.

And Rakudo now correctly treats qw() like a function instead of
a quote:

  $ ./perl6
  > say qw(DeeDee Ramone);
  Could not find non-existent sub Ramone
  > say qw (DeeDee Ramone);
  DeeDeeRamone
  > say qw[DeeDee Ramone];
  DeeDeeRamone
  > 

Thanks Larry!

Pm

Re: Feature request: Grammar debugging support

[Patrick R. Michaud]

On Fri, May 29, 2009 at 11:20:20AM -0700, Larry Wall wrote:
> Can't help you with PGE, but STD supports a trace facility by
> setting the STD5DEBUG environent variable to -1, or a set of bits
> defined in src/perl6/Cursor.pmc in the pugs repo.

I'll look at what STD is using for its traces and see if I can
come up with something similar for PGE.

Pm

Re: Meditations on a Loop

[Patrick R. Michaud]

On Tue, May 26, 2009 at 04:10:45PM -0700, yary wrote:
> On Tue, May 26, 2009 at 1:57 PM, Patrick R. Michaud  
> wrote:
> > On Mon, May 25, 2009 at 12:37:34PM -0700, yary wrote:
> > How about...?
> >
> >    sub odd { ^$a % 2 }
> typo. "sub odd {$^a % 2}" works (caret goes between "$" and "a")

Correct, that's a typo.

> >    say grep &odd, 0..6;
> nice. I need to learn the differences between calling a sub as "odd"
> vs "&odd" in p6. Haven't gotten that far in the synopses yet.

In p6, one always uses the sigil to refer to the sub itself; the bare
identifier form invokes it.

> I was wondering why the perl5 example didn't work in p6- $_ is a
> contextual variable, so why doesn't the body of "odd" get its $_ value
> from grep in something like this:
> sub odd_a { $_ % 2}

This is really equivalent to

sub odd_a(*...@_, *%_) { $_ % 2 }

Every Routine gets its own $_ that isn't inherited from the outer 
lexical context (and is initialized to undef).  

Beyond that, what is really happening with

say grep &odd_a, 0..6

is that grep is performing a smart-match of each value of 0..6 
with &odd_a, and smart-matching a value to a Code object invokes
the Code object with the value as an argument.

Pm

Re: Unexpected behaviour with @foo.elems

[Patrick R. Michaud]

On Tue, May 26, 2009 at 06:43:40PM -0500, John M. Dlugosz wrote:
> Daniel Carrera daniel.carrera-at-theingots.org |Perl 6| wrote:
>> The following construction doesn't do what a user might expect:
>>
>> for 0...@foo.elems -> $k { do_something($k,@foo[$k]) }
>
> Write ^...@foo.elems as a shortcut of 0...@foo.elems, which is the
> variation to exclude that endpoint if you would rather not write
> 0...@foo.elems-1.

An even cleaner shortcut might be to use ^...@foo instead of ^...@foo.elems:

for ^...@foo -> $k { do_something($k, @foo[$k]) }

Somewhat clearer could be:

for @foo.keys -> $k { do_something($k, @foo[$k]) }

And some may prefer:

for @foo.kv -> $k, $v { do_something($k, $v) }

I think the anti-pattern of "0...@foo.elems" (or its incorrect
form "0...@foo.elems") should probably disappear in favor of
the above forms instead.

Pm

Re: Meditations on a Loop

[Patrick R. Michaud]

On Mon, May 25, 2009 at 12:37:34PM -0700, yary wrote:
> That's an enjoyable and educational read, thanks!
> 
> There's one form under TMTOWTDI that I'd like to see, but can't figure
> out myself. It's the version analogous to this perl5 snippet-
> 
>   sub odd {$_ % 2}
>   say grep odd,0..6;
>
> -where the line that filters the list mentions no variables at all,
> and "$_" does its work behind the curtains.

How about...?

sub odd { ^$a % 2 }
say grep &odd, 0..6;

This gets us to within one character of the p5 version.  I think 
we also have the possibility of

subset odd where { $_ % 2 }
say grep odd, 0..6;

which is the same length as the p5 version, but afaict this 
last one doesn't seem to be working in Rakudo yet.

Pm

Rakudo Perl 6 development release #17 ("Stockholm")

[Patrick R. Michaud]

On behalf of the Rakudo development team, I'm pleased to announce
the May 2009 development release of Rakudo Perl #17 "Stockholm".
Rakudo is an implementation of Perl 6 on the Parrot Virtual Machine [1].
The tarball for the May 2009 release is available from
http://github.com/rakudo/rakudo/downloads .

Due to the continued rapid pace of Rakudo development and the
frequent addition of new Perl 6 features and bugfixes, we continue
to recommend that people wanting to use or work with Rakudo obtain
the latest source directly from the main repository at github.
More details are available at http://rakudo.org/how-to-get-rakudo .

Rakudo Perl follows a monthly release cycle, with each release code named
after a Perl Mongers group.  This release is named "Stockholm";
Stockholm Perl Mongers will be holding a Perl 6 hackathon on May 29 [3].
Perl 6 developer Carl Mäsak is a member of Stockholm Perl Mongers and
a main author of November [4], Druid [5], proto [6], and other
Perl 6-based packages.  Carl also contributes patches to Rakudo,
and has been stress-testing Rakudo over the past year, submitting
nearly 400 bug reports.

In this release of Rakudo Perl, we've made the following major changes
and improvements:

* Rakudo is now passing 11,342 spectests, an increase of 875
  passing tests since the April 2009 release.  With this release
  Rakudo is now passing 68% of the available spectest suite.

* We now have an updated docs/ROADMAP .

* Errors and stack traces now report the file name and line number
  in the original source code.

* Some custom operators can be defined, and it's possible to
  refer to operators using &infix: syntax.

* We can start to load libraries written in other Parrot languages.

* Regexes now produce a Regex sub.

* More builtin functions and methods have been rewritten in
  Perl 6 and placed as part of the setting.

* There are many additional improvements and features in this release,
  see docs/ChangeLog for a more complete list.

The development team thanks all of our contributors and sponsors for
making Rakudo Perl possible.  If you would like to contribute,
see http://rakudo.org/how-to-help , ask on the perl6-compi...@perl.org
mailing list, or ask on IRC #perl6 on freenode.

The next release of Rakudo (#18) is scheduled for June 18, 2009.
A list of the other planned release dates and codenames for 2009 is
available in the "docs/release_guide.pod" file.  In general, Rakudo
development releases are scheduled to occur two days after each
Parrot monthly release.  Parrot releases the third Tuesday of each month.

Have fun!

References:
[1]  Parrot, http://parrot.org/
[2]  Stockholm.pm, http://sthlm.pm.org/
[3]  Stockholm Perl 6 hackathon, 
http://vic20.blipp.com/pipermail/kameler/2009-May/000318.html
[4]  November wiki engine, http://github.com/viklund/november/
[5]  Druid, http://github.com/masak/druid/
[6]  Proto, http://github.com/masak/proto/

Re: Meditations on a Loop

[Patrick R. Michaud]

On Wed, May 20, 2009 at 07:55:55PM -0500, John M. Dlugosz wrote:
> If you would be so kind, please take a look at  
> .  

The page currently says:

"The reason this [.prime] works is because the method-call 
syntax will call an ordinary non-member sub also."

I think this is no longer the case (and hasn't been for some time).

Pm

Re: Whitespace in \c[...], \x[...], etc.

[Patrick R. Michaud]

On Tue, Apr 28, 2009 at 03:08:05PM -0400, Mark J. Reed wrote:
> On Tue, Apr 28, 2009 at 2:27 PM, Patrick R. Michaud  
> wrote:
> > * The Unicode character name database [2] has parens in the
> >  name property field for many characters
> >
> >    000A;;Cc;0;B;N;LINE FEED (LF)
> 
> That's not the name property field.  The Unicode character name is
> field 1 ("", in this case).  The field whose value is "LINE
> FEED (LF)" is the Unicode_1_Name field, wihch for control characters
> supplies the ISO 6429 name.

Ah, thanks for the excellent clarification.

Returning to the original question:  Would this then mean
that we don't provide a way to specify U+000A and other control
characters using a "name" inside of \c[...]?

Or (more likely) does it mean that the names we accept inside
of the \c[...] are more than just the strict
"Unicode character names" listed above--i.e., the Unicode_1_Name
field and other related aliases (whatever those might be)?

Pm

Re: Whitespace in \c[...], \x[...], etc.

[Patrick R. Michaud]

On Tue, Apr 28, 2009 at 07:22:18AM -0700, Larry Wall wrote:
> On Mon, Apr 27, 2009 at 11:04:03AM +0200, Helmut Wollmersdorfer wrote:
> > Std.pm allows e.g.
> >
> >   "\x[   41  ,   42  ,  43  ]"
> >
> > For convenience - especially with long charnames - it should be possible  
> > to write
> >
> > "\c[
> > SPACE, # blafasel
> > LATIN SMALL LETTER A,  # some comment
> > COMBINING DOT BELOW,   # thisandthat
> > ]"
> 
> In any case, STD doesn't currently try to check the string in \c[...]
> for correctness.  It just scans for the closing bracket.  We will
> certainly need to refine this, and the suggested approach is certainly
> a possible outcome, if we decide it's sufficiently unambiguous.

FWIW, Rakudo and PGE now allow spaces inside the brackets, although they 
don't understand the # ... comments yet.

Pm

Re: Whitespace in \c[...], \x[...], etc.

[Patrick R. Michaud]

On Tue, Apr 28, 2009 at 01:28:40PM -0400, Mark J. Reed wrote:
> On Tue, Apr 28, 2009 at 10:22 AM, Larry Wall  wrote:
> > Does anyone know offhand whether the Unicode Consortium has an explicit
> > policy against use of punctuation in a charname?  So far they only
> > seem to use hyphen and parens, but I wonder to what extent we can
> > depend on that...
> 
> According to the 5.0.0 standard, section 4.8:
> 
> "Unicode character names contain only uppercase Latin letters A
> through Z, digits, space, and hyphen-minus."
> 
> So it seems the notes in parentheses are not considered part of the char name.

Countering this, though:

* The XML schema for the "Unicode Character Database in XML" [1] 
  seems to allow parens in the character name property:

character-name = xsd:string { pattern="([A-Z0-9 #\-\(\)]*)|()" } 

* The Unicode character name database [2] has parens in the
  name property field for many characters

000A;;Cc;0;B;N;LINE FEED (LF)

* ICU doesn't seem to recognize the versions of the name without
  the parens (or if it does, I haven't been able to figure out the
  correct incantations to make it do so).

Of course, it's very possible that I'm misreading the Unicode
specifications, and the note that Mark cites would seem to be
very explicit.  But thus far in playing with this I've seen
more indications that the parens are allowed or even required
than I've seen that indicate they're excluded.

Pm

[1] http://www.unicode.org/reports/tr42/tr42-3.html#N66310
[2] http://unicode.org/Public/UNIDATA/UnicodeData.txt

Rakudo Perl 6 development release #16 ("Bratislava")

[Patrick R. Michaud]

On behalf of the Rakudo development team, I'm pleased to announce
the April 2009 development release of Rakudo Perl #16 "Bratislava".
Rakudo is an implementation of Perl 6 on the Parrot Virtual Machine [1].
The tarball for the April 2009 release is available from
http://github.com/rakudo/rakudo/downloads .

Due to the continued rapid pace of Rakudo development and the
frequent addition of new Perl 6 features and bugfixes, we continue
to recommend that people wanting to use or work with Rakudo obtain
the latest source directly from the main repository at github.
More details are available at http://rakudo.org/how-to-get-rakudo .

Rakudo Perl follows a monthly release cycle, with each release code named
after a Perl Mongers group.  This release is named "Bratislava",
home to Jonathan Worthington and reportedly an excellent place to
obtain beer (a key component of Jonathan's contributions to Perl).
The Bratislava.pm group is quite active [2], with regular technical
presentations and social gatherings.

In this release of Rakudo Perl, we've made the following major changes
and improvements:

* Rakudo is now passing 10,467 spectests, an increase of 3,194
  passing tests since the March 2009 release.  With this release
  Rakudo is now passing approximately 65% of the available
  spectest suite.

* About 2/3 of the increase in passing tests is due to improved
  Unicode support in Rakudo; constructs such as "\c[LATIN CAPITAL LETTER A]"
  and Unicode character properties in regexes are now supported.

* The prefix:<=> operator is now gone from the Perl 6 specification
  (and thus from Rakudo).  Use .get for reading individual items
  from iterators.

* Rakudo now supports typed arrays and hashes (my Int @array), as
  well as parametric versions of the Associative, Positional,
  and Callable roles, and parametric role subtyping.

* Rakudo now has sockets support (IO::Socket).

* Subroutine return types are now enforced in some cases.

* Rakudo now supports lexical sub declarations.

* Rakudo now supports some P5-style regexes.

* The "quantify-by-separator" feature has been added, so that
  one can write  / [\w+] ** ',' / to get a comma-separated
  list of words.

* More builtin functions and methods have been rewritten in
  Perl 6 and placed as part of the setting.

* Release tar files now contain local copies of the appropriate
  spectests, instead of obtaining checkout copies via Subversion.

* There are additional improvements and features in this release,
  see docs/ChangeLog for a more complete list.

The development team thanks all of our contributors and sponsors for
making Rakudo Perl possible.  If you would like to contribute,
see http://rakudo.org/how-to-help , ask on the perl6-compi...@perl.org
mailing list, or ask on IRC #perl6 on freenode.

The next release of Rakudo (#17) is scheduled for May 21, 2009.
A list of the other planned release dates and codenames for 2009 is
available in the "docs/release_guide.pod" file.  In general, Rakudo
development releases are scheduled to occur two days after each
Parrot monthly release.  Parrot releases the third Tuesday of each month.

Have fun!

References:
[1]  Parrot, http://parrot.org/
[2]  Bratislava.pm, http://bratislava.pm.org/

Oslo Perl 6 Hackathon Notes

[Patrick R. Michaud]

As some of you are aware, this week is the Nordic Perl Workshop [1],
and in the days immediately following the workshop we will have
the Oslo Perl 6 Hackathon [2].  During the first day of the hackathon
Gabor Szabo will be doing a "Hands-on Perl 6 training" course [3],
the other two days will be for various hacking tasks (both Perl 6
and Perl 5).

I personally have three goals for my participation at the 
workshop and hackathon:

*  Attend Gabor's course and take careful note of where issues
arise with using Rakudo Perl and/or Perl 6 (including filing
bug reports and/or answering questions as needed).

*  Recruit and encourage people to write Perl 6 programs and
otherwise start hacking on/with Rakudo Perl.

*  Meet with other principal Rakudo and Perl 6 designers and
implementors to plan the next phases of work and address any
significant obstacles currently before us.


For now I've started a page at 
http://www.perlfoundation.org/perl6/index.cgi?perl_6_hackathon_targets
that lists a variety of specific ideas for things to work on
or address at the hackathon.  I'm sure more ideas will arise
at NPW itself, and I invite others to add more items to the
list as well.  Feel free to add things even if you won't be
making it to NPW or the hackathon itself; you may think of something
that we've overlooked, and there are other hackathons planned later
in the summer that will benefit from having the ideas.

Thanks!

Pm

References:
[1] http://www.perlfoundation.org/perl6/index.cgi?oslo_perl_6_hackaton_2009
[2] http://www.perlfoundation.org/perl6/index.cgi?perl_6_hackathon_targets
[3] http://szabgab.com/blog/2009/03/1235863222.html

Re: S08 Draft questions (Captures and Signatures)

[Patrick R. Michaud]

On Wed, Apr 01, 2009 at 09:55:37AM -0300, Daniel Ruoso wrote:
> Em Qua, 2009-04-01 às 05:41 -0700, Jon Lang escreveu:
> > ...nor would I expect it to.  I'm just wondering if (@_, %_) _are_
> > still part of a placeholder-generated signature.  In short, is there a
> > way to access a slurpy array or hash in a block that uses placeholder
> > parameters?
> 
> I'd guess not, but I think it's a plain design decision. 

@_ and %_ are part of a placeholder-generated signature if
they're mentioned in the block.  From S06:154:

Note also that if the sub's block contains placeholder variables
(such as C<$^foo> or C<$:bar>), those are considered to be formal
parameters already, so in that case C<@_> or C<%_> fill the role of
sopping up unmatched arguments.  That is, if those containers are
explicitly mentioned within the body, they are added as slurpy
parameters. [...]

Pm

Re: Junction Algebra

[Patrick R. Michaud]

On Sat, Mar 28, 2009 at 10:19:31AM -0500, Patrick R. Michaud wrote:
> On Sat, Mar 28, 2009 at 02:08:22PM +0300, Richard Hainsworth wrote:
> > 3) Conjecture: The following is true of all junction types, eg.,
> > junc(..., junc(...)) === junc(..., ...)
> 
> The conjecture is false for one/none junctions:
> 
> one(0, one(1, 1)) # true
> one(0, 1, 1)  # false

Boy, I typoed that one.  I meant to write:

one(1, one(1, 1))   # true
one(1, 1, 1)# false

Pm

Re: Junction Algebra

[Patrick R. Michaud]

On Sat, Mar 28, 2009 at 02:08:22PM +0300, Richard Hainsworth wrote:
> 3) Conjecture: The following is true of all junction types, eg.,
> junc(..., junc(...)) === junc(..., ...)

The conjecture is false for one/none junctions:

one(0, one(1, 1)) # true
one(0, 1, 1)  # false

none(0, none(0, 0))   # false
none(0, 0, 0) # true

I'm still considering the any/all cases.

Pm

Re: On Junctions

[Patrick R. Michaud]

On Fri, Mar 27, 2009 at 05:49:02PM -0400, Henry Baragar wrote:
> I believe that there are hands where $p = 15|26 which would not beat a  
> hand where $d = 17.
>
> I believe that the correct way to calculate the "value of the hand" is:
>
>my $p = ([+] @p).map{.eigenstates}.grep{$_ < 21}.max;

Since the result of [+] is a scalar we don't need to 'map' it. 
Assuming that .eigenstates exists it would then be

my $p = ([+] @p).eigenstates.grep({ $_ < 21 }).max

Pm

deciphering infix:

[Patrick R. Michaud]

Rakudo gives some strange results when sorting a list
of mixed strings and numbers, which leads me to look
for some clarification on infix: (which S03:2866 says
that sort uses by default).   Here's the case I found
in Rakudo:

  > say ('a', 1, 'b', 2 , 'c', 3, 'd', 4).sort.perl;
  ["a", "b", "c", 1, 2, 3, 4, "d"]

After tracking it down a bit -- it's not clear what
infix: should do when given arguments of differing
types.  S03:2855 says:

Binary C is no longer the comparison operator that
forces stringification.  Use the C operator for the old Perl 5
C semantics.  The C is just like the C above except that
instead of returning C or C values it always
returns C, C, or C
(which numerify to -1, 0, or +1).

So, since C is just like C, here's the definition of C
for immutable types (S03:2829):

Binary C tests equality much like C<===> does, but does
so with "snapshot" semantics rather than "eternal" semantics.  For
top-level components of your value that are of immutable types, C
is identical in behavior to C<===>. 

And if we look at C<===>, we have (S03:2802):

Binary C<===> tests immutable type and value correspondence:
for two value types (that is, immutable types), tests whether
they are the same value (eg. C<1 === 1>); [...]
Two values are never equivalent unless they are of exactly
the same type.

This means that C< 3 === '3' > would be false, and
since C is identical to C<===> for immutable types,
C< 3 eqv '3' > would also be false.

But what to do with something like C< 3 cmp '3' >, or any 
infix: where the operands are of differing types?
Unlike C and C<===> that can simply return false for 
arguments of different types, C wants to return an
ordering.  Do we constrain C to only work on similarly-typed
operands (in which case my sort above would fail), or am I 
overlooking something obvious?

Pm

Re: Logo considerations - 3 logos needed

[Patrick R. Michaud]

On Wed, Mar 25, 2009 at 10:36:56AM -0400, Mark J. Reed wrote:
> Rakudo is a particular implementation of Perl 6 using Parrot.  While
> it is a separate project from both Perl 6 and Parrot, it is intimately
> tied to both, and I think its logo should reflect that. I don't see
> much point in having separate logos for "Rakudo on Parrot" and "Rakudo
> without Parrot".  I mean, I suppose much of the frontend work could be
> ported to a different backend, but would that still be considered
> Rakudo?

I don't know that I consider Rakudo Perl to be forever tied to Parrot.
If we come up with other backends, I'd still consider the result
"Rakudo"; similar to how "Pugs" referred to all of the various backends
available to it and not just the Haskell backend.

So from that perspective, I don't know that the Rakudo logo ought
to be strongly tied to Parrot, any more than we tie the Parrot logo
to the various GNU tools used to build it.

Pm

Re: Logo considerations

[Patrick R. Michaud]

On Tue, Mar 24, 2009 at 10:24:47AM -0700, Larry Wall wrote:
> I want something
> with gut appeal on the order of Tux.  In particular I want a logo
> for Perl 6 that is:
> 
> Fun
> Cool
> Cute
> Named
> Lively
> Punable
> [...]

+2 to this approach.

Pm

Rakudo Perl development release #15 ("Oslo")

[Patrick R. Michaud]

On behalf of the Rakudo development team, I'm pleased to announce
the March 2009 development release of Rakudo Perl #15 "Oslo".
Rakudo is an implementation of Perl 6 on the Parrot Virtual Machine [1].
The tarball for the March 2009 release is available from

http://www.pmichaud.com/perl6/rakudo-2009-03.tar.gz

However, because of the rapid pace of Rakudo development and addition
of new features, we still recommend that people wanting to use or work
with Rakudo obtain the latest version directly from the main repository
at github -- more on this in a bit.

Rakudo Perl follows a monthly release cycle, with each release code named 
after a Perl Mongers group.  This release is named "Oslo" in honor of 
the organizers of the 2009 Nordic Perl Workshop [2], April 16-17, 2009.  
The 2009 Nordic Perl Workshop will have a special focus on Perl 6, 
Rakudo Perl, and Parrot, including Perl 6 tutorials and hackathons 
after the conference itself.

A list of the other planned release dates and codenames for 2009 is 
available in the "docs/release_guide.pod" file.  In general, Rakudo 
development releases are scheduled to occur two days after each 
Parrot monthly release.  Parrot releases the third Tuesday of each month.

Rakudo Perl now uses git [3] for its version control system, hosted 
at http://github.com/rakudo/rakudo .  The README file there is kept 
up-to-date with the latest instructions for obtaining and building 
Rakudo Perl.

In this release of Rakudo Perl, we've made the following major changes
and improvements:

* Rakudo is now passing 7273 spectests.  This is an increase of 197 
  passing tests since the February 2009 release.

* The eval() construct now understands lexical variables from an
  outer scope.

* More of the builtin functions ("settings") are being written in Perl 6.

* Rakudo supports the "R" (reverse) metaoperator.

* Parsing of if, unless, while, until, etc. statements after blocks
  now works correctly.

* The Q quote operator is now implemented, along with several adverbial
  forms.  In particular, the Q:PIR form allows inline PIR to be
  included in Perl 6 code.

* Multi-method dispatch now works with inheritance also.

The development team thanks all of our contributors and sponsors for
making Rakudo Perl possible.  The next release of Rakudo (#16) is
scheduled for April 23, 2009.


References:
[1]  Parrot, http://parrot.org/
[2]  Nordic Perl Workshop 2009, http://www.perlworkshop.no/npw2009/
[3]  Git version control system, http://git-scm.org/

Re: r25745 - docs/Perl6/Spec

[Patrick R. Michaud]

On Mon, Mar 09, 2009 at 10:53:12AM -0700, Larry Wall wrote:
> : - PGE doesn't implement  by default, because that's not (yet?)
> :   part of the spec.  It only appears in PCT::Grammar, for people
> :   using the Parrot Compiler Toolkit to create languages.
> 
> I have wanted  a number of times, particularly after generic
> tokens that might or might end in \w.  So feel free to spec it.

Now done in r25767.  I went ahead and removed  and fixed
up the , , , and  descriptions while I was
at it.

Pm

Re: r25745 - docs/Perl6/Spec

[Patrick R. Michaud]

On Mon, Mar 09, 2009 at 10:32:02AM -0700, jerry gay wrote:
> > To make things a bit quicker for people writing custom versions of
> >  (which may need to include "comment whitespace"), the Parrot
> > Compiler Toolkit also provides an optimized  rule that matches
> > only between a pair of word characters.  Then the default definition
> > of  becomes
> >
> >    token ws {  \s* }
>
> if you need a mnemonic to help you remember what 'ww' means, use 'within 
> word'.
> 
> this reminds me that pge's  may be incorrect in its treatment of
> .  these characters (<['-]> by default) are word
> characters, but i don't think that's been tested, and i don't think
> it's been implemented, either.

A couple of clarifications:

- PGE doesn't implement  by default, because that's not (yet?)
  part of the spec.  It only appears in PCT::Grammar, for people
  using the Parrot Compiler Toolkit to create languages.

- AFAICT, apostrophe and hyphen are not yet "word characters" in
  the sense of being members of \w .  That is, they're considered
  to be valid in identifiers, but only when they are immediately
  preceded by a word character and immediately followed by an 
  alphabetic character.  Otherwise they're not part of the
  identifier.  (At least, that's how the current STD.pm reads.)

Pm

Re: r25745 - docs/Perl6/Spec

[Patrick R. Michaud]

> On Sun, Mar 08, 2009 at 09:43:17AM +0100, pugs-comm...@feather.perl6.nl wrote:
> =item * ws
> 
> Match whitespace between tokens.
> 
> =item * space
> 
> Match a single whitespace character. Hence C<  > is equivalent to C< 
> + >.


The definitions of  and  above are incorrect, or at least
misleading.   matches required whitespace between pairs of word
characters; it's optional whitespace otherwise.  The default definition
of  is something like:

token ws {|| \s* }

It's certainly _not_ the case that  is equivalent to + .

To make things a bit quicker for people writing custom versions of
 (which may need to include "comment whitespace"), the Parrot
Compiler Toolkit also provides an optimized  rule that matches 
only between a pair of word characters.  Then the default definition 
of  becomes 

token ws {  \s* }

Grammars can change this to things like:

token ws {  [ \s+ || '#' \h* \n ]* }

Pm