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Perl 6 has three code placeholder operators, known affectionately as the "yada, yada, yada" operator (see List Prefix Precedence in Synopsis 3). It's a matter of (very sarcastic) public record how much I love writing, maintaining, and patching parsers, so I've just sent a very preliminary five-line patch to p5p to add support for ... to Perl 5.
--- perly.y~ 2008-05-09 17:47:35.000000000 -0700
+++ perly.y 2008-05-09 17:47:41.000000000 -0700
@@ -1227,6 +1227,11 @@
}
| WORD
| listop
+ | DOTDOT
+ {
+ $$ = newUNOP(OP_DIE, 0,
+ newSVOP(OP_CONST, 0, newSVpvs("Unimplemented")))
+ }
;
/* "my" declarations, with optional attributes */
Apply this to recentish bleadperl sources, run perl regen_perly.pl, rebuild, and now you can run programs such as:
sub foo { ... }
foo();
And get an "Unimplemented at file line line." error message.
(Now everyone who complains that I don't code enough to match my talk, please punch yourself in the face.)
The Perl 6 design team met by phone on 07 May 2008. Larry, Allison, Patrick, Will, Jerry, Nicholas, Jesse, and chromatic attended.
Allison:
c:
Allison:
c:
Patrick:
c:
Jesse:
Larry:
nofat rulePatrick:
Jerry:
Patrick:
Jerry:
c:
Nicholas:
state implementation of any languageJesse:
Patrick:
Jesse:
Nicholas:
Jesse:
Will:
Jerry:
Patrick:
Nicholas:
Jerry:
Jesse:
Nicholas:
Allison:
Jesse:
Allison:
Will:
Patrick:
Allison:
Will:
Allison:
Jerry:
Patrick:
Will:
Patrick:
Jerry:
Patrick:
Larry:
Patrick:
Larry:
c:
Will:
Jesse:
Parrot r27355 was fun to write.
One of the persistent error messages Parrot emits for compiler writers is
Null PMC access in invoke(). If you've had your hands deep in the
guts of Parrot, you know what that means -- you tried to call a Sub PMC when
you don't have a Sub PMC, you have no PMC. (If you don't know what that means,
this entry is for you.)
Sometimes this means that there's a problem in Parrot. We've fixed almost all of those problems though, so the error usually comes from elsewhere. If you're writing a compiler, or running a compiler built on Parrot, the error usually means "You tried to call a function that doesn't exist."
Parrot's optimizer does something interesting at the end of compilation time. You've probably heard that Parrot's compiler, IMCC, translates PIR into PBC. That is, it turns source code into bytecode, which Parrot can either serialize t to disk or execute immediately. That bytecode is just a chunk of linear data in memory. It's not really a data structure. (Okay, it's a C array, but that doesn't make it a data structure.)
After IMCC has finished building a standalone chunk of bytecode, it performs a constant fixup phase. The notable part of this phase is that it edits the bytecode in place to replace all named invocations of functions known at fixup time with offset invocations.
The previous code looks something like:
invoke known_function
null # padding
null # padding
If IMCC has already seen known_function by this time, the
direct invocation of known_function can continue. There's no
runtime lookup necessary; all functions already compiled and ready are
available in the bytecode.
If IMCC hasn't seen that function, runtime lookup is necessary, and so this function replaces the bytecode earlier with the equivalent of:
.local pmc func
func = find_name 'unknown_function'
invoke func
(I've simplified what actually happens slightly, because the concepts are more important than the details. Hopefully you see why the padding is necessary. If not, just imagine trying to splice additional opcodes into what may presumably be a lengthy C array -- like I said, barely a data structure.)
The problem with this second form occurs when find_name returns
a NULL PMC, which it can legitimately do. In that case, the
invoke opcode tries to invoke a NULL PMC and fails, and Parrot
throws an exception saying "There's nothing here to invoke." There's the error
message.
It's clear why that happens, but it's not useful. It would be more
useful to see the name of the function you tried to invoke in the
error message. Unfortunately, by the time Parrot calls the invoke
op, that name is long gone.
My first idea was to rewrite the dynamic lookup form into something resembling:
.local pmc func
func = find_name 'unknown_function'
if defined func goto call_it
die "Can't invoke 'unknown_function'"
call_it:
invoke func
Unfortunately, I didn't have the space in the bytecode stream to insert that many ops, and I had no desire to move chunks of memory around in that C array. I could have added more padding after an invocation, but to be fair I'm only mostly sure that it exists there in the first place.
I had room for one op with a destination PMC and a string constant argument.
I added an experimental op called find_sub_not_null which does the
same thing as find_name but throws an exception which includes
the requested name if Parrot can't find a PMC of that name.
This isn't entirely an ideal situation. It's a special case op, and I prefer to remove ops where possible. It's also nearly code duplication, though it's effectively three lines of code in an op, which isn't awful. I still want to be able to perform these kinds of transformations in PBC itself, but we need a different way to generate PBC and perform op-level transformations in PIR before we can do this effectively.
There are always tradeoffs, though. Doing this check in C is slightly faster than doing it in PIR. The standard Perl 5 rule of optimization applies even in Parrot -- the fewer ops, the mostly faster you can go. As well, I was able to improve the warning message today, rather than at some point in the future when we have better PBC optimization possibilities.
After all, I can always remove this op in the future.
I started out the day by looking through the RT queue for Rakudo. Two tickets were already dealt with, so I just closed those. Another was a bug report concerning assigning undef to typed variables. Doing:
my Int $x = undef;
Would give a type check failure. This is now resolved. Furthermore, if your type is a class name, then assigning undef at any point to it will result in it holding the protoobject for that class again. I also took a moment to post to Perl 6 Language to get some clarifications on what "my TypeName $x;" left $x being when $x was a role, subset type or a junction of types.
Last week I started getting grammars in place. I got so far as having the regex live in the correct namespaces, but that didn't make grammars at all class-like, which is how they should be. This week I set out to fix that. Grammars now get protoobjects too, which you can call .WHAT and so forth on. Furthermore, I got inheritance working and also smart-matching against a grammar, which runs it's TOP rule. Therefore you can now run the following example in Rakudo.
grammar Loads { regex Lots { \d+s } };
grammar Many is Loads { rule TOP { <Lots> of <Lots> } };
if "100s of 1000s" ~~ Many {
say $/; # 100s of 1000s
}
Having closed four RT tickets so far, I took a look through there to see what else there was. There was one that did most of what was needed to implement the .perl method on Junctions (which you can call, in theory anyway, on anything to get a Perl representation of it). I did the required fixes and applied it, but realized in the process that we were missing .perl for any of the really fundamental types, so I added it for Num, Int and Str.
With that done, I spent a little time on the S12 tests. I added fudge directives to get one of the that failed to parse to do so, and added an extra test. I plan to add much more here and flesh out the tests quite a bit over time.
Turning back to the OO support, I did some updates to the grammar that both brought us closer to STD.pm - the official grammar - and added the ability to parse a range of extra things. The first grammar changes were related to method calling. Normally you call a method just with ".", but private methods are called with "!". Additionally, there are ways to call sets of methods with quantifiers (.?, .+ and .*, with meanings analogous to those in regexes). Finally, I added the ability to scope declarations of routines too, so we can now parse lexical subs and private methods. I stubbed in conditionals for all of these cases that throw unimplemented exceptions, so people didn't use them expecting that because they parse, they will also work.
So, now there's a bunch of stubs in there for another bunch of OO features and, if nobody beats me to it, I'll be filling some of those out on my next Rakudo day, or maybe before then if time allows (though I'm moving apartment - and country - over the coming week, so I'm not expecting to have much time). A big thanks to Vienna.pm for funding today's work.
For years, I've thought that the only thing sillier than complaining about disaffection and how the world really should work differently in IRC was to sign silly Internet petitions about it. Now I realize that people who feel compelled to register their righteous indignation in 141 characters of chatspeak matter least.
Here's a quarter, kid. Go buy a postcard.
Today's work has been a mixture of refactoring and clean-ups that had been on the want list for a while, but just hadn't happened, as well as making some new things work.
First, the initial work I did on types attached them to variables, but what we really needed was a more general way to attach properties. Therefore, there is now a hash of properties instead, where we can stash other stuff.
Next up, I had based pairs on the Parrot Pair PMC, though as Patrick pointed out it's so far off being right for Perl 6 (for example, it's mutable, the Perl 6 one isn't) that we might as well just have our own. Dropping the Parrot Pair PMC and doing that took me all of ten minutes of work, and we get the semantics of pairs a bit more correct too. So that's much cleaner now.
A few days back, dakkar sent in a bug report regarding inheritance. It was almost correct code, but didn't work on Rakudo, since initialization of parent attributes was not yet implemented. I've now implemented this, and I'll borrow the example from the bug report to demonstrate it.
class Foo {
has $.x;
method boo { say $.x }
}
class Bar is Foo {
method set($v) { $.x = $v }
}
my Foo $u .= new(:x(5));
$u.boo; # 5
$u= Bar.new(Foo{ :x(12) }); # This is what now works
$u.boo; # 12
$u.set(9);
$u.boo; # 9
This is not some magical hacky syntax just to make constructors work; you can use it in the general case to associate some vivification data with a proto-object, which gives you a copy of it back with the data attached. It's a bit like currying the object instantiation. So after making the above work, it wasn't much more work to get the following working.
class Foo { has $.x }
my $foo42 = Foo{ :x(42) };
my $test = $foo42.new();
say $test.x; # 42
Note that the original Foo itself isn't changed. We'll have to revisit this again later, because the way I've done it now doesn't have the lazy semantics it's eventually meant to have. It makes the common use case work, though.
With some time spent on objects, I moved onto some improvements to regex stuff. The upshot of this is that you can now use grammar to group regexes into a namespace.
grammar Test {
regex Load { \d+s };
rule Loads { <Load> of <Load> };
}
if "100s of 1000s" ~~ Test::Loads { say "yes" }
yes
Note that this is just the start of grammars; inheritance doesn't yet work and you can't smart-match against them yet. It's a stop forward, though.
If you're an avid Rakudo follower, you'll have noted that regex, rule and token all (wrongly) did the same thing before today. I've fixed that too now (there was some behind the scenes work in being able to pass options to the compiler that will be useful elsewhere, as to users of the Parrot Compiler Toolkit in general). In a nutshell, token and rule don't backtrack, where as regex does, and additionally rule translates spaces to the rule, whereas normally they have no effect on the match.
# Demonstrating :ratchet semantics (rule like token here).
regex WillBT { a*a }
token WontBT { a*a }
if "aaa" ~~ WillBT { say "yes" } else { say "no" }
yes
if "aaa" ~~ WontBT { say "yes" } else { say "no" }
no
# Demonstrating :sigspace semantics.
regex Test1 { \d \d };
rule Test2 { \d \d };
if "12" ~~ Test1 { say "yes" } else { say "no" }
yes
if "1 2" ~~ Test1 { say "yes" } else { say "no" }
no
if "12" ~~ Test2 { say "yes" } else { say "no" }
no
if "1 2" ~~ Test2 { say "yes" } else { say "no" }
yes
So, that's what got done today. I'd like to thank Vienna.pm for funding this work, and hope you'll have fun playing with it, breaking it and reporting bugs. :-)
Eclectus is a Scheme-compiler implemented in Scheme. The compilation target is a Parrot Abstract Syntax Tree, which is being run with the help of the Parrot Compiler Toolkit.
A sideline in Eclectus is the the problem how to tell PCT about the PAST generated in Scheme. Up to now I generated PIR that built up that data structure. This involved nasty dealings with unique ids for Parrot registers.
Generating NQP is much saner. The PAST is now set up with nested PAST::Node constructors.
Even nicer would be to create a YAML representation of PAST. But PCT doesn't support this yet.
First of all, before I dig into what my recent Rakudo hackings have been, I'd like to thank Vienna.pm for funding me to work on Rakudo. I will be working one full day a week on Rakudo from now on, at least for the next three months and, hopefully, longer. Today is the first day I'm working under this funding, so I'll be posting again later on today about what I got done. This post is just to update you on little bits that I've been doing, but didn't get written up yet.
First of all, you can now use the .= operator.
class Foo { }
my Foo $x .= new();
Here we call the 'new' method on $x, which we know is of type Foo thanks to the type declaration, and assign what it returns - namely, an instance of Foo - to $x. I did initially put this in a while ago, but it was a tad buggy and I wanted to get those worked out before posting it. That's been done, so happy playing. (And note you can use it in places other than declarations too.)
Additionally, some very basic multi-method dispatch based upon types is now in place. You can only use class names, not constraints or role names at the moment for the types, and certainly not more complex types than that. However, it's a start and allows us to run the following example.
class Thing {}
class Rock is Thing {}
class Paper is Thing {}
class Scissors is Thing {}
multi sub defeats(Thing $t1, Thing $t2) { 0 };
multi sub defeats(Paper $t1, Rock $t2) { 1 };
multi sub defeats(Rock $t1, Scissors $t2) { 1 };
multi sub defeats(Scissors $t1, Paper $t2) { 1 };
my $paper = Paper.new;
my $rock = Rock.new;
say defeats($paper, $rock); # 1
say defeats($rock, $paper); # 0
Finally, I put in a small optimization to avoid having to run some runtime type-checks when we can statically determine they're not needed. This should help performance a little.
Every so often someone reports weird behavior in #parrot, and someone says "Hey, that looks like a GC bug!"
Most of them aren't. (Most of them lately seem to be that we're changing the way bytecode works, and we don't have all of the dependencies for all of the generated PBC files correct, so you have to run make realclean and rebuild.)
While adding the vtable override cache the other day, I did create a forehead-slapper of GC bug, but I caught it before I checked in the code. How did I know it was a GC bug? Easy.
The Class PMC itself contains pointers to several other PMCs and GC entities, including the name of the class and its corresponding namespace. I added a pointer to a Hash PMC which maps the names of vtable overrides to Sub PMCs.
I remember thinking at the time "Hey, it's just a cache. I don't have to mark it during the mark phase explicitly. All of the Subs it refers to will stay alive as long as their namespaces live. That's easy."
When I ran the tests, I saw a weird error about not being able to perform a
keyed index PMC lookup on a Key PMC. I set a breakpoint on the
real_exception function (which reports these kinds of errors) in
the debugger, and the backtrace showed that the cause of the call was my cache
lookup function.
"That's weird," I thought. Then I realized what I had done.
My line of thinking was correct in that I don't have to mark all of the PMCs contained in the cache PMC. They're already reachable from the rootset through the namespace. The GC won't collect them.
The problem is that the cache itself -- the Hash PMC -- is only reachable through the Class PMC. Unless it gets marked as live, the GC will reclaim its header and put it on the free list again.
The Class PMC still has a pointer to that header, but the next PMC allocated from the GC which uses that header will overwrite the PMC's information, effectively morphing my lovely cache into something else. In this case, my Hash PMC turned into a Key PMC.
Usually they're not this obvious, but I've gone through all of the PMCs in Parrot to make sure they mark their contained GCable entities appropriately.
The Perl 6 design team met by phone on 23 April 2008. Larry, Allison, Patrick, Jerry, Will, Jesse, Nicholas, and chromatic attended.
Jerry:
Patrick:
Jerry:
Nicholas:
Jesse:
Jerry:
Larry:
Jerry:
Larry:
Allison:
Patrick:
Allison:
Patrick:
Will:
Allison:
Will:
c:
Patrick:
c:
Jesse:
Patrick:
c:
Patrick:
Will:
c:
Patrick:
Will:
Nicholas:
c:
Jesse:
c:
Jesse:
c:
Jerry:
return Allison:
Will:
return, break, and continue Allison:
Patrick:
return type exception, it grabs the arguments, does what it has to, and then does a Parrot returnAllison:
Patrick:
handled Allison:
Patrick:
return in for the April 15 milestone we're behind onJerry:
Allison:
c:
Allison:
A lot of people complain about reference counting as a memory management strategy in Perl 5, and they have a point. Unless you're very careful, reference counting spreads its tendrils throughout your system. Unless you're very disciplined, you'll forget to increase a reference count somewhere, and you'll end up collecting things in the wrong places.
The paper A Unified Theory of Garbage Collection discusses the most popular modern GC strategies to demonstrate how reference counting and tracing garbage collection are roughly equivalent, especially as concerns about performance, correctness, and conservativeness increase.
I explain this because I added reference counting to a small part of Parrot today as an optimization -- 11.73% on my Rakudo-building benchmark.
Parrot has an internal data structure called a stack. This represents a particular environment within the call graph. If you think of a normal program flow, where function A calls function B calls function C which returns to B and returns to A, you'll have a sense of a normal call stack. Parrot's stack is similar, except that we use continuation passing style (CPS), where it's not a stack, it's a graph, and control flow doesn't have to be that linear.
There's plenty of literature on CPS (including Luke Palmer's how
to get a free sandwich with continuations, but the important idea is that
function A sets a bookmark inside and passes that bookmark along to function B.
B does the same thing when it calls C. At any point, you can look up any
bookmark you happen to have and magically teleport (okay, it's just a jump
instruction in your processor -- someday I'll explain how very low level
languages have eval and very high level languages have
eval and it's just the poor jerks in the middle who can't do
anything useful without feeding the world's pointiest programming language into
their AbstractFactoryFactoryFactories) to the point of that bookmark.
Ranty story short, our stack is a mostly-acyclic graph represented as a linked list, and stack entries -- or chunks -- are garbage collectable entities.
If you've even sat next to one of my "Let's Make Parrot Go Faster!" entries on a bus somewhere, or heard it playing softly in an elevator, you know that one good way to make Parrot go faster is to use fewer garbage collectable entities. One way to make an O(2n) algorithm faster is to make it an O(log n) algorithm. Another way is to make n smaller, and that's easier for now, especially because all I have to do is watch over Andrew Whitworth who's going to write a nice new garbage collector and keep track of Senaka Fernando, who's going to connect the nice garbage collector from Apache Harmony into Parrot.
One nice feature of reference counting (ah, now you see the connection!) is that you can recycle dead objects as soon as you know they're dead. One sad misfeature of a conservative garbage collector is that dead bodies stack up for a while until you can mulch them. One horrible thing about a stop-the-world full mark-and-sweep garbage collector (and try to guess what Parrot has at the moment) is that if you're out of memory in one of the arenas you care about, you have to mark all of the living GCable entities in your system and sweep all of the pools in all of the arenas to find everything that's alive and to recycle everything that isn't.
If you want to go fast, you want to avoid this until it's absolutely necessary.
Here's the interesting thing about stack chunks: Parrot stores them in one
place in one function (stack_push) and unstores them in one place
in one function (stack_pop). Again, the names are really bad
because it's a graph and not a stack, but you get the point.
I noticed this when I profiled the Rakudo-building benchmark again and saw
that stack_push was one of the most expensive inclusive calls,
apart from the garbage collector. It calls a function which calls a function
which calls a function which asks for a new stack chunk from the GC. When
there are no more free stack chunks, the GC runs again, and that eats up
precious cycles.
After a few minutes of thinking, I realized that the
stack_push/stack_pop pair formed a boundary around a
stack chunk's lifespan. Popping a chunk off of the stack meant that nothing
else needed it. That chunk is immediately identifiably a dead object, suitable
for recycling.
Rather than waiting for a full GC run to find every live object in the system and then run across this dead object and recycle it, I added a couple of lines of code to recycle it automatically then and there.
There was my immediate 11.73% speedup.
There was also a problem in the Continuation PMC tests; I noticed this only after I patted myself on the back for moving the bottleneck in my benchmark elsewhere. I'm sure you'll see it if you think for a moment, especially about how I kept writing that the stack isn't a stack, it's a graph implemented as a linked list.
The problem is that there's not a single linked list. If you take a continuation at various points in the call graph, you can have several linked lists that all share the same tail. If you exhaust one of those call chains, you may pop a stack chunk that's part of another call graph elsewhere. Your reference to it goes away, but it's still live elsewhere, so if you recycle it then and there, you may end up reusing the chunk and storing inappropriate data in it while something else expects it to stay pristine.
If you're very clever, you've figured out the solution.
I added a reference count to the stack chunk structure, incremented it on
stack_push, decremented it on stack_pop, and recycled
the chunk in the latter function only if the refcount is zero.
Is this a long-term solution? Probably not; I posted my initial investigation to the parrot-porters list, and we had a nice discussion on alternate techniques. We'll have to refactor the code more heavily once we find a better approach, but for now, I'll live with this optimization.
(Seneca Cunningham found what appears to be a crash related to this, but I think I've found the culprit and fixed it by adding another reference count pair to the Continuation PMC. See? I told you reference counting made itself pervasive.)
I've long used part of the Rakudo-building process as my benchmark for Parrot optimizations. It doesn't exercise all of Parrot by any means, but it pushes the garbage collector, the string system, and the object system pretty hard. It's also the longest part of the build process anywhere, so improving performance there has a dramatic effect on productivity.
I've long known that it appends to and concatenates strings very frequently. The corresponding Parrot functions always show up near the top of the cost list from Callgrind. I've spent a few hours here and there trying to speed them up, but short of rethinking them entirely, I've never found a good solution.
We don't (yet) have a PIR-level profiler like Callgrind (but I'm working on it). Sometimes I can read through the code and see things that might be expensive, knowing what eventually gets called and where. On a whim, I browsed through the generated code for Rakudo to find concatenation. One idiom jumped out at me:
$S0 = concat "PIR", ':"'
This line of code catenates two constant strings into one, and assigns the result to the virtual string register $S0. It's not terribly inefficient; the two constant strings are in the constant table in the bytecode, so they don't get recreated on execution. However, the result is always going to be a constant string.
There's no reason the optimizer couldn't rewrite that line of code into:
$S0 = 'PIR:"'
It didn't. Now it does.
The optimizer already knew how to optimize away constant addition,
subtraction, and other math operations. All I had to do was tell the opcode
generator not to generate the concat_s_sc_sc op (concatenate two
string constants and put the results in a string register -- the destination
register always comes first in the argument list for an opcode), add the
concat operator to the list of rewritable three-register opcodes,
and add a case to the rewriter where the destination register is a string
register.
The result is a modest 5.5% speedup in my benchmark. Part of the gain is avoiding run-time concatenation, but part of it is also using fewer GCable entities. The less garbage you create, the less garbage you have to collect and the less frequently you have to collect it. 5.5% isn't a huge gain, but it's a step in the right direction. Every second we shave off of the hack-compile-test cycle is an improvement, and these optimizations help all Parrot programs as well.
(Are these entries interesting? I seem to get more feedback when I complain about various Technology Distortion Fields.)
Late last night, PerlJam posted in #parrot a small Perl 6 program which gave the wrong answer in Rakudo:
my $foo = 'fred';
say $foo;
$foo--;
my $bar = 'fred';
say $bar;
The correct output is obviously:
fred
fred
Rakudo gave:
fred
frec
PerlJam and Infinoid both correctly diagnosed the problem as a COW problem. What's that, and why does it matter?
The Rakudo compiler turns this code into PIR code. PIR is the native high level language of Parrot. Inside Parrot, the PIR compiler (IMCC) turns PIR into Parrot bytecode. As part of that process, IMCC identifies constant string literals and treats them specially.
Like the Perl 6 code, the PIR code produced by Rakudo contains the string literal fred twice. The PBC produced by IMCC doesn't; it refers to a single internal data structure twice.
This is usually the right approach. In this case, where the literal string appears twice and is only four characters long, there's little benefit, but in a complex program, you can save a lot of memory and time with judicious caching.
Now of course sometimes people want to mutate these strings. They're mutable; you can change them. That's where the COW comes in. It's like memory handling on a decent operating system. You only make a copy of the memory at the last possible point, where you know you're going to modify your copy. Parrot strings support this, so if you use Parrot operations directly, you don't even have to know that COW exists. It just works.
The problem was that the string modification took place outside of Parrot, in a custom Perl6Str PMC. Think of a PMC like a class which represents internal data structures, and you're most of the way to understanding them. The Perl6Str PMC has two operations, increment and decrement which do exactly what you'd expect to strings on the C level. This means that they modify the C string directly.
Because this occurs at the C level (working directly on C pointers), Parrot doesn't have a chance to perform the copy-on-write operation to the string, and the modification of one string produces the modification of all other strings which refer to the same string literal.
My first solution was to call the Parrot string function to perform the copy (because there's a write coming up) directly, but that made too much code move around (C89 and declarations before code, grr). Instead, I made a two-line macro which does an in-place copy and assign, and only two lines of code had to change to do the right thing. Now the code prints, as it should:
fred
fred
(I spent more time writing this entry than I did fixing the problem.)
This is complete vaporware. The constraints and software development link above is just annoying. There is no excuse for an 8 year long dev effort with no milestones or end in sight. We could have had a nice language by now with some simple features like parameter lists...but we're stuck with Perl 5 circa 1996 because some people got big useless ideas into their heads and hijacked what was once a useful technology and turned it into an obsolete pile of code about as valueable as awk or sed. The article should really begin to change, from a "whats new and cool in [Perl 6]" to "why [Perl 6] was such an utter failure". the [Perl 6] team has failed us all.
— Justforasecond, Personal Comments on the Perl 6 discussion page on Wikipedia
If my economics are wrong, show me. If my math is wrong, show me. If you know the secret to software development, show me. Here's zero dollars and the source code. Fix everything you can about Perl 5. See you in two years.
Here's 1084 patches I've made or applied to Parrot in the past three years. Not coincidentally, I've had actual Perl 6 code running in public for about the same amount of time. You can find it if you search the web. Of course, you can find Perl 6 and Parrot milestones if you search the web too.
P.S. Perl 5.10, circa 2007 is quite decent. Try upgrading to software released this millennium.
The Perl 6 design team met by phone on 16 April 2008. Larry, Allison, Jerry, Will, Nicholas, Jesse, and chromatic attended.
Jerry:
make release target is broken on Windows, and that's the only platform I had out herePatrick:
Will:
perl6 after that gets straightened out tooc:
Larry:
Jesse:
Jerry:
c:
Allison:
c:
Allison:
Jerry:
Allison:
Jerry:
c:
Will:
Jerry:
c:
config::* modulesParrot::Embed |
When you need perl, think perl.org
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