Squeak-dev September 2008

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120 participants
118 discussions

Object browser with behaviors?
by itsme213 05 Sep '08

05 Sep '08

Is there an object browser/inspector/explorer that will show me available methods on the object being browsed, in addition to its state? Thanks - Sophie

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What is internalName in the debugMenu
by stephane ducasse 04 Sep '08

04 Sep '08

Hi guys I would like to understand what is the use of the internal name in the debug menu when inspect a morph. Does anybody know? I played with that but it just renamed an instance variable. Stef

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Using V8 for other languages
by David Griswold 04 Sep '08

04 Sep '08

A little more info on V8. I talked briefly with Lars Bak and Robert Griesemer today, (both are on the V8 team, and Lars is the lead) and got a little bit of their perspective on using V8 for other languages. As was to be expected, the VM is targeted to JavaScript semantics, and given the gnarliness of those semantics, there are a few caveats to think about. - V8 will get faster as it matures, of course, however: - There will be issues around things like immediate object semantics, which don't exactly match up with any other language. Yucky JavaScript! - A bigger long-term performance issue is that given the dynamic nature of JavaScript objects (i.e. adding/removing slots on the fly) there apparently isn't any way around adding an additional indirection to deal with the object size changing dynamically. That is something that will just have to be lived with. I was hoping they had some magic there, but apparently not. I'm sure that these sorts of things can be worked around, but they do mean that V8 will never in its pure form quite reach the pinnacle of theoretical performance possible for a VM targeted specifically to Smalltalk etc. So it won't be as fast as Strongtalk, although it may get fairly close to VisualWorks performance. Nonetheless, I still think it or some derivative will quickly become the dominant dynamic language VM, for the following reasons: - Given who the developers are, and with Google behind it, it will be the fastest JavaScript VM for a long time to come. - For the same reason, it will be reliable and secure (as much as it can be, anyway; nothing is perfect). - It will be supported on the three major platforms (Windows, Linux, Mac). - It can be used with other browsers, so I'm sure it will be ported to Firefox (if only as an option). Some or all of the other browsers may also adopt it, given that it will have a very hard-to-overcome performance advantage (these sorts of VMs can't be pulled out of a hat). Although MS and maybe Safari may have too much of a Not Invented Here problem with it, as well as standards war issues. - those things, plus the other architectural advantages it brings, will make it a primary target for serious web app development, esp. Google apps. - So it will be ubiquitous So it will be an irresistible platform for other dynamic languages, even if they could theoretically run a bit faster on a custom VM. Remember it will still be a lot easier to run other dynamic languages on JavaScript than it is to run them on Java, since at least JavaScript is fully dynamic, unlike Java. And remember, the bottom line is that it is a clean, supported, state-of-the-art multi-threaded design that is fully open-source. So as a last resort, there is always FORK! -Dave

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MacOSX VM
by Bergel, Alexandre 04 Sep '08

04 Sep '08

Dear List, I try to run the OSX VM from the command line. I run the following command, where ready.image is a Squeak image: /Users/alexandrebergel/Desktop/Smalltalk/Squeak/Squeak\ 3.8.12beta4U.app/Contents/MacOS/Squeak\ VM\ Opt ready.image A mac file browser opens and apparently is waiting for me to select an image. The image is not run therefore. This is strange since I provided the name of one. Any idea how to launch a Squeak from the command line using the Squeak 3.8.12beta4U VM? Shall I use the linux VM instead? I get the following message instead: -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 2008-09-03 17:33:19.955 Squeak VM Opt[3146:10b] NSDocumentController Info.plist warning: The values of CFBundleTypeRole entries must be 'Editor', 'Viewer', 'None', or 'Shell'. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Cheers, Alexandre -- _,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;: Alexandre Bergel http://www.bergel.eu ^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;.

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migrating some traits usage - a question
by itsme213 04 Sep '08

04 Sep '08

I have some Squeak code that I want to try out in Gemstone. My squeak code uses traits, Gemstone does not support traits. Since (a) I am not doing fancy trait stuff, and (b) I want to keep a trait-like separation in my code, and (c) I want to use Monticello to ferry between squeak and gemstone, I was going to: - replace each trait with a corresponding class - simply copy all trait methods to appropriate classes when needed - put a "TRAIT METHOD - DON'T EDIT" comment in the methods :-) Any glaring problems in the approach below? Better solutions? How do I control which method-category these are copied into? Class>> allMethodsUpto: aSuperClass injectInto: traitUser self methodDictionary keysAndValuesDo: [ :k :v | traitUser addSelector: k withMethod: v ]. (self superclass ~= aSuperClass) ifTrue: [ self superclass allMethodsUpto: aSuperClass injectInto: traitUser ] ... elsewhere I know which (normal) class uses which (trait) class: (self classesUsingTrait: trait) do: [ :traitUser | trait allMethodsUpto: Object injectInto: traitUser ]. Many thanks - Sophie p.s. It would be great if there was a more portable implementation of trait-like functionality.

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Squeak leadership meeting minutes 2008-09-03
by Craig Latta 03 Sep '08

03 Sep '08

Squeak board meeting minutes, 2008-09-03: present: craig, randal, bert absent: dan, tim, igor, yoshiki - Web team is in process, with a beta already available announced on the IRC channel. - Craig got several new signed contributor agreements from Viewpoints. -C

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C to get closures
by Todd Blanchard 03 Sep '08

03 Sep '08

I thought this was interesting. Development of closures for C (and ObjectiveC). http://lists.cs.uiuc.edu/pipermail/cfe-dev/2008-August/002670.html Until there is more real documentation, this is a basic idea of Blocks: it is closures for C. It lets you pass around units of computation that can be executed later. For example: void call_a_block(void (^blockptr)(int)) { blockptr(4); } void test() { int X = ... call_a_block(^(int y){ print(X+y); }); // references stack var snapshot call_a_block(^(int y){ print(y*y); }); } In this example, when the first block is formed, it snapshots the value of X into the block and builds a small structure on the stack. Passing the block pointer down to call_a_block passes a pointer to this stack object. Invoking a block (with function call syntax) loads the relevant info out of the struct and calls it. call_a_block can obviously be passed different blocks as long as they have the same type. From a technical perspective, blocks fit into C in a couple places: 1) a new declaration type (the caret) which work very much like a magic kind of pointer that can only point to function types. 2) block literals, which capture the computation 3) a new storage class __block 4) a really tiny runtime library. The new storage class comes into play when you want to get mutable access to variables on the stack. Basically you can mark an otherwise- auto variable with __block (which is currently a macro that expands to an attribute), for example: void test() { int X = ... __block int Y = ... ^{ X = 4; }; // error, can't modify a const snapshot. ^{ Y = 4; }; // ok! } From the implementation standpoint, roughly the address of a __block object is captured by the block instead of its value. The is tricky though because blocks are on the stack, and you may want to refer to some computation (and its __block captured variables) after the function returns. To do this, we have a simple form of reference counting to manage the lifetimes of these. For example, in this case: void (^P)(int); // global var void gets_a_block(void (^blockptr)(int)) { P = blockptr; } void called_sometime_later() { P(4); } if gets_a_block is called with a block on the stack, and called_sometime_later is called after that stack frame is popped, badness happens (yay for C!). Instead, we use: void (^P)(int); // global var void gets_a_block(void (^blockptr)(int)) { P = _Block_copy(blockptr); // copies to heap if on the stack with refcount +1, otherwise increments refcount. } void called_sometime_later() { P(4); _Block_release(P); // decrements refcount. P = 0; } The semantics of this is that it copies the block off the stack *as well as any __block variables it references*, and the shared __block variables are themselves freed when all referencing blocks go away. The really tiny runtime library implements things like _Block_copy and friends. Other interesting things are that the blocks themselves do limited/ optional type inference of the result type: foo(^int(){ return 4; }); // takes nothing, returns int. foo(^(){ return 4; }); // same thing, inferred to return int.

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Box-Admins Team Report for August, 2008
by Ken Causey 03 Sep '08

03 Sep '08

The box-admins team is reponsible for seeing that the community shared server is maintained and setting up any new features to be hosted on that server. For August, 2008: Late in the month the community server went down for a period of less than a day. This is the second time the server has stopped working in the last 45 days. I was unable to find any evidence in the logs as to what may have happened this time. It seems in July a fan failed. It has been approximately 3 years since we provisioned this server with Hetzner. For a while now we have been sitting at around 90% diskspace usage. While the need is not immediate, I believe we should plan on provisioning a replacement server sometime in the next year. In other news the Leadership team finalized a decision on Janko Mivsek's proposal for a new www.squeak.org website based on Swazoo/AIDA/Scribo. I'll let him provide more detail but the new site should be available soon. Over the last couple of months I and Matthew Fulmer have been doing some cleanup on the Squeakmap (http://map.squeak.org/) map (or database). We identified on the order of 80-100 packages whose latest release was not currently downloadable. We've been working on those along with the package maintainers to improve the utility of Squeakmap. Work on that front continue and I hope to have a more detailed report on this work soon. I want to thank the community for the monetary support needed to fund the box and remind them that the bills continue to appear and that you can currently contribute to the hosting bills by going to http://www.squeak.org/Foundation/SupportSqueak/ and purchasing a Squeak badge. Note that a donation here may be used for other Squeak Foundation services including but not limited to development, development infrastructure, and promotion of Squeak. The services being hosted have continued to grow and include (but are not limited to): http://www.squeak.org/ SqueakMap - http://map.squeak.org/ http://ftp.squeak.org/ http://lists.squeakfoundation.org/ http://discuss.squeakfoundation.org/ http://source.squeakfoundation.org/ http://map.squeak.org/ https://svn.squeak.org/ http://update.squeakfoundation.org/ http://wiki.squeak.org/ http://bugs.squeak.org/ and DNS services for squeak.org and squeakfoundation.org domain names. Ken

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Re: [squeak-dev] Fwd: Chrome and V8
by Igor Stasenko 03 Sep '08

03 Sep '08

2008/9/3 Dan Ingalls <Dan(a)squeakland.org>: > Avi wrote... > >>I've built this on Mac OS X and from some very simple >>micro-benchmarks, I'd guess its performance is on par with >>VisualWorks. Very cool. > > Yes, "on a par". Looks like 2-3x Squeak, but half of VW. > > It's definitely a real vehicle, and the crew behind it understands modularity, processing and, should it ever be necessary, last-inch optimization. > > Fun times! http://code.google.com/apis/v8/run.html FireFox - Score: 218 Chrome - Score: 1984 would be interesting to implement these benchs in smalltalk , and run over Squeak & VW > > - Dan > > -- Best regards, Igor Stasenko AKA sig.

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Fwd: Chrome and V8
by John M McIntosh 03 Sep '08

03 Sep '08

---------- Forwarded message ---------- From: Dave Griswold <David.Griswold.256(a)gmail.com> Date: Tue, 2 Sep 2008 12:14:32 -0700 (PDT) Subject: Chrome and V8 To: Strongtalk-general <strongtalk-general(a)googlegroups.com> Hi everyone, It's been a while, but now that Google has announced Chrome and V8, I can finally make a little clearer a major reason why I haven't been pushing Strongtalk development for quite a while: Chrome's new JavaScript engine V8. The V8 development team has multiple members of the original Animorphic team; it is headed by Lars Bak, who was the technical lead for both Strongtalk and the HotSpot Java VM (as well as a huge contributor to the original Self VM). I think that you will find that V8 has a lot of the creamy goodness of the Strongtalk and Self VMs, with many big architectural improvements: * open source * will run (eventually) on Windows, Linux, and Mac * dynamically JITs to native code * can run completely independently from the browser * generates hidden classes behind the scenes, since javascript doesn't have them (very reminiscent of the 'maps' used in the Self VM). * is multi-threaded from the ground up, with the ability to share VM overhead between different OS processes. * has even smaller object headers than in Strongtalk, making small object overhead even smaller * kick-ass compacting, non-conservative garbage collector The really big deal here is the fundamentally multi-threaded, multi- process nature of the VM. That is something that we don't really have the ability to just hack into the Strongtalk VM; it would involve practically an entire rewrite. Plus, expect a lot of architectural improvements in the source code based on experience with Self, Strongtalk and Java Hotspot VMs. I think these properties will rapidly make V8 the dominant VM for dynamic languages. It ought to make a great platform for Smalltalk. Since I am not a Googler, and they are so secretive, I am not yet privy to all the gory details, but I suspect that it probably won't use type-feedback like Strongtalk, which would be the one big negative (and would mean that it wouldn't be as fast as Strongtalk). However I don't know that for sure, and in any case it will be open source, which means that it might be a nice platform to add type-feedback- based inlining to if they don't do it. At any rate, it *does* JIT to native code, so it will be far faster than Squeak, and probably a lot faster than Visualworks as well. We'll have to see what the details are when the code comes out, but the release of the V8 VM is the beginning of a whole new era for dynamic languages (Smalltalk, Ruby, Python, etc). Let the flood of fast new dynamic language implementations begin! --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Strongtalk-general" group. To post to this group, send email to strongtalk-general(a)googlegroups.com To unsubscribe from this group, send email to strongtalk-general+unsubscribe(a)googlegroups.com For more options, visit this group at http://groups.google.com/group/strongtalk-general?hl=en -~----------~----~----~----~------~----~------~--~---

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