May 2010 - Pharo-dev - lists.pharo.org

[Pharo-project] [ANN] DTrace for Squeak/Pharo
by Adrian Lienhard May 12, 2010

May 12, 2010

Now there's also a DTrace provider for the Squeak VM: http://www.adrian-lienhard.ch/blog?dialog=smalltak-meets-dtrace DTrace is a powerful, kernel-based dynamic tracing framework. With the new provider one can analyze the execution of Pharo/Squeak applications. My post is an introduction that should get you quickly started. I've attached a pre-compiled VM for OS X. Hope you like it :) Cheers, Adrian ___________________ http://www.adrian-lienhard.ch/

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Re: [Pharo-project] [Metacello] Fwd: Metacello questions
by Dale Henrichs May 11, 2010

May 11, 2010

----- "Andreas.Raab" <andreas.raab(a)gmail.com> wrote: | 5) Bootstrapping Metacello? | | I found that most of the ConfigurationsOfXXX include some code to | 'bootstrap' Metacello in some form. There appear to be variants on | the | code; is there a "canonical bootstrap method" that should be used? | There is a canonical bootstrap method that is documented here: http://code.google.com/p/metacello/wiki/EnsureMetacello But the best technique is to copy the class MetacelloConfigTemplate where all of the required methods are already implemented... For more information see my answer to Question #6 below. | 6) A standard Configuration template? | | The Metacello tutorial is very useful as far as the configuration | goes | but it falls short of getting into the details of what it means to | provide a 'working' configuration. Testing the configuration isn't | covered (is there a way to get back to a 'clean' state?); | bootstrapping | isn't covered; the meaning of #isMetacelloConfig, | #metacelloVesion:loads:, #lastMetacelloVersionLoad and several other | -seemingly random- methods that can be found on most -but not all- of | the configurations. There is no indication on what these do, if | they're | required, recommended, or optional. Is there some 'standard' | Configuration template that people can use to avoid guessing about | which | parts of the boilerplate to copy from some other configuration? There is a FAQ on creating a new Metacello configuration: http://code.google.com/p/metacello/wiki/FAQ#How_do_I_create_a_Metacello_Con… but unfortunately the instructions are buried within a series of workspaces in ProfStef ... a Pharo-only package:( I've just extracted the instructions and added the following link to the FAQ answer: http://code.google.com/p/metacello/wiki/CreateMetacelloConfiguration Hope this helps, Dale

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Re: [Pharo-project] [Metacello] Fwd: Metacello questions
by Dale Henrichs May 11, 2010

May 11, 2010

Andreas, Your 'self answers' all look good. | spec | package:'Foo' with:[spec requires: 'Bar']; | package:'Foo' with:[spec requires: 'Baz']; | | and | spec | package: 'Foo' with:[spec requires: #('Bar' 'Baz')]. are indeed equivalent. So the difference pieces of the spec can be included in different #for:do: blocks based on the platform. To take you a little bit into the internals...You will notice that all packages/projects/groups are named, so for each spec of a given name an ordered list of modifications are recorded while resolving the spec on a given platform. 1. all #version: pragmas (no import and therefore self-contained) are processed first 2. #version:import: pragmas are processed next (using the imported version as a starting point). 3. within a #version: or #version:import: method, the specs are processed in project attribute order (i.e., for Squeak -> #common, #squeakCommon, #squeak). 4. the individual statements in the #for:do: for a given attribute are processed in order. 5. there are 4 unique operations supported: - add - copy - merge - remove Once the initial processing is complete, the operations are collapsed to form the final named spec. The named specs are collected into the version .... The #add operation is used by the constructors with 'overrides' in their name. The #add operation replaces the named spec. The #copy operation is used the by the #project:copyFrom:with: constructor. Note that #copy requires that an #add/#merge operation proceeds it in it's list. The #merge operation merges it's items into the previous version of the named spec. Not that #merge is equivalent to #add if the name spec doesn't exist yet. Most of the constructors use the #merge operation. The #remove operation is used by the constructors with 'remove' in their name. The #remove operation removes it's from the previous version of the named spec. So you can imagine that as you traverse through an attribute list for a particular project, that each of the individual constructor statements for a named spec are processed in a very specific order with each of the #add, #copy, #merge, and #remove operations applied in order... Hope this helps, Dale ----- "Andreas Raab" <andreas.raab(a)gmx.de> wrote: | On 5/6/2010 5:26 PM, Dale Henrichs wrote: | > I don't think I've completely answered your questions so we might | want to continue the dialog on this question.... | | We're getting close :-) Let me take my own questions and answer them | in | my own words to see if I understand the issues correctly: | | Q1: #includes: vs. #requires: | | If I understand correctly what you're saying then, in heavily | simplified | form, I'd say they're both dependencies, except that #requires: is | loaded before the package it relates to and #includes: afterwords. | Thus: | | spec package: 'B' with:[ | spec requires: 'A'. | spec includes: 'C'. | ]. | | will load A, B, and C in that order. One thing one can do with this is | | to have mutually dependent packages, for example if package Foo and | Bar | always must be loaded together (Foo before Bar) one would specify: | | spec package: 'Foo' with:[spec includes: 'Bar']. | spec package: 'Bar' with:[spec requires: 'Foo']. | | There is now no way by which Foo or Bar could be loaded without its | companion. Correct? | | Q2: Why is HelpSystem not loaded? | | A: That's a bug which I can work around by specifying either #version: | | or #versionString:. | | Q3: When exactly is HelpSystem loaded? | A: In the context of my configuration HelpSystem is loaded for two | reasons: a) because it's a dependency for WebClient-Help and b) | because | no 'default' group has been specified it would be loaded implicitly. | | Q4: How does one define dependencies that differ based on platform? | A: I'm not really sure about this. My understanding is that I could | use | #includes: to model the dependency in the "for: #pharo" branch, but | one | question that is still open is whether the following two expressions | are | equivalent: | | spec | package:'Foo' with:[spec requires: 'Bar']; | package:'Foo' with:[spec requires: 'Baz']; | | and | spec | package: 'Foo' with:[spec requires: #('Bar' 'Baz')]. | | Are these equivalent? | | Cheers, | - Andreas

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[Pharo-project] Incremental garbage collection
by Alexandre Bergel May 11, 2010

May 11, 2010

Hi! The garbage collection offered by the Pharo VM has two divisions. One for young objects, and another for old objects. I was wondering when a young object become old? I start to have a pretty good idea for human beings, but I am not so sure for Pharo objects. Is it when the object survives its first garbage collection? Cheers, Alexandre -- _,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;: Alexandre Bergel http://www.bergel.eu ^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;.

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[Pharo-project] Overlapped calls via NativeBoost [Was: Re: Single threaded Pharo IDE?]
by Igor Stasenko May 11, 2010

May 11, 2010

On 11 May 2010 21:24, Schwab,Wilhelm K <bschwab(a)anest.ufl.edu> wrote: > Sig, > > If you give us "overlapped calls," we'll make a statue of you. Â I'll bring the chissels :) > So, start preparing them. :) I need a feature request for it. How to make it convenient and what protocol/api you thinking of to make such calls. I can describe the things, which we need under the hood for implementation: - first, we need to create a common 'Native thread' class, which uses a native routine which it will run in it. So, you can create a donzens of native threads, each having own native function, and may serve for various purposes, not just for overlapped calls - second , we need to add a bindings for native semaphores and mutexes (so, we could generate a native code which can wait on them). - for overlapped calls, we need a special thread routine which runs a loop of following: - waits for 'action' native semapore - loads the arguments on stack and calls native function - stores the result on some 'results buffer' - signals 'result ready' interpreter's semaphore now, at language side , to do an overlapped call, we need - push arguments on some 'overlapped call' buffer - store the function pointer to call etc. - signal the 'action' native semaphore, so our overlapped call worker thread may proceed with call - wait for 'result ready' semaphore - fetch the result - return result. I would say, that its not hard to implement, but first, we requires some infrastructure before we can do it, namely: implement a NativeThread, and NativeSemaphore > On sockets, I'm not terribly worried about the blocking part: what I don't want is for the whole image to go under because of mis-typed URL or something. Â In short, I'm worried about too much blocking, not the absense of it. > > Bill > > > > -----Original Message----- > From: pharo-project-bounces(a)lists.gforge.inria.fr [mailto:pharo-project-bounces@lists.gforge.inria.fr] On Behalf Of Igor Stasenko > Sent: Monday, May 10, 2010 6:21 PM > To: Pharo-project(a)lists.gforge.inria.fr > Subject: Re: [Pharo-project] Single threaded Pharo IDE? > > 2010/5/11 Schwab,Wilhelm K <bschwab(a)anest.ufl.edu>: >> Andrei >> Having do-its block the UI is a feature, especially since you can >> explicitly fork a new (Smalltalk) process to do the work.Â What is >> **NOT** acceptable (and I fear I will discover is "easy" to cause to >> happen) is for DNS and socket operations that have been forked to block the main thread. >> > someone still has to do that for you, i.e. wait for a completion of blocking operation. > >> Dolphin has a feature called overlapped calls that allow external >> functions to be executed on a new OS thread specifically to avoid >> hanging the entire image.Â There are restrictions and disclaimers even >> then, and the default behavior is to block the UI. >> > Btw, its good that you mentioned this feature. > Given that i have a full control, what happens with NativeBoost, i could create a native thread to serve for handling such 'overlapped' calls, and at image side, it will just put a process, which made a call into a waitable state, while other processes could still continue to run. > > >> Bill >> >> ________________________________ >> From: pharo-project-bounces(a)lists.gforge.inria.fr >> [mailto:pharo-project-bounces@lists.gforge.inria.fr] On Behalf Of >> Andrei Stebakov >> Sent: Monday, May 10, 2010 5:31 PM >> To: Pharo-project(a)lists.gforge.inria.fr >> Cc: Adrian Lienhard >> Subject: Re: [Pharo-project] Single threaded Pharo IDE? >> >> >> >> 2010/5/10 Mariano Martinez Peck <marianopeck(a)gmail.com> >>> >>> >>> 2010/5/10 Andrei Stebakov <lispercat(a)gmail.com> >>>> >>>> >>>> I just started to use Pharo 1.0. So please bear with me since I may >>>> not fully understand the full concept of the IDE. Sometimes the >>>> whole IDE freezes indefinitely. >>> >>> Welcome ! we hope you enjoy ;) >>> >>>> >>>> So questions: >>>> 1) Looks like evaluating anything from the Workspace freezes the >>>> whole UI for the time of execution. Is it a bug or a feature? >>> >>> More or less. Pharo has a green thread implementation. I will tell >>> you what I understand. Green threads means, there is only ONE OS >>> thread, and then, internally (in Smalltalk) there exists their own >>> threads, scheduler, priorities, etc. The UI is just a process that is >>> running, with a certain priority. Go to the world menu, then "Tools" >>> -> "Process Browser". There you will see all the current processes >>> with their priorities. You can notice the UI process. >>> >> But you must agree that it still looks fishy when your whole UI blocks >> when you execute something lengthy (like new package install)... >> Well, if the majority of Pharo users think that it's OK who am I to argue? >> ;) >> >> >>> Â So...whatever you do here, it will be done inside that process. If >>> you do normal things, then yes, I guess the UI freezes. However, you >>> way want to launch another thread to do what you want and with a >>> lower priority than the UI. >>> >>> Do this test: open a workspace and a transcript. In the workspace, >>> evaluate: >>> >>> [ 1000 timesRepeat: [Transcript show: 'mariano'; cr] ] forkAt: >>> Processor userBackgroundPriority >>> >>> there, you will see that you are able to use the ide, while the block >>> of writing to Transcript is working "at the same time". >>> >>> Here the most important message is forkAt:Â Â Â . fork just fork the >>> block with the standard priority ("Processor activePriority"). If you >>> want to specify the priority, you have to use forkAt: >> >> Yes, the [ HTTPSocket httpGet: 'http://www.pharo-project.org/home'] forkAt: >> Processor userBackgroundPriority doesn't block the UI anymore... >> If it's the way to go, shouldn't we have a "special non-blocking" >> Workspace which does exactly this (or have an option to run your >> Workspace command with a background priority)? >> >>> >>> >>>> >>>> 2) Sometimes executing something freezes the UI indefinitely. Is >>>> there a way to cancel the operation (other than restarting the image)? >>>> Strangely in my case the IDE froze on evaluating HTTPSocket httpGet: >>>> 'http://www.pharo-project.org/home' >>>> >>> >>> Yes, Sockets are an example where sometimes they block the whole image. >>> Are you behind a proxy ? do you have a timeout error after a while ? >>> I have just tested and it also freezes for me in Mac OS. I have no idea. >>> Maybe other can help. >> >> If I execute HTTPSocket httpGet: 'http://www.pharo-project.org/home'. >> in a Workspace having a Transcript window open, I got a never-ending >> messages in the Transcript window like: >> "redirecting to http://www.cmsbox.com/errors/hostnotfound.html". >> Yes, I am behind a firewall, but other urls work with the same command. >> >> >>> >>> But yes, usually (sometimes it doesn't work) there is a combination >>> of keys that send a system interruption. Check this links: >>> >>> http://wiki.squeak.org/squeak/899 >>> http://wiki.squeak.org/squeak/1542 >>> >> Great! Alt-. works. >>> >>> BTW Adrian, I think this deserves a FAQ entry as it has been asked >>> several times. >>> >>> Cheers >>> >>> Mariano >>> >>>> >>>> Thank you, >>>> Andrei >>>> >>>> _______________________________________________ >>>> Pharo-project mailing list >>>> Pharo-project(a)lists.gforge.inria.fr >>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >>> >>> >>> _______________________________________________ >>> Pharo-project mailing list >>> Pharo-project(a)lists.gforge.inria.fr >>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >> >> >> _______________________________________________ >> Pharo-project mailing list >> Pharo-project(a)lists.gforge.inria.fr >> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >> > > > > -- > Best regards, > Igor Stasenko AKA sig. > > _______________________________________________ > Pharo-project mailing list > Pharo-project(a)lists.gforge.inria.fr > http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project > _______________________________________________ > Pharo-project mailing list > Pharo-project(a)lists.gforge.inria.fr > http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project > -- Best regards, Igor Stasenko AKA sig.

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Re: [Pharo-project] could we start to organize MetacelloRepository?
by Dale Henrichs May 11, 2010

May 11, 2010

Stef, Just thinking off the top of my head a bit. Conceptually a separate repository makes sense ... then Gofer Project could be setup to to use this repository by default and the standard instructions for loading things would be reduced to simple expressions like: Gofer project load: 'FFI'. Gofer project load: 'Magma'. The difficulty comes in keeping the repository up-to-date....First you'd need to qualify configurations for inclusion (a hudson server for validation) makes sense. For hudson, it would be nice if there were a list of candidate configuration/version pairs that would be tested against ... In reality we are really looking for an approved list of configuration/version pairs that are known to work in Pharo 1.0. So we're probably really interested in expressions like the following: Gofer project load: 'FFI' version: '1.2'. Gofer project load: 'Magma' version: '1.0r44'. At this point a separate repository becomes a little less useful ... it's not the Configuration alone that the end user is interested in as the version is very important and the important information is that it is "known to work" This leads me to think along the lines of - configs from MetacelloRepository - hudson server validating each version for each config - list of config/(latest passing version) pairs published It would seem to me that a relatively simple morphic/glamour window could be written that read the config/version pairs from the hudson server and provided a means for selecting/loading the config/version pairs. How does this sound? Dale ----- "StÃ©phane Ducasse" <stephane.ducasse(a)inria.fr> wrote: | Hi Dale and others | | I would like to have a | Pharo1.0 folder in the MetacelloRepository and ideally all the | configurationOf... inside should work for Pharo 1.0. | How can we proceed to get that. | In the future we should also have a process to avoid that we get junk | inside. any idea (I was thinking about an hudson | server that would validate the configuration automatically) | | Stef

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[Pharo-project] Single threaded Pharo IDE?
by Andrei Stebakov May 11, 2010

May 11, 2010

I just started to use Pharo 1.0. So please bear with me since I may not fully understand the full concept of the IDE. Sometimes the whole IDE freezes indefinitely. So questions: 1) Looks like evaluating anything from the Workspace freezes the whole UI for the time of execution. Is it a bug or a feature? 2) Sometimes executing something freezes the UI indefinitely. Is there a way to cancel the operation (other than restarting the image)? Strangely in my case the IDE froze on evaluating HTTPSocket httpGet: ' http://www.pharo-project.org/home' Thank you, Andrei

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May 11, 2010

11351 ----- - HashedCollection: postCopy back for Set before removing it from hashedCollection

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[Pharo-project] Migrating among different Pharo releases
by Mariano Martinez Peck May 11, 2010

May 11, 2010

Hi folks. I think we need to improve the changes/changelog between Pharo versions: 1.0, 1.1 etc. In addition, we need to document somewhere, how external packages maitainers should update their code. Sometimes, with a deprecated it is easy as you can say which other message to use instead. However, removing TheWorldMenu, FillInTheBlank, Preferences, etc it is more complicated as you cannot deprecated. So...if we want maintainers of external packages to update their versions to work with Pharo 1.1 we should document and explain what to do for these situations. For example, I have NO IDEA what to do with code that has references to those classes. Seriously, I don't have idea how to fix them. I propose something like Seaside at least: http://www.seaside.st/documentation/migration/28to30 Maybe the best start point is: http://code.google.com/p/pharo/wiki/ActionsInPharoOneDotOne Sorry I cannot help by myself with this. I am just speaking in case someone can know and can spent few hours and help with this. Cheers Mariano

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[Pharo-project] Fwd: Re: DEVImageCreator >> setDefaultPreferences (alain?)
by Alain Plantec May 11, 2010

May 11, 2010

-------- Message original -------- Sujet: Re: DEVImageCreator >> setDefaultPreferences (alain?) Date : Tue, 11 May 2010 13:55:41 +0200 De : Alain Plantec <alain.plantec(a)free.fr> RÃ©pondre Ã : alain.plantec(a)free.fr Pour : Mariano Martinez Peck <marianopeck(a)gmail.com> Hi Mariano, all Le 11/05/2010 11:43, Mariano Martinez Peck a Ã©crit : > Hi Alain. DEVImageCreator has to be updated to use the new > preferences. I can do it but it will require much more than for me > than for you ;) > > For preferences it is DEVImageCreator>> setDefaultPreferences > it is using Preferences class for the moment. It should be updated to > use Settings, isn't it ? I don't think so. There is no need for such a initialization anymore since package are defining their own preferences. If a default value is desired then it should be set by an initialization method or lazily by the getter. I find the lazy initialization better because then, the SettingBrowser can reset the preference to the default by setting it to nil. > BTW, Preferences is still present in Pharo 1.1 and thus, > setDefaultPreferences is still working but I guess it should be updated. why ? there is no need for setDefaultPreferences anymore. > > Do you know when Preferences class will be completely removed? Pharo 1.2? I don't know. Maybe we can let it in the 1.1 in order to let maintainers the possibility to port their packages and definitively remove it in 1.2. The same for TheWorldMenu I guess. Cheers Alain > > Thanks! > > Mariano

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