February 2022 - Pharo-users

Re: [Pharo-users] Re: What is "Fluid"?

by contactme＠kathe.in

On Monday, February 07, 2022 08:57 CET, Marcus Denker <marcus.denker(a)inria.fr> wrote: Â > On 7 Feb 2022, at 08:41, contactme(a)kathe.in wrote: > > Hello Marcus, > > Thanks for responding with thorough details, but I'm not such a good OO programmer, so what I need to know is; > Will we be able to continue developing with Pharo using the same old Smalltalk-like syntax? Or, will there be major changes some time in the future? Like how (I think) "_" from Squeak was replaced with ":=" in Pharo! > := is I think even ANSI Standard, or not? There are no plans for syntactical changesâ¦ But of course: The *goal* of Pharo is not to be Smalltalk80. I have to admit I kind of misunderstood Squeak back thenâ¦ I really thought the idea if was to take ST80 as a startingoint âto invent the futureââ¦ I still like that idea, I have to sayâ¦ to me what fascinates me is how to take something that is as of a great idea as ST80 and improve itâ¦ for example just consider the resources (in terms of memory or processing power or networking) we have today vs. 1978. The âletâs through it all away and start from scratchâ approach is not great, eitherâ¦ as you need something to buld upon. And: as soon as you finish that âbetterâ system, you would have the same problem: you would be stuck with a âfinishedâ system, while the world continues to evolve. It is a real interesting research question: How an you build Systems that can evolve over a long time ? Systems which evolve over time need to have a very tiny core which is supremely malleable. For one, I would start with a "Forth" and add an object-system to it using the "Metaobject Protocol" along with a Common Lisp like "Condition System". Â

Feb. 7, 2022

Re: What is "Fluid"?

by Marcus Denker

> On 7 Feb 2022, at 08:41, contactme(a)kathe.in wrote: > > Hello Marcus, > > Thanks for responding with thorough details, but I'm not such a good OO programmer, so what I need to know is; > Will we be able to continue developing with Pharo using the same old Smalltalk-like syntax? Or, will there be major changes some time in the future? Like how (I think) "_" from Squeak was replaced with ":=" in Pharo! > := is I think even ANSI Standard, or not? There are no plans for syntactical changesâ¦ But of course: The *goal* of Pharo is not to be Smalltalk80. I have to admit I kind of misunderstood Squeak back thenâ¦ I really thought the idea if was to take ST80 as a startingoint âto invent the futureââ¦ I still like that idea, I have to sayâ¦ to me what fascinates me is how to take something that is as of a great idea as ST80 and improve itâ¦ for example just consider the resources (in terms of memory or processing power or networking) we have today vs. 1978. The âletâs through it all away and start from scratchâ approach is not great, eitherâ¦ as you need something to buld upon. And: as soon as you finish that âbetterâ system, you would have the same problem: you would be stuck with a âfinishedâ system, while the world continues to evolve. It is a real interesting research question: How an you build Systems that can evolve over a long time ? Marcus

Feb. 7, 2022

Re: [Pharo-users] Re: What is "Fluid"?

by contactme＠kathe.in

Hello Marcus, Thanks for responding with thorough details, but I'm not such a good OO programmer, so what I need to know is; Will we be able to continue developing with Pharo using the same old Smalltalk-like syntax? Or, will there be major changes some time in the future? Like how (I think) "_" from Squeak was replaced with ":=" in Pharo! Thank you. On Wednesday, February 02, 2022 10:50 CET, Marcus Denker <marcus.denker(a)inria.fr> wrote: Â > On 2 Feb 2022, at 09:04, contactme(a)kathe.in wrote: > > I have attached 2 cropped screen-captures of the same class displayed in the class browser; > class-smalltalk.png is the regular class syntax, > class-fluid.png is the same class but with the "Fluid" checkbox selected, and shows a different syntax. > This is no different syntax, as there is no Syntax (in the sense of Grammar) to define classes. These are all message sends, just like before. > May I know what that is all about? > > There's a different terminology too, something called "slot", which I have faint memories of being quite like that in "Self" environments. > The Fluid class definition has two goals: 1) be extensible. With the ST80 way, any new parameter would mean adding *a lot* of methods. And every new parameter needs all the other variations, itâs a serious combinatorial explosion. Just an example: CompiledMethods and CompiledBlock use CompiledMethodLayout. But they are created with: CompiledCode variableByteSubclass: #CompiledMethod instanceVariableNames: '' classVariableNames: '' package: 'Kernel-Methods' So the system checks for the name and uses the CompiledMethodLayout instead of ByteLayout. This is hacked in to the system really with âif the name is CompiledMethod, do not use ByteLayout but CompiledMethodLayout.â But now CompiledCode classLayout ==> "a CompiledMethodLayoutâ Which means yes, we have a class that we can not define! With the new class definition, this is explicit: CompiledCode << #CompiledBlock layout: CompiledMethodLayout; slots: {}; tag: 'Methods'; package: âKernel' Now of course we could have added ~20 methods (not sure if that is enoughâ¦) of a compiledMethodSubclass:, and added a version with the layout as a parameter (another 20+1 variants). But what if we want to add yet another parameter? What is *you* want to do that? With Fluid, class defintions are extensible, and we can easily extend them. 2) Why are variables not a list of names in a String anymore? Because we have âFirst Class Variablesâ: every variable in the system has a meta-object, which is implemented by a class. Point instanceVariables first "#x => InstanceVariableSlotâ So yes, there is an Object that represents âthe variable #x in Pointâ. With an api. The compiler delegates code generation to it fore read and write. You can think of it as a Meta Object Protocol for Variables... (I sometimes wonder if the name Slot was good, we could just think of it as âInstanceVariableâ in the sense of the Variable being modelled as an object, instead of a String). This is a big topic, but the idea is: letâs use Objects, not Strings! We can define our own kind of Variable (see the hierarchy of Variable), and the use of the array {} now allows us to actually define a class that uses this special kind of Variable. There is a presentation I did about it last year: https://vimeo.com/603398445 Marcus Â Â

Feb. 7, 2022

Re: aio event forwarding not supported

by Davide Varvello

Hi Stephane > On Saturday, February 5, 2022, 10:58:37 AM GMT+1, stephane.ducasse(a)free.fr <stephane.ducasse(a)free.fr> wrote: >Hi david > >Can you tell us on which version of os-x you are? I'm on Big Sur, see my original message:Â https://www.mail-archive.com/pharo-users@lists.pharo.org/msg40530.html And the bug I openedÂ https://pharo.fogbugz.com/f/cases/22925/aio-event-forwarding-not-supportedÂ > We faced many glitches with monterrey. For example sometimes at startup my images do not get events :( > Pablo is going on vacation for two weeks and esteban and me too :) > So we will be slower to react.Â > Now you face what we face, the world keeps changing under our feets and > this brings us many things that we did not want/plan to work on. > This is why VMs are nice for the users they abstract the shit underneath but nevertheless it exists. > S I know it's a tough job, I'm trying to implement a workaround, thanks for your work. Davide

Feb. 5, 2022

Re: aio event forwarding not supported

by David T. Lewis

Hi David, I do not think I can help, maybe someone with Big Sur can take a look? I am on Linux. I did a fresh download of Pharo 8 and loaded OSProcess, and I cannot reproduce the problem on my system. Dave On Fri, Feb 04, 2022 at 03:54:57PM +0000, Davide Varvello via Pharo-users wrote: > Hi David,I don't think is an issue of warning, even if I apply your patch I have the same error, see: https://imgur.com/a/pYcLLWx > > > > To reproduce the bug:??Be on ??Big Sur 11.6.3 (20G415) https://support.apple.com/en-us/HT213055Download Pharo 8: curl https://get.pharo.org/64/80+vm|bash > Open the image and evaluate ina playground:Metacello new???? ?? configuration: 'OSProcess';???? ?? repository: 'http://www.squeaksource.com/MetacelloRepository';?? ?? load . > > and then > (PipeableOSProcess command: 'ps') ??output. > > The bug will show itself > CheersDavide > On Friday, February 4, 2022, 04:39:28 PM GMT+1, David T. Lewis <lewis(a)mail.msen.com> wrote: > > Hi Davide, > > Actually the warning has been removed in newer versions of OSProcess. > I do not have time to do an update for Pharo now, but in the mean time > you can apply this change in your image to remove the notifier: > > AioEventHandler>>initializeForExceptions: exceptionEventFlag readEvents: readEventFlag writeEvents: writeEventFlag > ?????? semaphore := Semaphore new. > ?????? semaIndex := Smalltalk registerExternalObject: semaphore. > ?????? (AioPluginPresent = true) ifTrue: [ > ?????? ?????? ([self aioEnable: self descriptor forSemaphore: self semaIndex externalObject: true] > ?????? ?????? ?????? on: Warning > ?????? ?????? ?????? do: [:e | > ?????? ?????? ?????? ?????? self close. "unregister the semaphore" > ?????? ?????? ?????? ?????? OSProcess trace: e messageText asString. nil]) > ?????? ?????? ?????? ifNotNil: > ?????? ?????? ?????? ?????? [handlerProc := self > ?????? ?????? ?????? ?????? ?????? handleExceptions: exceptionEventFlag > ?????? ?????? ?????? ?????? ?????? readEvents: readEventFlag > ?????? ?????? ?????? ?????? ?????? writeEvents: writeEventFlag]] > > > HTH, > Dave > > > > On Fri, Feb 04, 2022 at 03:05:57PM +0000, Davide Varvello wrote: > >?? Hi David,That's weird because if the AioPlugin is not present in my VM,??PipeableOSProcess shouldn't have worked till this morning... when I upgraded my mac :-) > > The warning is not skippable, it stops me at:??MessageNotUnderstood: IRJump>> #nextBytecodeOffsetAfterJumpCheersDavide > > > >?? ?? On Friday, February 4, 2022, 03:54:59 PM GMT+1, David T. Lewis <lewis(a)mail.msen.com> wrote:?? > >?? > >?? On Fri, Feb 04, 2022 at 01:46:46PM +0000, Davide Varvello via Pharo-users wrote: > > > Hi guys, > > > Suddenly evaluating a simple: (PipeableOSProcess command: 'ps') output, or any other PipeableOSProcess command, Pharo gives me: "aio event forwarding not supported". > > > I guess it is something related to the latest update of the OS, specifically Big Sur 11.6.3 (20G415) https://support.apple.com/en-us/HT213055I'm on a Mac, of course, Pharo 8.0.0, Build information: Pharo-8.0.0+build.1128.sha.9f6475d88dda7d83acdeeda794df35d304cf620d (64 Bit) > > > Can you help me, please?CheersDavide > > > > Hi Davide, > > > > The warning message indicates that the AioPlugin is not present > > in your VM. I do not know the reason for that, although your > > PipeableOSProcess should still work if you proceed through the > > warning. > > > > Dave > > > >?? >

Feb. 4, 2022

Error when running OSUnixSubprocess - posix_spawn() error

by bajger＠gmail.com

Greetings Pharoers! I have following problem when using OSSubprocess library. If I run a method that uses code below, it fails: Error: Error: posix_spawn(), code: 9, description: Bad file descriptor Any thoughts, hints are welcome! My code redirects stdout, stdin in order to catch system outputs from inside of Pharo. ``` Subprocess code does following: OSUnixSubprocess>>runAndWaitWithStdOutput ``` ``` self ``` ``` redirectStdout; ``` ``` redirectStderr; ``` ``` runAndWaitOnExitDo: [ :termProcess :outString :errString | ``` ``` termProcess isSuccess ``` ``` ifTrue: [ ^ outString ] ``` ``` ifFalse: [ "commands to handle ex message here" ] ] ``` ``` Now if I run, it fails: Error: Error: posix_spawn(), code: 9, description: Bad file descriptor OSSUnixSystemAccessor(Object)>>error: OSSUnixSystemAccessor>>strerror:message: OSSUnixSubprocess>>internalRun [ self internalRun ] in OSSUnixSubprocess>>run in Block: [ self internalRun ] BlockClosure>>ensure: OSSUnixSubprocess>>run OSSUnixSubprocess>>runAndWaitOnExitDo: OSSUnixSubprocess>>runAndWaitWithStdOutput ... .. . PhLImageProcessListCliCommand(PhLCliCommand)>>executeOSShellCommand So it seems that OSUnixSubprocess uses some file that remains opened probably in OS? Command that is passed to OSSubprocess is generated by args: ^ Array with: 'echo' with: '-n' with: ('$(pgrep -a -f Pharo | grep ''.image'' | grep -v ''.bash''| grep -v {1})' format: {self currentVMPid asString}) ```

Feb. 4, 2022

Re: aio event forwarding not supported

by Davide Varvello

Hi David,I don't think is an issue of warning, even if I apply your patch I have the same error, see: https://imgur.com/a/pYcLLWx To reproduce the bug:Â Be on Â Big Sur 11.6.3 (20G415) https://support.apple.com/en-us/HT213055Download Pharo 8: curl https://get.pharo.org/64/80+vm|bash Open the image and evaluate ina playground:Metacello newÂ Â Â configuration: 'OSProcess';Â Â Â repository: 'http://www.squeaksource.com/MetacelloRepository';Â Â load . and then (PipeableOSProcess command: 'ps') Â output. The bug will show itself CheersDavide On Friday, February 4, 2022, 04:39:28 PM GMT+1, David T. Lewis <lewis(a)mail.msen.com> wrote: Hi Davide, Actually the warning has been removed in newer versions of OSProcess. I do not have time to do an update for Pharo now, but in the mean time you can apply this change in your image to remove the notifier: AioEventHandler>>initializeForExceptions: exceptionEventFlag readEvents: readEventFlag writeEvents: writeEventFlag Â Â Â semaphore := Semaphore new. Â Â Â semaIndex := Smalltalk registerExternalObject: semaphore. Â Â Â (AioPluginPresent = true) ifTrue: [ Â Â Â Â Â Â ([self aioEnable: self descriptor forSemaphore: self semaIndex externalObject: true] Â Â Â Â Â Â Â Â Â on: Warning Â Â Â Â Â Â Â Â Â do: [:e | Â Â Â Â Â Â Â Â Â Â Â Â self close. "unregister the semaphore" Â Â Â Â Â Â Â Â Â Â Â Â OSProcess trace: e messageText asString. nil]) Â Â Â Â Â Â Â Â Â ifNotNil: Â Â Â Â Â Â Â Â Â Â Â Â [handlerProc := self Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â handleExceptions: exceptionEventFlag Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â readEvents: readEventFlag Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â writeEvents: writeEventFlag]] HTH, Dave On Fri, Feb 04, 2022 at 03:05:57PM +0000, Davide Varvello wrote: >Â Hi David,That's weird because if the AioPlugin is not present in my VM,??PipeableOSProcess shouldn't have worked till this morning... when I upgraded my mac :-) > The warning is not skippable, it stops me at:??MessageNotUnderstood: IRJump>> #nextBytecodeOffsetAfterJumpCheersDavide > >Â Â On Friday, February 4, 2022, 03:54:59 PM GMT+1, David T. Lewis <lewis(a)mail.msen.com> wrote:Â >Â >Â On Fri, Feb 04, 2022 at 01:46:46PM +0000, Davide Varvello via Pharo-users wrote: > > Hi guys, > > Suddenly evaluating a simple: (PipeableOSProcess command: 'ps') output, or any other PipeableOSProcess command, Pharo gives me: "aio event forwarding not supported". > > I guess it is something related to the latest update of the OS, specifically Big Sur 11.6.3 (20G415) https://support.apple.com/en-us/HT213055I'm on a Mac, of course, Pharo 8.0.0, Build information: Pharo-8.0.0+build.1128.sha.9f6475d88dda7d83acdeeda794df35d304cf620d (64 Bit) > > Can you help me, please?CheersDavide > > Hi Davide, > > The warning message indicates that the AioPlugin is not present > in your VM. I do not know the reason for that, although your > PipeableOSProcess should still work if you proceed through the > warning. > > Dave > >Â

Feb. 4, 2022

Re: aio event forwarding not supported

by David T. Lewis

Hi Davide, Actually the warning has been removed in newer versions of OSProcess. I do not have time to do an update for Pharo now, but in the mean time you can apply this change in your image to remove the notifier: AioEventHandler>>initializeForExceptions: exceptionEventFlag readEvents: readEventFlag writeEvents: writeEventFlag semaphore := Semaphore new. semaIndex := Smalltalk registerExternalObject: semaphore. (AioPluginPresent = true) ifTrue: [ ([self aioEnable: self descriptor forSemaphore: self semaIndex externalObject: true] on: Warning do: [:e | self close. "unregister the semaphore" OSProcess trace: e messageText asString. nil]) ifNotNil: [handlerProc := self handleExceptions: exceptionEventFlag readEvents: readEventFlag writeEvents: writeEventFlag]] HTH, Dave On Fri, Feb 04, 2022 at 03:05:57PM +0000, Davide Varvello wrote: > Hi David,That's weird because if the AioPlugin is not present in my VM,??PipeableOSProcess shouldn't have worked till this morning... when I upgraded my mac :-) > The warning is not skippable, it stops me at:??MessageNotUnderstood: IRJump>> #nextBytecodeOffsetAfterJumpCheersDavide > > On Friday, February 4, 2022, 03:54:59 PM GMT+1, David T. Lewis <lewis(a)mail.msen.com> wrote: > > On Fri, Feb 04, 2022 at 01:46:46PM +0000, Davide Varvello via Pharo-users wrote: > > Hi guys, > > Suddenly evaluating a simple: (PipeableOSProcess command: 'ps') output, or any other PipeableOSProcess command, Pharo gives me: "aio event forwarding not supported". > > I guess it is something related to the latest update of the OS, specifically Big Sur 11.6.3 (20G415) https://support.apple.com/en-us/HT213055I'm on a Mac, of course, Pharo 8.0.0, Build information: Pharo-8.0.0+build.1128.sha.9f6475d88dda7d83acdeeda794df35d304cf620d (64 Bit) > > Can you help me, please?CheersDavide > > Hi Davide, > > The warning message indicates that the AioPlugin is not present > in your VM. I do not know the reason for that, although your > PipeableOSProcess should still work if you proceed through the > warning. > > Dave > >

Feb. 4, 2022

Re: aio event forwarding not supported

by Davide Varvello

Hi David,That's weird because if the AioPlugin is not present in my VM,Â PipeableOSProcess shouldn't have worked till this morning... when I upgraded my mac :-) The warning is not skippable, it stops me at:Â MessageNotUnderstood: IRJump>> #nextBytecodeOffsetAfterJumpCheersDavide On Friday, February 4, 2022, 03:54:59 PM GMT+1, David T. Lewis <lewis(a)mail.msen.com> wrote: On Fri, Feb 04, 2022 at 01:46:46PM +0000, Davide Varvello via Pharo-users wrote: > Hi guys, > Suddenly evaluating a simple: (PipeableOSProcess command: 'ps') output, or any other PipeableOSProcess command, Pharo gives me: "aio event forwarding not supported". > I guess it is something related to the latest update of the OS, specifically Big Sur 11.6.3 (20G415) https://support.apple.com/en-us/HT213055I'm on a Mac, of course, Pharo 8.0.0, Build information: Pharo-8.0.0+build.1128.sha.9f6475d88dda7d83acdeeda794df35d304cf620d (64 Bit) > Can you help me, please?CheersDavide Hi Davide, The warning message indicates that the AioPlugin is not present in your VM. I do not know the reason for that, although your PipeableOSProcess should still work if you proceed through the warning. Dave

Feb. 4, 2022

Re: aio event forwarding not supported

by David T. Lewis

On Fri, Feb 04, 2022 at 01:46:46PM +0000, Davide Varvello via Pharo-users wrote: > Hi guys, > Suddenly evaluating a simple: (PipeableOSProcess command: 'ps') output, or any other PipeableOSProcess command, Pharo gives me: "aio event forwarding not supported". > I guess it is something related to the latest update of the OS, specifically Big Sur 11.6.3 (20G415) https://support.apple.com/en-us/HT213055I'm on a Mac, of course, Pharo 8.0.0, Build information: Pharo-8.0.0+build.1128.sha.9f6475d88dda7d83acdeeda794df35d304cf620d (64 Bit) > Can you help me, please?CheersDavide Hi Davide, The warning message indicates that the AioPlugin is not present in your VM. I do not know the reason for that, although your PipeableOSProcess should still work if you proceed through the warning. Dave

Feb. 4, 2022