July 2014 - Pharo-dev - lists.pharo.org

Re: [Pharo-dev] Doubt in Pharo

by stepharo

Hi Dokania I hope that you do not doubt that Pharo is a cool system :) > Hello, > > I am creating an Object Relational Mapper in pharo using sqlite. > > While creating database I am using a dictionary for columns of Database. This gives me Keys as column name and values as Data type of those. > > So suppose Employee is the the table name, with ID->Integer, Name->Text, Salary->Float. > > emp:= Employee new. > Now emp is a row of table, so for each row user has to create instance of Employee and then feed values to it. Later on he can pass message insert query to emp. > > So I was creating this dictionary for column at the instance side initialization of Employee. > > My instructor suggested to do that in class side initialization, > > My Doubts are: > > 1. Why should we do class side initialization instead of instance side initialization. Because class side initialization is executing once when the class is loaded in memory. And I imagine that you do not want to change and execute the mapping declaration for every single instance you will create. isn't? So Object subclass: #Employee instanceVariableNames: '' classVariableNames: 'Mappings' category: 'Foo-Model' Employee class>>initialize Mappings := { #ID->Integer . #Name->Text. #Salary->Float } asDictionary makes a lot of sense. or Object subclass: #Employee instanceVariableNames: '' classVariableNames: '' category: 'Foo-Model' Employee class instanceVariableNames: 'mappings' Employee class>>initialize mappings := { #ID->Integer . #Name->Text. #Salary->Float } asDictionary Read pharo by example to understand the difference between class variable (Shared Variable) and class instance variables > > 2. Could you please refer me to the link which explains how to do class side initialization. Because when I do Employee new, I see only instance side initialization is being called. Employee initialize you send a message to the CLASS itself to get **ITS** initialize method execute. Normally when you load the class its initialize method is automatically executed. When you do Employee new => Employee basicNew initialize => anEmployee initialize => anInitializedEmployee > > Thanks, > Harshit > > >

July 23, 2014

Re: [Pharo-dev] transformmorph and submorph bounds

by Tudor Girba

Hi, On Wed, Jul 23, 2014 at 9:52 AM, Thierry Goubier <thierry.goubier(a)gmail.com> wrote: > > > > 2014-07-23 8:00 GMT+02:00 Tudor Girba <tudor(a)tudorgirba.com>: > > Hi, >> >> In GTInspector we use a TransformMorph inside the pager morph. It works >> fine, but spawning completion from a text morph that is placed inside this >> transform morph, the completion morphs appears in the wrong place. >> >> The issue comes from submorphBounds apparently not being right (this is >> what the completion morph relies on). >> >> Here is a simpler example, to exemplify what I am talking about: >> >> circle := CircleMorph new. >> morph := TransformMorph new. >> morph addMorph: circle. >> morph top: 100. >> morph left: 100. >> morph submorphBounds. "==> (100@100) corner: (140@140)" >> circle submorphBounds. "==> (0@0) corner: (40@40)" >> > > This seems correct to me: a transformMorph is the one which shift its > contents (and reset the origin to its top left corner ?). > Not really. The contract of submorphBounds should be that it returns an absolute coordinate, as far as I understand. > Why do you use a TransformMorph there? > It is used for example in ScrollPane. This means that if you embed a TextMorph inside a ScrollPane, you will have the same problem with completion: scrollPane := ScrollPane new. pasteUpMorph := PasteUpMorph new. scrollPane scroller addMorph: pasteUpMorph. scrollPane openInWindow top: 100; left: 100. pasteUpMorph submorphBounds "(0@0) corner: (50@40)" Cheers, Doru > Thierry > > >> Ideally, "circle submorphBounds" should start at 100@100. Is this a bug, >> or am I doing something wrong? >> >> Cheers, >> Doru >> >> -- >> www.tudorgirba.com >> >> "Every thing has its own flow" >> > > -- www.tudorgirba.com "Every thing has its own flow"

July 23, 2014

[pharo-project/pharo-core] 0c052f: 40117

by GitHub

Branch: refs/heads/4.0 Home: https://github.com/pharo-project/pharo-core Commit: 0c052fbe84db7ec2db77bdac9ea4d8448638c2c4 https://github.com/pharo-project/pharo-core/commit/0c052fbe84db7ec2db77bdac… Author: Jenkins Build Server <board(a)pharo-project.org> Date: 2014-07-23 (Wed, 23 Jul 2014) Changed paths: R Kernel.package/CompiledMethod.class/instance/accessing/searchForClass.st R Kernel.package/CompiledMethod.class/instance/accessing/searchForSelector.st R KernelTests.package/CompiledMethodTest.class/instance/tests - accessing/testSearchForClass.st R KernelTests.package/CompiledMethodTest.class/instance/tests - accessing/testSearchForSelector.st M Refactoring-Critics.package/RBConsistencyCheckRule.class/instance/accessing/name.st M Refactoring-Critics.package/RBConsistencyCheckRule.class/instance/initialization/initialize.st A ScriptLoader40.package/ScriptLoader.class/instance/pharo - scripts/script117.st A ScriptLoader40.package/ScriptLoader.class/instance/pharo - updates/update40117.st M ScriptLoader40.package/ScriptLoader.class/instance/public/commentForCurrentUpdate.st Log Message: ----------- 40117 13656 remove CompiledMethod searchForClass and searchForSelector https://pharo.fogbugz.com/f/cases/13656 13657 Remove at: check from RBConsistencyCheckRule https://pharo.fogbugz.com/f/cases/13657 http://files.pharo.org/image/40/40117.zip

July 23, 2014

[pharo-project/pharo-core]

by GitHub

Branch: refs/tags/40117 Home: https://github.com/pharo-project/pharo-core

July 23, 2014

Re: [Pharo-dev] we need you on http://pharo.org/about

by Ben Coman

July 23, 2014

[pharo-project/pharo-core]

by GitHub

Branch: refs/tags/40116 Home: https://github.com/pharo-project/pharo-core

July 23, 2014

[pharo-project/pharo-core] 7c2532: 40116

by GitHub

Branch: refs/heads/4.0 Home: https://github.com/pharo-project/pharo-core Commit: 7c25328f3570b7ecd38a06d528845ab02f87edd8 https://github.com/pharo-project/pharo-core/commit/7c25328f3570b7ecd38a06d5… Author: Jenkins Build Server <board(a)pharo-project.org> Date: 2014-07-23 (Wed, 23 Jul 2014) Changed paths: A Graphics-Fonts.package/extension/BitBlt/instance/basicDisplayString_from_to_at_strikeFont_kern_.st A Graphics-Fonts.package/extension/BitBlt/instance/displayString_from_to_at_strikeFont_kern_.st R Graphics-Primitives.package/BitBlt.class/instance/copying/basicDisplayString_from_to_at_strikeFont_kern_.st R Graphics-Primitives.package/BitBlt.class/instance/copying/displayString_from_to_at_strikeFont_kern_.st A ScriptLoader40.package/ScriptLoader.class/instance/pharo - scripts/script116.st A ScriptLoader40.package/ScriptLoader.class/instance/pharo - updates/update40116.st M ScriptLoader40.package/ScriptLoader.class/instance/public/commentForCurrentUpdate.st R System-CommandLine.package/VTermInputDriver.class/README.md R System-CommandLine.package/VTermInputDriver.class/class/instance creation/on_.st R System-CommandLine.package/VTermInputDriver.class/class/instance creation/stdIn.st R System-CommandLine.package/VTermInputDriver.class/definition.st R System-CommandLine.package/VTermInputDriver.class/instance/accessing/handler_.st R System-CommandLine.package/VTermInputDriver.class/instance/accessing/inStream_.st R System-CommandLine.package/VTermInputDriver.class/instance/initialization/initialize.st R System-CommandLine.package/VTermInputDriver.class/instance/initialize-release/initializeCSI_.st R System-CommandLine.package/VTermInputDriver.class/instance/initialize-release/initializeNormal_.st R System-CommandLine.package/VTermInputDriver.class/instance/initialize-release/initializeSS3_.st R System-CommandLine.package/VTermInputDriver.class/instance/private/fail_in_.st R System-CommandLine.package/VTermInputDriver.class/instance/reading/continueReadCSINumber_.st R System-CommandLine.package/VTermInputDriver.class/instance/reading/read.st R System-CommandLine.package/VTermInputDriver.class/instance/reading/readC1.st R System-CommandLine.package/VTermInputDriver.class/instance/reading/readCSI.st R System-CommandLine.package/VTermInputDriver.class/instance/reading/readSS3.st R System-CommandLine.package/VTermInputDriver.class/instance/testing/closed.st A Tool-Transcript.package/extension/ThreadSafeTranscript/class/examples.st A Tool-Transcript.package/extension/ThreadSafeTranscript/class/examplesConcurrent.st A Tool-Transcript.package/extension/ThreadSafeTranscript/class/examplesForegroundUpdate.st A Tool-Transcript.package/extension/ThreadSafeTranscript/class/menuCommandOn_.st A Tool-Transcript.package/extension/ThreadSafeTranscript/instance/codePaneMenu_shifted_.st M Traits.package/TClass.class/instance/subclass creation - slots/subclass_layout_slots_classVariables_poolDictionaries_category_.st M Traits.package/TClass.class/instance/subclass creation - slots/subclass_slots_classVariables_poolDictionaries_category_.st M Traits.package/TClass.class/instance/subclass creation - slots/subclass_uses_layout_slots_classVariables_poolDictionaries_category_.st M Traits.package/TClass.class/instance/subclass creation - slots/subclass_uses_slots_classVariables_poolDictionaries_category_.st R Transcript.package/ThreadSafeTranscript.class/class/examples/examples.st R Transcript.package/ThreadSafeTranscript.class/class/examples/examplesConcurrent.st R Transcript.package/ThreadSafeTranscript.class/class/examples/examplesForegroundUpdate.st R Transcript.package/ThreadSafeTranscript.class/class/world menu/menuCommandOn_.st R Transcript.package/ThreadSafeTranscript.class/instance/menu/codePaneMenu_shifted_.st Log Message: ----------- 40116 13648 remove VTermInputDriver https://pharo.fogbugz.com/f/cases/13648 13651 move font related methods in BitBlt to Graphics-Fonts package https://pharo.fogbugz.com/f/cases/13651 13649 move ThreadSafeTranscript >> #codePaneMenu:shifted: to Tool-Transcript package https://pharo.fogbugz.com/f/cases/13649 13647 unimplemented #poolDictionaries called by Class, TClass and Trait https://pharo.fogbugz.com/f/cases/13647 13652 move class side ThreadSafeTranscript examples, menuCommandOn: and open to Tool-Transcript package https://pharo.fogbugz.com/f/cases/13652 http://files.pharo.org/image/40/40116.zip

July 23, 2014

Re: [Pharo-dev] Suspending a Process

by Nicolai Hess

Hi ben, thank you for looking at this. 2014-07-22 20:17 GMT+02:00 <btc(a)openinworld.com>: > I thought this might be interesting to learn, so I've gave it a go. I > had some success at the end, but I'll give a progressive report. > > First I thought I'd try moving the update of StringMorph outside the > worker-process using a Morph's #step method as follows... > > Morph subclass: #BackgroundWorkDisplayMorph > instanceVariableNames: 'interProcessString stringMorph' > classVariableNames: '' > category: 'BenPlay' > "---------" > > BackgroundWorkDisplayMorph>>initializeMorph > self color: Color red. > stringMorph := StringMorph new. > self addMorphBack: stringMorph. > self extent:(300@50). > "---------" > > BackgroundWorkDisplayMorph>>newWorkerProcess > ^[ > | work | > work := 0. > [ 20 milliSeconds asDelay wait. > work := work + 1. > interProcessString := work asString. > ] repeat. > ] newProcess. > "---------" > > BackgroundWorkDisplayMorph>>step > stringMorph contents: interProcessString. > "---------" > > BackgroundWorkDisplayMorph>>stepTime > ^50 > "---------" > > BackgroundWorkDisplayMorph>>initialize > | workerProcess running | > super initialize. > self initializeMorph. > > workerProcess := self newWorkerProcess. > running := false. > > self on: #mouseUp send: #value to: > [ (running := running not) > ifTrue: [ workerProcess resume. self color: Color green. ] > ifFalse: [ workerProcess suspend. self color: Color red. ] > ] > "---------" > > > > But evaluating "BackgroundWorkDisplayMorph new openInWorld" found this > exhibited the same problematic behavior you reported... Clicking on the > morph worked a few times and then froze the UI until Cmd-. pressed a few > times. > > However I found the following never locked the GUI. > > BackgroundWorkDisplayMorph>>initialize > "BackgroundWorkDisplayMorph new openInWorld" > | workerProcess running | > super initialize. > self initializeMorph. > > workerProcess := self newWorkerProcess. > running := false. > > [ [ (running := running not) > ifTrue: [ workerProcess resume. self color: Color green ] > ifFalse: [ workerProcess suspend. self color: Color red ]. > 10 milliSeconds asDelay wait. > ] repeat ] fork. > "---------" > > This locks the UI as well. Not every timet hough. I did this 5 times, every time in a freshly loaded image and it happens two times. > So the problem seemed to not be with #suspend/#resume or with the shared > variable /interProcessString/. Indeed, since in the worker thread > /interProcessString/ is atomically assigned a copy via #asString, and the > String never updated, I think there is no need to surround use of it with a > critical section. > > The solution then was to move the "#resume/#suspend" away from the "#on: > #mouseUp send: #value to:" as follows... > > BackgroundWorkDisplayMorph>>initialize > "BackgroundWorkDisplayMorph new openInWorld" > | workerProcess running lastRunning | > super initialize. > self initializeMorph. > > workerProcess := self newWorkerProcess. > lastRunning := running := false. > > [ [ lastRunning = running ifFalse: > [ running > ifTrue: [ workerProcess resume ] > ifFalse: [ workerProcess suspend ]. > lastRunning := running. > ]. > 10 milliSeconds asDelay wait. > ] repeat ] fork. > > self on: #mouseUp send: #value to: > [ (running := running not) > ifTrue: [ self color: Color green. ] > ifFalse: [ self color: Color red. ] > ] > "---------" > And this too :( > > And finally remove the busy loop. > > BackgroundWorkDisplayMorph>>initialize > "BackgroundWorkDisplayMorph new openInWorld" > | workerProcess running lastRunning semaphore | > super initialize. > self initializeMorph. > > workerProcess := self newWorkerProcess. > lastRunning := running := false. > semaphore := Semaphore new. > > [ [ semaphore wait. > running > ifTrue: [ workerProcess resume ] > ifFalse: [ workerProcess suspend ]. > ] repeat ] fork. > > self on: #mouseUp send: #value to: > [ (running := running not) > ifTrue: [ self color: Color green. ] > ifFalse: [ self color: Color red. ]. > semaphore signal. > ] > "---------" > > And this locks the UI too. (Loaded the code 20 times, every time after a fresh image start up. Two times I got a locked ui after the first two clicks). And I don't understand this code :) > Now I can't say how close that is to how it "should" be done. Its the > first time I used sempahores and just what I discovered hacking around. > But hey! it works :) > > cheers -ben > > > > Nicolai Hess wrote: > > I am still struggling with it. > > Any ideas? > > > 2014-07-09 11:19 GMT+02:00 Nicolai Hess <nicolaihess(a)web.de>: > >> >> >> >> 2014-07-09 2:07 GMT+02:00 Eliot Miranda <eliot.miranda(a)gmail.com>: >> >> Hi Nicolai, >>> >>> >>> On Tue, Jul 8, 2014 at 7:19 AM, Nicolai Hess <nicolaihess(a)web.de> >>> wrote: >>> >>>> I want to create a process doing some work and call #changed on a >>>> Morph. >>>> I want to start/suspend/resume or stop this process. >>>> But sometimes, suspending the process locks the UI-Process, >>>> and I don't know why. Did I miss something or do I have to care when to >>>> call suspend? >>>> >>>> Wrapping the "morph changed" call in >>>> UIManager default defer:[ morph changed]. >>>> Does not change anything. >>>> >>>> Here is an example to reproduce it. >>>> Create the process, >>>> call resume, call supsend. It works, most of the time, >>>> but sometimes, calling suspend locks the ui. >>>> >>>> p:=[[true] whileTrue:[ Transcript crShow: (DateAndTime now asString). >>>> 30 milliSeconds asDelay wait]] newProcess. >>>> >>> p resume. >>>> p suspend. >>>> >>> >>> If you simply suspend this process at random form a user-priority >>> process you'll never be able to damage the Delay machinery you're using, >>> but chances are you'll suspend the process inside the critical section that >>> Transcript uses to make itself thread-safe, and that'll lock up the >>> Transcript. >>> >> >> Thank you Eliot >> yes I guessed it locks up the critical section, but I hoped with would >> not happen if I the use UIManager defer call. >> >> >> >>> >>> ThreadSafeTranscript>>nextPutAll: value >>> accessSemaphore >>> critical: [stream nextPutAll: value]. >>> ^value >>> >>> So instead you need to use a semaphore. e.g. >>> >>> | p s wait | >>> s := Semaphore new. >>> p:=[[true] whileTrue:[wait ifTrue: [s wait]. Transcript crShow: >>> (DateAndTime now asString). 30 milliSeconds asDelay wait]] newProcess. >>> wait := true. >>> 30 milliSeconds asDelay wait. >>> wait := false. >>> s signal >>> >>> etc... >>> >> >> Is this a common pattern I can find in pharos classes. Or I need some >> help understanding this. The semaphore >> wait/signal is used instead of process resume/suspend? >> >> What I want is a process doing repeatly some computation, >> calls or triggers an update on a morph, and I want to suspend and resume >> this process. >> >> I would stop this discussion if someone tells me, "No your are doing it >> wrong, go this way ..", BUT what strikes me: >> in this example, that reproduces my problem more closely: >> >> |p m s running| >> running:=false. >> m:=Morph new color:Color red. >> s:= StringMorph new. >> m addMorphBack:s. >> p:=[[true]whileTrue:[20 milliSeconds asDelay wait. s >> contents:(DateAndTime now asString). m changed]] newProcess. >> m on:#mouseUp send:#value to:[ >> running ifTrue:[p suspend. m color:Color red.] >> ifFalse:[p resume.m color:Color green.]. >> running := running not]. >> m extent:(300@50). >> m openInWorld >> >> >> clicking on the morph will stop or resume the process, if it locks up I >> can still press alt+dot -> >> - a Debugger opens but the UI is still not responsive. I can click with >> the mouse on the debuggers close icon. >> - nothing happens, as the UI is still blocked. >> - pressing alt+Dot again, the mouse click on the close icon is >> processed and the first debugger window closes >> - maybe other debuggers open. >> >> Repeating this steps, at some time the system is *fully* responsive again! >> And miraculously, it works after that without further blockages. >> What's happening here? >> >> >> Nicolai >> >> >> >>> >>> HTH >>> >>> regards >>>> Nicolai >>>> >>> >>> >>> >>> -- >>> best, >>> Eliot >>> >> >> > >

July 23, 2014

Re: [Pharo-dev] transformmorph and submorph bounds

by Thierry Goubier

2014-07-23 8:00 GMT+02:00 Tudor Girba <tudor(a)tudorgirba.com>: > Hi, > > In GTInspector we use a TransformMorph inside the pager morph. It works > fine, but spawning completion from a text morph that is placed inside this > transform morph, the completion morphs appears in the wrong place. > > The issue comes from submorphBounds apparently not being right (this is > what the completion morph relies on). > > Here is a simpler example, to exemplify what I am talking about: > > circle := CircleMorph new. > morph := TransformMorph new. > morph addMorph: circle. > morph top: 100. > morph left: 100. > morph submorphBounds. "==> (100@100) corner: (140@140)" > circle submorphBounds. "==> (0@0) corner: (40@40)" > This seems correct to me: a transformMorph is the one which shift its contents (and reset the origin to its top left corner ?). Why do you use a TransformMorph there? Thierry > Ideally, "circle submorphBounds" should start at 100@100. Is this a bug, > or am I doing something wrong? > > Cheers, > Doru > > -- > www.tudorgirba.com > > "Every thing has its own flow" >

July 23, 2014

Re: [Pharo-dev] Doubt in Pharo

by Peter UhnÃ¡k

Hi, I'm sure someone can give a much better and more in-depth explanation but here goes: 1. Class side initialization is generally used to create fully functional objects. If you use just instance-side you might forget to set some important value (let's say ID) which would leave the object in invalid state. Another reason would be that it shows what does one really need to create a valid instance. If you have Empoyee class>>id: anId name: aName you will now know that salary is actually not needed and the object is able to cope with that. (And you can set it later). Yet another reason would be setting some additional/default values (however this can be done also internally on the instance-side). 2. Some elementary examples might be Rectangle or Point in Kernel > BasicObjects package. Generally you wouldn't send Employee message new directly, because that is class-side's job now, but rather you send the actual values: Employee id: 123 name: 'John Doe'. "answers with an Employee instance" Peter On Wed, Jul 23, 2014 at 8:33 AM, Dokania, Harshit <hdokani2(a)illinois.edu> wrote: > Hello, > > I am creating an Object Relational Mapper in pharo using sqlite. > > While creating database I am using a dictionary for columns of Database. > This gives me Keys as column name and values as Data type of those. > > So suppose Employee is the the table name, with ID->Integer, Name->Text, > Salary->Float. > > emp:= Employee new. > Now emp is a row of table, so for each row user has to create instance of > Employee and then feed values to it. Later on he can pass message insert > query to emp. > > So I was creating this dictionary for column at the instance side > initialization of Employee. > > My instructor suggested to do that in class side initialization, > > My Doubts are: > > 1. Why should we do class side initialization instead of instance side > initialization. > > 2. Could you please refer me to the link which explains how to do class > side initialization. Because when I do Employee new, I see only instance > side initialization is being called. > > Thanks, > Harshit > > >

July 23, 2014