- Pharo-users - lists.pharo.org

Re: [Pharo-users] Removing packages from a repository

by Sergio Fedi

Awesome, I could remove the spurious packages. Thanks! (these packages where made in the first iterations of the project when I didn't use correctly the package structure)

April 29, 2015

Re: [Pharo-users] STON references class removed in Pharo 5

by Jan BlizniÄenko

Thank you. I always like to try latest images, that's why I ask so early, and this change in image seemed like one which will not be reverted or changed again. Jan Sven Van Caekenberghe-2 wrote > Pharo 5 is only a couple of days old, but here you go (in #bleedingEdge): > > Sven -- View this message in context: http://forum.world.st/STON-references-class-removed-in-Pharo-5-tp4821773p48… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

April 29, 2015

Re: [Pharo-users] class initialization and class-side variables

by Jan BlizniÄenko

Thank you for sharing your experience with it. So, when I see all this, I think depending on initialize method on class side seems like a pretty bad idea. So I decided to leave this way of thoughts and I came up with lazy initialization. With lazy initialization it seems to work just fine and my problem is probably solved. mcz if you want: http://www.mediafire.com/download/c4jwmkz58mb4e9t/Something-bliznjan.7.mcz Thank you all for your help. Jan Ben Coman wrote > Each class needs its *own* initialize method. You can observe this > behaviour as follows... > > 1. Create a new package MyPlay holding the following... > > Object subclass: #SomeClass > > SomeClass class>>#initialize > self inform: 'Initializing... ' , self name. > > #SomeClass object: #SubClass "Notice that there was no inform message" > > 2. Export package to local disk using Monticello. > > 3. Delete MyPlay package. > > 4. Via Monticello load MyPlay package. > Observe that you only get an inform message for SomeClass, and not > SubClass. > > > I wanted to understand this behaviour more, so I modified... > > SomeClass class>>#initialize > self haltOnce. > self inform: 'Initializing... ' , self name. > > ...then enabled haltOnce and repeated steps 2, 3, 4 -- which broke out > from > MCMethodDefinition>>postloadOver: > which shows #initialize is only called on classes where #initialize is > defined. > > > So it seems that creating a new class does not call #initialize at all, > let > alone an inherited one. It is a Monticello behaviour. > > cheers -ben -- View this message in context: http://forum.world.st/class-initialization-and-class-side-variables-tp48228… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

April 29, 2015

Re: [Pharo-users] Pharo and Hadoop

by Ben Coman

And (as I've picked up listening to other conversations) with Sista doing hotspot optimisation *in-image* deployed images will be able to start hot rather than taking cycles to determine hot spots after startup. cheers -ben On Wed, Apr 29, 2015 at 9:55 PM, Esteban A. Maringolo <emaringolo(a)gmail.com> wrote: > Having Pharo playing there seems to be a good place to show its strengths. > > However, you mentioned too many acronyms of technologies I don't > understand (but hear a lot about). > > The only thing I can agree with is that the self-contained nature of > Pharo is a true advantage when deploying extra nodes. It's not only > fast, but also pretty lightweight compared with behemoths such as > Java. > > Regards, > > Esteban A. Maringolo > > > 2015-04-29 9:57 GMT-03:00 phil(a)highoctane.be <phil(a)highoctane.be>: > > I am involved in some Hadoop deployments and there is a very interesting > > possiblity for Pharo in that ecosystem. > > > > Namely, there is a YARN thing in there which is a scheduler for > distributing > > computing on a cluster of nodes. > > > > It is possible to deploy all kinds of technologies on the nodes (e.g. > > Python, R, Java) and Pharo images and VM (in headless mode) could be > > deployed as well. > > > > The deployed node can communicate back to what is called an > > AppllicationManager via REST callbacks (easy game in Pharo). There is > also a > > C API (now, this is FFI or a plugin - > > http://zookeeper.apache.org/doc/trunk/zookeeperProgrammers.html) > > > > There is also an Hadoop component named ZooKeeper that focuses on acting > as > > a distributed configuration repository. > > > > One can talk to it with REST too > > (https://github.com/apache/zookeeper/tree/trunk/src/contrib/rest) > > > > Given the fact that we also can use some Java calls (using the JNI module > > with 32-bits Java), we can integrate well enough on YARN I'd say. > > > > There is also another project which is very nice and this is SLIDER (on > > YARN). > > This is about deploying stuff in an elastic way, (see > > http://slider.incubator.apache.org/) > > > > The next logical thing is to have docker containers (containing a pharo > > stack) deployed dynamically on the cluster using Slider (like this: > > http://www.slideshare.net/hortonworks/docker-on-slider-45493303) > > > > First step here would be to have a basic YARN-Pharo application and a PoC > > for talking to ZooKeeper. > > > > This would open interesting gates for Pharo given its strengths. > > Even more when we'll get a 64-bit VM. > > > > What is cool with Pharo is that an image can be very small and self > > containing vs Java application (which have tons of Jar files attached). > > > > Access to the data on the HDFS thing can happen through NFSv3 so, we can > go > > that route. > > There is also a REST API to it > > (https://hadoop.apache.org/docs/r1.0.4/webhdfs.html) > > > > Tell me what you think! > > > > Phil > > > >

April 29, 2015

Re: [Pharo-users] class initialization and class-side variables

by Ben Coman

Each class needs its *own* initialize method. You can observe this behaviour as follows... 1. Create a new package MyPlay holding the following... Object subclass: #SomeClass SomeClass class>>#initialize self inform: 'Initializing... ' , self name. #SomeClass object: #SubClass "Notice that there was no inform message" 2. Export package to local disk using Monticello. 3. Delete MyPlay package. 4. Via Monticello load MyPlay package. Observe that you only get an inform message for SomeClass, and not SubClass. I wanted to understand this behaviour more, so I modified... SomeClass class>>#initialize self haltOnce. self inform: 'Initializing... ' , self name. ...then enabled haltOnce and repeated steps 2, 3, 4 -- which broke out from MCMethodDefinition>>postloadOver: which shows #initialize is only called on classes where #initialize is defined. So it seems that creating a new class does not call #initialize at all, let alone an inherited one. It is a Monticello behaviour. cheers -ben On Wed, Apr 29, 2015 at 8:25 PM, Jan BlizniÄenko <bliznjan(a)fit.cvut.cz> wrote: > Hello > > It seems I misunderstood some concept of classes in Pharo. My problem is > following: > Let's say I have class named SomeClass (subclass of Object) and class named > SubClass (subclass of SomeClass). > > If I create instance variable on SomeClass and SomeClass>>#initialize which > initializes the variable, it gets initialized also when SubClass instance > is > created. > > Now I'm trying to do something similar for class-side variables, but with > no > success. > If I create class-side variable on SomeClass and SomeClass > class>>#initialize which initializes the variable, it gets initialized only > in SomeClass class, but not in SubClass class. > > What I mean: > > Object subclass: #SomeClass > > SomeClass class > instanceVariableNames: 'Ok' > > SomeClass class>>#initialize > super initialize. > Ok := true > > SomeClass class>>#isOk > ^ Ok > > SomeClass subclass: #SubClass > > calling "SomeClass isOk" returns true. > calling "SubClass isOk" returns nil. > > > now If I create method > > SubClass class>>#initialize > super initialize. > > SubClass initializes as I would expect from my experience with instance > initialization, so "SubClass isOk" now returns true. > > > I will appreciate any help. > > Jan > > > > -- > View this message in context: > http://forum.world.st/class-initialization-and-class-side-variables-tp48228… > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. > >

April 29, 2015

Re: [Pharo-users] Pharo and Hadoop

by Esteban A. Maringolo

Having Pharo playing there seems to be a good place to show its strengths. However, you mentioned too many acronyms of technologies I don't understand (but hear a lot about). The only thing I can agree with is that the self-contained nature of Pharo is a true advantage when deploying extra nodes. It's not only fast, but also pretty lightweight compared with behemoths such as Java. Regards, Esteban A. Maringolo 2015-04-29 9:57 GMT-03:00 phil(a)highoctane.be <phil(a)highoctane.be>: > I am involved in some Hadoop deployments and there is a very interesting > possiblity for Pharo in that ecosystem. > > Namely, there is a YARN thing in there which is a scheduler for distributing > computing on a cluster of nodes. > > It is possible to deploy all kinds of technologies on the nodes (e.g. > Python, R, Java) and Pharo images and VM (in headless mode) could be > deployed as well. > > The deployed node can communicate back to what is called an > AppllicationManager via REST callbacks (easy game in Pharo). There is also a > C API (now, this is FFI or a plugin - > http://zookeeper.apache.org/doc/trunk/zookeeperProgrammers.html) > > There is also an Hadoop component named ZooKeeper that focuses on acting as > a distributed configuration repository. > > One can talk to it with REST too > (https://github.com/apache/zookeeper/tree/trunk/src/contrib/rest) > > Given the fact that we also can use some Java calls (using the JNI module > with 32-bits Java), we can integrate well enough on YARN I'd say. > > There is also another project which is very nice and this is SLIDER (on > YARN). > This is about deploying stuff in an elastic way, (see > http://slider.incubator.apache.org/) > > The next logical thing is to have docker containers (containing a pharo > stack) deployed dynamically on the cluster using Slider (like this: > http://www.slideshare.net/hortonworks/docker-on-slider-45493303) > > First step here would be to have a basic YARN-Pharo application and a PoC > for talking to ZooKeeper. > > This would open interesting gates for Pharo given its strengths. > Even more when we'll get a 64-bit VM. > > What is cool with Pharo is that an image can be very small and self > containing vs Java application (which have tons of Jar files attached). > > Access to the data on the HDFS thing can happen through NFSv3 so, we can go > that route. > There is also a REST API to it > (https://hadoop.apache.org/docs/r1.0.4/webhdfs.html) > > Tell me what you think! > > Phil >

April 29, 2015

Re: [Pharo-users] class initialization and class-side variables

by Sean P. DeNigris

Jan BlizniÄenko wrote > Only way to aquire it seems to create initialize method in every subclass > class Maybe initialize all subclasses from the parent? But you'd have to reinitialize if you added more subclasses later... ----- Cheers, Sean -- View this message in context: http://forum.world.st/class-initialization-and-class-side-variables-tp48228… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

April 29, 2015

Re: [Pharo-users] class initialization and class-side variables

by Jan BlizniÄenko

Replying to myself... Here is example package with tests of behavior I expect: http://www.mediafire.com/download/bjmt7p20ndcgddf/Something-bliznjan.6.mcz Only way to aquire it seems to create initialize method in every subclass class, and write just "super initialize" there, but for about 30 subclasses (and many more in the future), it does not seem like fine solution. Jan Jan BlizniÄenko wrote > Thank you both for reply. Unfortunately, it seems I didn't describe my > goal well. > > I want both (all) classes to have separate variables, not shared among > subclasses, but still initialized on class side, not instance side. So I > want those variables to be class-side variables, my problem is with their > initialization. I have a tree of classes, top class (superclass of the > rest) should have class-side variable initialized as empty collection, and > almost all it's subclasses to have, by default, also an empty colletion. > But there will be few classes in this tree, whose collections should > contain something. > > So to return to my previous example... I want SomeClass class-side > variable "SomeCollection" to contain OrderedCollection()... SubClass along > with many more subclasses to also contain OrderedCollection... but also to > have a SpecificSubClass, whose class-side variable "SomeCollection" will > contain OrderedCollection(something, somethingElse...). > > Jan > Sean P. DeNigris wrote >> What you created is a class-side instance variable, which is private to >> just that class. What you want is a class variable, which is shared by >> all subclasses and instances. You declare it in the class definition with >> #classVariableNames:. There is a very nice explanation of these basic >> (but confusing!) concepts in the "Pharo By Example" book. > > Andrei Chis wrote >> Hi, >> >> SomeClass and SubClass are two different objects. >> Based on your setup, if you do not call any initialize method, initially >> calling both "SomeClass isOk" and "SubClass isOk" should return nil. >> >> Running "SomeClass initialize" initializes only the SomeClass object. So >> now "SomeClass isOk" returns true and "SubClass isOk" returns nil, as >> its >> another object that has not been initialized. >> You get the same behaviour if you first call "SubClass initialize". >> Now "SomeClass >> isOk" returns nil because you did not initialize the SomeClass object, >> but >> the SubClass. >> >> Even if you add initialize in the SubClass class and call it first >> "SomeClass >> isOk" will still return false. >> SomeClass and SubClass are just two different objects of types SomeClass >> class and SubClass class. It's the same behaviour that you get when you >> create two instances of these classes. Just because you create an >> instance >> of the type SubClass and call super initialize, >> it doesn't mean that another instance of SomeClass will be initialized. >> >> Hope this makes sense/answers your question. >> >> Cheers, >> Andrei -- View this message in context: http://forum.world.st/class-initialization-and-class-side-variables-tp48228… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

April 29, 2015

Re: [Pharo-users] class initialization and class-side variables

by Andrei Chis

Aha, now I understand your question. >From what I remember #initialize might only be send to classes if they contain an explicit initialize method, but I might remember wrongly. Cheers, Andrei On Wed, Apr 29, 2015 at 3:08 PM, Jan BlizniÄenko <bliznjan(a)fit.cvut.cz> wrote: > Thank you both for reply. Unfortunately, it seems I didn't describe my goal > well. > > I want both (all) classes to have separate variables, not shared among > subclasses, but still initialized on class side, not instance side. So I > want those variables to be class-side variables, my problem is with their > initialization. I have a tree of classes, top class (superclass of the > rest) > should have class-side variable initialized as empty collection, and almost > all it's subclasses to have, by default, also an empty colletion. But there > will be few classes in this tree, whose collections should contain > something. > > So to return to my previous example... I want SomeClass class-side variable > "SomeCollection" to contain OrderedCollection()... SubClass along with many > more subclasses to also contain OrderedCollection... but also to have a > SpecificSubClass, whose class-side variable "SomeCollection" will contain > OrderedCollection(something, somethingElse...). > > Jan > > > Sean P. DeNigris wrote > > What you created is a class-side instance variable, which is private to > > just that class. What you want is a class variable, which is shared by > all > > subclasses and instances. You declare it in the class definition with > > #classVariableNames:. There is a very nice explanation of these basic > (but > > confusing!) concepts in the "Pharo By Example" book. > > > Andrei Chis wrote > > Hi, > > > > SomeClass and SubClass are two different objects. > > Based on your setup, if you do not call any initialize method, initially > > calling both "SomeClass isOk" and "SubClass isOk" should return nil. > > > > Running "SomeClass initialize" initializes only the SomeClass object. So > > now "SomeClass isOk" returns true and "SubClass isOk" returns nil, as > its > > another object that has not been initialized. > > You get the same behaviour if you first call "SubClass initialize". > > Now "SomeClass > > isOk" returns nil because you did not initialize the SomeClass object, > > but > > the SubClass. > > > > Even if you add initialize in the SubClass class and call it first > > "SomeClass > > isOk" will still return false. > > SomeClass and SubClass are just two different objects of types SomeClass > > class and SubClass class. It's the same behaviour that you get when you > > create two instances of these classes. Just because you create an > instance > > of the type SubClass and call super initialize, > > it doesn't mean that another instance of SomeClass will be initialized. > > > > Hope this makes sense/answers your question. > > > > Cheers, > > Andrei > > > > > > -- > View this message in context: > http://forum.world.st/class-initialization-and-class-side-variables-tp48228… > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. > >

April 29, 2015

Re: [Pharo-users] Understanding Slices

by Ben Coman

Someone correct me - any package can have a dependent package added. We just don't do that (I've never seen it my past couple of years with Pharo). A Slice is simply an empty package that has dependencies. Now it seems somewhat tied to development of the Pharo image since it requires an issue number - but I guess you could use it for other purposes with any random issue number or 00000. cheers -ben On Wed, Apr 29, 2015 at 8:18 PM, Sean P. DeNigris <sean(a)clipperadams.com> wrote: > Sergio Fedi wrote > > Are Slices a way to represent a change accross packages? > > Exactly. In the MC browser, there is a button to create a slice from an > issue number. During that workflow, you will be asked to select all > relevant > packages. When the slice is committed or loaded, it will bring all of those > packages with it. > > > > ----- > Cheers, > Sean > -- > View this message in context: > http://forum.world.st/Understanding-Slices-tp4822860p4822867.html > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. > >

April 29, 2015