July 2012 - Pharo-users - lists.pharo.org

Dynamic graph exploration - seeking input on idiomatic smalltalk [LONG]

by Patrik Sundberg

Hi, First of all, sorry for the long email as my first email to the list. Hopefully some people will find it an interesting discussion :) I'm a long time programmer that has been studying smalltalk and pharo over the last year. It's a beautiful language I'm liking the image style of development a whole lot. I've been looking for a good test case to try out in pharo and I've got something in mind. I've used ruby since around 2000 and given how much it has been inspired by smalltalk it's not a big leap. My real job is being a commodities trader but I build my own tools and something I'm always working on is improved risk and pricing tools. Lots of that comes down to 2 things: 1. evaluating a "function" (in a general sense) with inputs that are picked depending on time. e.g. I want to price a security and I want to pick up prices for time X as inputs to the pricing model. 2. calculating a derivative of the "function" above with respect to inputs What I tend to do in order to keep things consistent by design, plus add natural caching, is create a calculation graph. I define all the dependencies and create an in-memory graph where each node is unique using an identity map. I then perform a calculation where the calculations trickle down the graph starting from the node I'm interested in down all it's dependencies. To calculate the derivative I then find the node representing the input I want the derivative with respect to and use finite differences, e.g. move it's value, and recalculate the top level node. On the second valuation of the graph only the parts that are affected by me changing that 1 value will need to be evaluated, the rest is cached an unaffected. It makes it very easy to ask questions like "How much will I be affected by X changing by Y?" since I can take the top level node of the graph, search for X, and if found change it by Y and recalculate. How the graph is constructed in memory depends on time (and a few other things). I always store all previous states of the world so that I can recreate any calculation I did in the past. Very useful for diagnosing problem. Hence if I for example change what model I use to model something, that change is recorded in a way such that if I set my "time" to before the change happened the graph will get created as it would have with the old model, and for a time after the change it'll create a different graph reflecting the new model. Hence the graph can only be known at runtime when the "time" etc is known. I currently have a ruby mockup of this. It's a DSL that looks like this: ----------- EXAMPLE class ExampleObject include GraphEntity # includes a module with functionality for objects participating in the graph, including #property and #calc used below property :foo do 123 # this is the default value for this property which will be used before a value has been set and saved end calc :bar do |arg| foo.value + arg # take the value of the arg property and add the argument given to the calculation node end end o = ExampleObject.new # this will kick of the graph being built in memory and setup the dependency between bar and foo nodes o.bar(1).value # -> 124 # this will be a "cache lookup" since nothing in the graph that bar depends on has changed (i.e. the "expensive" calculation is not performed again o.bar(1).value # -> 124 o.foo.set_value(2) o.bar(1).value # -> 125, realizes that foo changed and performs a recalc -------------------------------------------------------- To accomplish this I use dynamic code generation like the below for #property and similar for other types of nodes: # NOTE: it's a class level method, hence how I can call it when defining the class in the example def property(name, time = CdrEnv.instance.time, &block) clear_property(name) getter_method_body = <<-EOF def #{name} init_block = self.class.property_init_block_for(:#{name}) time_for_property = self.class.property_time_dependency_for(:#{name}) if init_block.nil? CdrEnv.instance.get_property_node(self, :#{name}, time_for_property) else CdrEnv.instance.get_property_node(self, :#{name}, time_for_property, &init_block) end end EOF setter_method_body = <<-EOF def #{name.to_s}=(value) #{name.to_s}.mutate(value) end EOF class_eval getter_method_body class_eval setter_method_body register_property_node(name, time, &block) end Don't worry about the details or all the unfamiliar ruby, the main point is that it creates an instance method that uses the singleton CdrEnv.instance to either get or create the node representing the property from the graph identity cache depending on if it exists or not. >From a tooling point of view I think I'd love to work with this kind of thing in pharo. Building my own browsers for inspecting and debugging my dynamic graph should be very good fit. However, I'd appreciate some pointers to idiomatic smalltalk to attack this kind of problem in terms of implementing the graph itself - I obviously want the user (even if it's me) to just have to focus on the domain model and hide as much as possible of the graph bits under the covers the same way I've done with the code generation stuff in my ruby example. Any input into this would be much appreciated, Patrik P.S. Btw, the persistence backend for this is the neo4j graph database, but it's fronted by a service slotting into my own service framework built using ZeroMQ and services exchanging messages in protobuf format. One can use it from any language as long as one can send protobuf messages over zeromq. I see there's a zeromq ffi library available on SS that I'll check out, but I'm not finding a protobuf implementation. It'd be easy enough for me to port a ruby protobuf implementation but I may as well ask if someone has already done any work on protobuf for smalltalk? -- View this message in context: http://forum.world.st/Dynamic-graph-exploration-seeking-input-on-idiomatic-… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

July 6, 2012

update on the consortium poll

by StÃ©phane Ducasse

Hi pharoers Here is so far the state of replies I compiled. If I miss you or misclassified tell me. By end of July I will build a case to ask for INRIA support. So I will refresh this list and group mails to build a convincing case. Pharo2.0 is going in the right direction. With a mini core, vector graphics, ssh, it is starting to be a nice platform for new challenges. Thanks you all for your trust. Stef So far 4000 gold 8000 silver 5000 bronze 500 sponsor 2500 individual plus 480 individual -------------------- 20480 Euros Gold (4000) RMOD 4000 Silver (2000) 2Denker http://www.Synectique.eu Sanders Cameron company 2Rivers 8000 Bronze (1000) Andy bunnett company Eggermont company MAD-Environment www.FinWorks.biz netStyle.ch 5000 Sponsors (500) Caeasar Systems (May be IMUS)?? 500 Indivudual golden (100) Stephane Ducasse Marcus Denker Schmiedl Miguel Coba Alexandre Bergel Krish Brodbeck (may be bronze) Goran Vasic Guillermo Polito Norbert Harlt Mark Smith Lorenzo schiavina Daniel Galdames Leandro Caniglia Francois Stephany Sean De Nigris John O'Keefe Tudor Girba Luc Fabresse Florent Arrignon Lawrence Trutter Sabine Knofel Yann Monclair Henrik Johanssen Hernan Wilkinson (or bronze to be defined) 2500 Normal 40 Bill schwab Herve verjus Damien cassou McLeod Max Leske Phil Back (bronze may be) Yanni Chiu Andrea BrÃ¼hlmann Stefan Reichhart Niklaus Lutz Max Leske Simon Jakovina 480

July 5, 2012

Re: [Pharo-users] PluggableMultiColumnListMorph broken?

by Benjamin

We have introduced a dispatch in the list, allowing every kinds of object to be displayed if the provide the good interface. Right now, this interface is provided by String, Text, and Morph. On the other hand, the PluggableMultiColumnListMorph is designed to take "real" object as entry, and then the wrapping method is used to specify how to split the object into multiple columns. And by default, the wrappingMethod returns the printString of the object. So in your case, the elements (which are collections) are turned into a String like '#('a' 'b' c')', and when the list iterates over the object, it iterates on characters. Maybe the default behavior should be changed, because if you do not precise, it will hangs. To fix your example, you can do PluggableMultiColumnListMorph on: self list: #actorMultiList selected: nil changeSelected: nil menu: nil keystroke: nil wrapSelector: #wrap: wrap: item ^ item Note that the result will be a b c d 1 2 3 4 alpha 20 beta gamma The list provides rows, not columns anymore Ben On Jul 3, 2012, at 5:50 AM, Jeff Gray wrote: > Is PluggableMultiColumnListMorph broken in 1.4? > > If I have a very simple case within a polymorph window: > > PluggableMultiColumnListMorph on: self list: #actorMultiList selected: nil > changeSelected: nil menu: nil keystroke: nil wrapSelector: nil > > and the actorMultiList method is: > ^ #(('a' 'b' 'c' 'd') ('1' '2' '3' '4') ('alpha' '20' 'beta' 'gamma')) > > then I get the following error: Character(Object) doesNotUnderstand: > #widthToDisplayInList: > > > > -- > View this message in context: http://forum.world.st/PluggableMultiColumnListMorph-broken-tp4637828.html > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. >

July 3, 2012

PluggableMultiColumnListMorph broken?

by Jeff Gray

Is PluggableMultiColumnListMorph broken in 1.4? If I have a very simple case within a polymorph window: PluggableMultiColumnListMorph on: self list: #actorMultiList selected: nil changeSelected: nil menu: nil keystroke: nil wrapSelector: nil and the actorMultiList method is: ^ #(('a' 'b' 'c' 'd') ('1' '2' '3' '4') ('alpha' '20' 'beta' 'gamma')) then I get the following error: Character(Object) doesNotUnderstand: #widthToDisplayInList: -- View this message in context: http://forum.world.st/PluggableMultiColumnListMorph-broken-tp4637828.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

July 3, 2012

Re: [Pharo-users] Problem with the installation of Magritte

by Olivier Auverlot

okâ¦ Thanks Olivier Le 2 juil. 2012 Ã 12:03, Esteban Lorenzano a Ã©crit : > yes, because Lukas site is down > > On Jul 2, 2012, at 11:23 AM, Olivier Auverlot wrote: > >> Hi, >> >> I'm trying to install Magritte in a image of Pharo 1.4 with Nautilus and Seaside. I'm using the following commands : >> >> Gofer new >> squeaksource: 'MetacelloRepository'; >> package: 'ConfigurationOfMagritte2'; >> load. >> >> ((Smalltalk at: #ConfigurationOfMagritte2 ) project latestVersion) load >> >> But this fails with the error : "Could not resolve: Magritte-Model" >> >> Any idea ? >> >> Best regards >> Olivier :) > >

July 2, 2012

Re: [Pharo-users] Problem with the installation of Magritte

by Esteban Lorenzano

yes, because Lukas site is down On Jul 2, 2012, at 11:23 AM, Olivier Auverlot wrote: > Hi, > > I'm trying to install Magritte in a image of Pharo 1.4 with Nautilus and Seaside. I'm using the following commands : > > Gofer new > squeaksource: 'MetacelloRepository'; > package: 'ConfigurationOfMagritte2'; > load. > > ((Smalltalk at: #ConfigurationOfMagritte2 ) project latestVersion) load > > But this fails with the error : "Could not resolve: Magritte-Model" > > Any idea ? > > Best regards > Olivier :)

July 2, 2012

Problem with the installation of Magritte

by Olivier Auverlot

Hi, I'm trying to install Magritte in a image of Pharo 1.4 with Nautilus and Seaside. I'm using the following commands : Gofer new squeaksource: 'MetacelloRepository'; package: 'ConfigurationOfMagritte2'; load. ((Smalltalk at: #ConfigurationOfMagritte2 ) project latestVersion) load But this fails with the error : "Could not resolve: Magritte-Model" Any idea ? Best regards Olivier :)

July 2, 2012

Re: [Pharo-users] [Esug-list] **IMPORTANT** MUST READ: Pharo Association and Consortium

by Tudor Girba

Hi, I will become a personal golden member (99EUR/year), too. Cheers, Doru On 30 Jun 2012, at 09:37, Marcus Denker wrote: > > On Jun 28, 2012, at 2:19 PM, StÃ©phane Ducasse wrote: >> >> ===================== >> *** Support and Answer needed*** >> ===================== >> >> To be able to pay an engineer by the consortium, INRIA needs to make projection, build budget, pay attention to visa >> and other important administrative tasks. To deal with the risk that the consortium may not collect enough to pay a full salary >> we are considering to ask INRIA to help us financially. To do so we have to give some concrete figures to >> INRIA and motivate our request. In addition, our team (RMOD) on its own budget will try to compensate by allocating extra resources >> However, this will be only a one shot. In addition, some of our team members have been approached by google to work on chrome and dart >> Virtual Machines. So if we really get a future we should build it now. >> > > I will be a personal golden member (99EUR/year) > > And with Norbert and Christian, we decided that http://2denker.de (2Denker GmbH) will be a Silver Member of the consortium. > > Marcus > > -- > Marcus Denker -- http://marcusdenker.de > > > _______________________________________________ > Esug-list mailing list > Esug-list(a)lists.esug.org > http://lists.esug.org/mailman/listinfo/esug-list_lists.esug.org -- www.tudorgirba.com "In a world where everything is moving ever faster, one might have better chances to win by moving slower."

July 1, 2012

Re: [Pharo-users] Versionner a GUI for metacello

by StÃ©phane Ducasse

***EXCELLENT*** I want to play with it. I really want to invest on it and build a tools to manage configurations. Thanks! On Jul 1, 2012, at 5:46 AM, Juan Pablo Sandoval Alcocer wrote: > Hi All, > > I worked today day :) in Versionner. I updated the website http://users.dcc.uchile.cl/~jsandova/versionner/ > > Here the install instructions for Versionner (Spec version as default) > -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= > Gofer new > url: 'http://ss3.gemstone.com/ss/Versionner'; > package: 'ConfigurationOfVersionner'; > load. > (Smalltalk at: #ConfigurationOfVersionner) perform: #load > -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= > > If you had installed previous versions of "Versionner". I strongly suggest uninstall the previous version before to install the last version. > > Juan Pablo > > 2012/6/30 StÃ©phane Ducasse <stephane.ducasse(a)inria.fr> > juan pablo > > could you release the spec version of versioner because we will not load glamour in 2.0 core > but spec is there so we will add spec versioner version. > > Stef > > > On Jun 30, 2012, at 2:49 AM, Juan Pablo Sandoval Alcocer wrote: > > > Hi Sean, > > > > Thank you for your support, I updated the configuration of Versionner with your enhancements. > > > > I updated the install instructions in the web page http://users.dcc.uchile.cl/~jsandova/versionner/install.html. > > > > Regards, > > Juan Pablo > > > > > > 2012/6/29 DeNigris Sean <sean(a)clipperadams.com> > > I made a few enhancements to ConfigurationOfVersionner: > > * allowing it to load (development version) on 2.0 > > * fixing it for the new Metacello bootstrap, which no longer loads the Toolbox > > > > ConfigurationOfVersionner-SeanDeNigris.63 > > * Update for new Metacello bootstrap (no longer loads by default > > - Add 'Metacello Toolbox' project to baseline 1.2 > > - Add 'Metacello Toolbox' as a dependency of Versionner-Core-Model > > * Fix for Pharo 2.0 - Use #'development' version of 'Glamour for Versionner' > > * Tiny refactor of loadWithGlamour to send #stableVersion instead of "version: #stable" > > > > > > > > > > -- > > Juampi > > > > > > -- > Juampi

July 1, 2012

Re: [Pharo-users] I need the help of a guru about squeezeOutNumber

by Sven Van Caekenberghe

On 01 Jul 2012, at 02:15, Benjamin wrote: > We figured out today that > > 'blabla1230' squeezeOutNumber ==> 123 > > But it should be 1230. > > So after multiple attempts to debug this expression (with strange behaviors), we discovered that it's while parsing the reversed version of the string that it fails[1] > Indeed, when reversed, the trailing 0 become a leading 0, and is ignored (which in our case is wrong). > > So we removed this part, and all the tests are green again. > But still we were wondering if the piece of code is needed somewhere or not ? You made it simpler and the tests succeed, ergo it is better. Is this needed/necessary, that is another question. I would guess that the reversing was a kind of optimization. > Thanks in advance, > Ben and Cami > > > > [1]:squeezeNumberOutOfString: stringOrStream onError: errorBlock > "Try and find a number in this string. First, look if the string > starts with a number. Then, see if it ends with a number. Then, > remove a character from the front and see if the remaining > string makes a number. Repeat the process until no characters > are left or the number has been found. As soon as a number is > found, it is returned. Otherwise, the method fails." > > | string try | > > stringOrStream isEmpty ifTrue: errorBlock. > > (self parse: stringOrStream onError: [nil]) > ifNotNilDo: [:result | ^ result ]. > > (self parse: stringOrStream asString copy reversed onError: [nil]) > ifNotNilDo: [:result | ^ result asString reversed asNumber]. > > string := stringOrStream. > "We do the loop n-1 times because at the n-th iteration, string is empty" > (stringOrStream size -1) timesRepeat: [ > string := string allButFirst. > (self parse: string onError: [ nil ]) > ifNotNilDo: [ :result| ^ result ].]. > > ^ errorBlock value

July 1, 2012