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

iterating through an ascii file by line
by Paul DeBruicker Aug. 3, 2012

Aug. 3, 2012

Hi - Is there an easy/standard way to open an ascii file and iterate through it line by line? I want to put several files contents into their own OrderedCollections and then do awful things to them. The files are ~500MB each Thanks Paul

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How do you guys navigate while editing code?
by Patrik Sundberg Aug. 1, 2012

Aug. 1, 2012

Hi, Jumping in as a smalltalk beginner I am, as one would expect, feeling frustrated by not knowing my way around. Can see lots of cool stuff but all the mouse action is killing me. I'm a vim(+tmux) guy by background so the contrast is vast, I usually never need to touch my mouse when programming. I was trying to find some keyboard shortcuts to do things like "jump to method within class with fuzzy search logic" (type a few characters and get list etc) or "jump to the method/class under which the cursor is located". The jump to selected needs text selection which seems really awkward (even when selecting with keyboard), my 90% case is to jump to what's under the cursor. The global find class and find methods are good, but most of the time I'm interested in "local" navigation in the current class while jumping back and forth between methods in same class. I find more things in Nautilus since I can list the shortcuts there, but quite a few doesn't seem to work and I'm not having much luck using nautilus in 1.4 (and 2.0 too edgy for me right now, need metacello to load things cleanly etc at least). In OB in 1.4 I'm not able to figure out how to get a list of shortcuts apart from what's annotated in menus Guess my question is - how does a keyboard centric person like me learn keyboard shortcuts and get productive in the image, more specifically 1.4 and OB? How can I work out what keyboard shortcuts exist? Thanks!

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Adding Websocket support to Zinc
by Andy Burnett July 31, 2012

July 31, 2012

I think we need Websocket support built into Pharo. So, rather than talk about it, I have contracted with Sven to build it into Zinc. We hope to have a running version in the early Autumn. The purpose of this email is: 1. To let everyone know that we will have Websocket support soon 2. To ask if anyone else feels that they would gain commercial benefit from using this feature, and if so, whether they would like to help cover the cost. If so, please drop me an email. Cheers Andy

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[pharo 2.0] IP address to ByteArray
by Bernardo Ezequiel Contreras July 31, 2012

July 31, 2012

Hi all, Is there a better way to convert an IP address to a ByteArray? I'm doing this ('127.0.23.11' subStrings: '.') collect: [:each | each asInteger ] as: ByteArray thanks -- Bernardo E.C.

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Re: [Pharo-users] [Pharo-project] fuelized test failures
by Mariano Martinez Peck July 25, 2012

July 25, 2012

And here I wrote what we are doing so that others know :) http://marianopeck.wordpress.com/2012/07/25/reviving-ci-test-failures-in-lo… Thanks Cami and Sean. You rock. Cheers, On Wed, Jul 25, 2012 at 6:45 AM, Camillo Bruni <camillobruni(a)gmail.com>wrote: > > On 2012-07-25, at 00:50, Sean P. DeNigris wrote: > > > > > Mariano Martinez Peck wrote > >> > >> but if that allows me to have the .fuel > >> files for each version, then please go ahead :) > >> > > > > The zip artifact now includes all the fuel files. I didn't add the fuel > > files as separate artifacts because it seems there's no way to specify a > > target folder for artifacts without a plugin. > > perfect guys! > > -- Mariano http://marianopeck.wordpress.com

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Dynamic graph exploration - seeking input on idiomatic smalltalk [LONG]
by Patrik Sundberg July 24, 2012

July 24, 2012

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.

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Recovery log thoughts
by Chris July 23, 2012

July 23, 2012

One area I see some beginners struggle with image development is with regards to losing work, and I feel that Pharo's recovery log could be improved to help with this. Two scenarios that come to mind are firstly where methods are filed in that created an instance variable at method save the first time round. These log to the transcript that the variable is now undeclared, but that can go unseen, and the result is things appearing to work while you only have one instance of that object. Could this bring up a similar prompt maybe? Another difficulty is that you can not simply file in all selections as any do-it's which were done in a different context will fail. Is there any way we can differentiate the important do-it's such as class definitions, selector removes and so on from the rest? Regards, Chris

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The opposite of encodeForHTTP
by Davide Varvello July 22, 2012

July 22, 2012

Hi there, Does exist the opposite method of String>>encodeForHTTP somewhere? TIA Davide -- View this message in context: http://forum.world.st/The-opposite-of-encodeForHTTP-tp4640491.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

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WaveFront File importer on Pharo
by Jean Baptiste Arnaud July 21, 2012

July 21, 2012

Hi, Under the pressure of Camillo i publish the code. I beginning to do a Wavefront (human readable standard for 3d Obj Model ) importer on Pharo. So i made a importer. Not all the case are manage, only the case I need to import the current Obj model. And a drawer which is in Alpha version. face and normal vector are manage. Missing color (in progress), and texturing. You need .obj file and all the .mtl related (open you blender and make it nice). If you are not running on Mac os comment this code in GLWorldTest>>#render, the display makeCurrent. else if you running on mac os implement it in NBMSAAOffscreenDisplay>>#makeCurrent ^driver makeCurrent. My code can be find on JBARepo on squeaksource ObjModel Package but you need NBOpenGL (i do a configuration in same place i just need to be motivated for keep it up to date). So put on same folder of the .image your .obj and .mtl file (i am lazy) (maybe it is VM folder i do not know). open a workspace and do "s := ObjImporter importFrom: 'xwing-map.obj'. s parse. object := s objects. w := GLWorldTest new. object do: [:e | w addElement: e]. w openInWorld." 3d result with normal With normal and color but not texture : Enjoy Best Regards Jean Baptiste Arnaud jbaptiste.arnaud(a)gmail.com

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[ANN] humane assessment / moose courses
by Tudor Girba July 21, 2012

July 21, 2012

Hi, Humane assessment is a method for making software engineering decisions. Assessing software systems to make decisions is a critical activity that needs to be approached explicitly during development. Humane assessment is made possible by the Moose analysis platform. I am organizing a couple of courses in Bern that might be of interest to people on this list: Humane Assessment Primer (August 17) - This course is relevant for both managers and engineers. It covers assessment economics and the means to integrate humane assessment in the development process and in the organization - http://www.humane-assessment.com/courses/humane-assessment-primer Moose Apprentice (September 6-7) - This course is relevant for engineers. This is an introductory hands-on course on using the Moose analysis platform for putting humane assessment into practice - http://www.humane-assessment.com/courses/moose-apprentice If you are interested in participating, please contact me directly. Cheers, Doru -- www.tudorgirba.com "In a world where everything is moving ever faster, one might have better chances to win by moving slower."

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