April 2016 - Pharo-users - lists.pharo.org

Pharo-users Question about the symbols
by Valentin Ryckewaert April 14, 2016

April 14, 2016

Hello everyone, i'm learning Pharo and i'm having difficulties to understand the symbols, what are they? How are they different of the ByteString ? Why are they usefull ? Why should I put #string where I can put 'string' ? Thanks in advance for your answer. Valentin Ryckewaert

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[ANN] General WebBrowser package for Pharo4 and Pharo 5 onwards
by Torsten Bergmann April 14, 2016

April 14, 2016

Hi, Some of you may know or use "ExternalWebbrowser" (maintained in the past by me, started back in the times right after Squeak and based on FFI), also there was an "ExternalWebbrowser2" fork from Sean later. First project got outdated with transition to NB, the second one stopped working for Pharo 5 due to the transition from NativeBoost (NB) to Universal Foreign Function Interface (UFFI). Two projects and now the broken code created a little bit a mess again in finding an easy way in opening an external webbrowser from Pharo. Updating my "ExternalWebbrowser" would easily bring confusion to newbies who thing "ExternalWebbrowser2" is newer. Having a an "ExternalWebbrowser3" would be silly too. So I decided to fix all this by providing a general "WebBrowser" package which now should solve the issue of easily opening an external webbrowser once and for all for primary platforms (Unix/Mac/Windows). The simple design allows to add also other platforms later if necessary. I based it for Pharo 4 on NB and Pharo 5 onwards on the new UFFI - so YES you can use it in both Pharo versions uniformely and the same way - which should simplify things now again. # Project page/Repository http://www.smalltalkhub.com/#!/~TorstenBergmann/WebBrowser # Description General and platform independent WebBrowser access for Pharo 4.0 onwards based on NativeBoost, for Pharo 5.0 onwards based on UFFI - Mac - Unix (Linux flavours) - Windows # Usage WebBrowser openOn: 'http://www.pharo.org' # Installation You can load it either from Configuration Browser (Pharo 4), Catalog/directly by typing "WebBrowser" into Spotter (Pharo 5 onwards) or with the following load expression: Metacello new smalltalkhubUser: 'TorstenBergmann' project: 'WebBrowser'; configuration: 'WebBrowser'; load # Other If you want to reference it in own configs note that version 0.1.0 is for Pharo 4 while 0.2.0 and following is for Pharo 5 onwards. Bye T.

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Re: [Pharo-users] FFI return by reference
by Thibault Raffaillac April 13, 2016

April 13, 2016

Hi, I tried lots of ways to pass an array, based on the few examples found here and there. My example is: GLES2Buffer class>>gen: n into: buffers self ffiCall: #(void glGenBuffers(int n, int* buffers)) With buffers := FFIExternalArray newType: 'int' size: n (or FFIExternalArray gcExternalNewType: 'int' size: n), the above signature executes without error, but buffers is not updated, so I guess it is copied beforehand. If I replace int* with FFIExternalArray, the values are written correctly in my array. If I replace int* with ByteArray instead I can use any one of ByteArray/IntegerArray/FloatArray ! Only ShortArray, LongArray and DoubleArray are missing then, but they are not crucial right now. So for example: GLES2Buffer class>>create buffer := IntegerArray new: 1. GLES2Buffer gen: 1 into: buffer. ^self new setHandle: (buffer at: 1) :) Same goes for passing coordinates to OpenGL, just with #(-1 -1 -1 1 1 1 1 -1) asFloatArray. Perfect. Cheers, Thibault > Hi, > > Just checked? contrary to what I believed, strings are passed by copy (not by > reference, as ByteArray)? logical for safety but with penalty on > performance... so yes, using a ByteArray is the correct way to do it. (Or an > external value holder, which is a glorified way for passing a ByteArray, but > this probably do not work fine for ?char*" because I didn?t preview it :P) > > Esteban

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Re: [Pharo-users] FFI return by reference
by Thibault Raffaillac April 13, 2016

April 13, 2016

> > 1) Declare a class variable > > > > MyClass class>>initialize > > INT_PTR := FFIExternalValueHolder ofType: ?int?. > > as a larger explanation, this will create an anonymous subclass to keep ?int? > values, than later you can use as a type in your function call. Some people > would call this obscure, but is a good way of solving this problem (I > adopted it from old NB). > If you want to have a named class instead an anonymous class, you can just > subclass FFIExternalValueHolder: > > FFIExternalValueHolder subclass: #MyIntPtr > > and then implement typeDecl class method > > MyIntPtr class>>typeDecl > ^ ?int' > > and this will work as the anonymous class The second option is definitely what I want. I am trying to expose a function returning several ints, as in SDL2>>mouseStateX: y: (excluding the possibility to return a Point). However I would rather not define my own int holder, can't we have generic holders to rely on? Thibault

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Crash when using Athens/Roassal?
by Alexandre Bergel April 13, 2016

April 13, 2016

Hi! In case you are using Athens or Roassal, you may have noticed a loss of stability since we have moved to Spur and the new FFI. I would like to identify the cause of it and I may have an idea. What I would like to ask you, is in case you have experienced this problem, can you send (directly) me the crash.dmp file created next to your image please? Cheers, Alexandre -- _,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;: Alexandre Bergel http://www.bergel.eu ^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;.

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Re: [Pharo-users] [Bug - Pharo 5.0] Remove a class but not remove for RPackage
by Blondeau Vincent April 13, 2016

April 13, 2016

Hello, First, which version of Pharo do you have? (run: Smalltalk lastUpdateString). Second, I cannot reproduce your bug. Can you create a simple and dummy example (with classes A and B for instance) that enlightens the problem? Cheers, Vincent De : Pharo-users [mailto:pharo-users-bounces@lists.pharo.org] De la part de Yann Dubois EnvoyÃ© : mercredi 13 avril 2016 15:02 Ã : Any question about pharo is welcome Objet : [Pharo-users] [Bug - Pharo 5.0] Remove a class but not remove for RPackage Hello, When I delete a class, a window pop to inform me that some methods use this class. So I remove the methods because they are not usefull without my class to removed. But when I close the window, the methods stay on the Browser, so I remove this methods on the Browser. Then, I remove an other class and "BOOM" an error appears, the key which represents my class is not present in the SystemDictionnary (it's normal), but I can find the key in the RPackage metaclasses. !!!************************************************************************************* "Ce message et les piÃ¨ces jointes sont confidentiels et rÃ©servÃ©s Ã l'usage exclusif de ses destinataires. Il peut Ã©galement Ãªtre protÃ©gÃ© par le secret professionnel. Si vous recevez ce message par erreur, merci d'en avertir immÃ©diatement l'expÃ©diteur et de le dÃ©truire. L'intÃ©gritÃ© du message ne pouvant Ãªtre assurÃ©e sur Internet, la responsabilitÃ© de Worldline ne pourra Ãªtre recherchÃ©e quant au contenu de ce message. Bien que les meilleurs efforts soient faits pour maintenir cette transmission exempte de tout virus, l'expÃ©diteur ne donne aucune garantie Ã cet Ã©gard et sa responsabilitÃ© ne saurait Ãªtre recherchÃ©e pour tout dommage rÃ©sultant d'un virus transmis. This e-mail and the documents attached are confidential and intended solely for the addressee; it may also be privileged. If you receive this e-mail in error, please notify the sender immediately and destroy it. As its integrity cannot be secured on the Internet, the Worldline liability cannot be triggered for the message content. Although the sender endeavours to maintain a computer virus-free network, the sender does not warrant that this transmission is virus-free and will not be liable for any damages resulting from any virus transmitted.!!!"

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SQLite bridge crashed Pharo 5.
by Offray Vladimir Luna CÃ¡rdenas April 13, 2016

April 13, 2016

Hi all, I'm working with visualizations a external dataset which contains 270k records. So the best strategy seems to bridge pharo with SQLite to keep requirements low while using Roassal to visualize aggregated information that is obtained from querying the database. That seemed working fine for a while, but just a few minutes ago my image started to crash and after a while it crashed beyond being useful (it doesn't start anymore). I have added the crash dump file, to see if anyone of you can help me making sense of it and trying to detect where is the failure. I imagine that there is something wrong about the way I'm making the query This is the suspect method: ==================== totalOffshoresByCountry "I load the offshores data from a SQLite database or cvs file" | queryResults | self dataLocation exists ifFalse: [ self downloadData ] ifTrue: [ database := (SQLiteConnection fileNamed: dataLocation fullName ) open. queryResults := database executeQuery: 'SELECT country_name, COUNT(*) AS "total_offshores" FROM (SELECT country_name, Description_ FROM nodesNW INNER JOIN node_countriesNW ON nodesNW.Unique_ID = node_countriesNW.NODEID1 ORDER BY country_name) GROUP BY country_name']. ^ queryResults ==================== I have restarted a new image, but I can not remember which package provides SQLiteConnection. I imagine is some migration of NBSQLite under UFFI, but I can not find it in the pharo catalog. Any help with this is welcomed. Cheers, Offray

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Conditional external dependencies in a Metacello BaselineOf?
by Damien Pollet April 13, 2016

April 13, 2016

I have a couple projects that I develop together; the first depending on the second, and both managed on GitHub (in separate repositories). The BaselineOf therefore expresses the dependency using repository: 'github://â¦' However, I'd like to locally change that to gitfiletree:// so that I can build new development images from scratch, with both projects ready to commit to gitfiletree, with minimal repo juggling and code reloading ? Is there a way to achieve that? Metacello project attributes? a git submodule? -- Damien Pollet type less, do more [ | ] http://people.untyped.org/damien.pollet

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Re: [Pharo-users] FFI return by reference
by Thibault Raffaillac April 12, 2016

April 12, 2016

> I will not add for the moment that predefined types value holders? We would > need to add one for each type we support to be consistent, and document it, > and add tests. > And btw? you do have a generic holder? is just that you need to refine it to > what you want :) Couldn't we use FFIInt32? To me it would make sense to use the class to refer to the type, and an instance of it for a value holder in memory (this is not asking for a change, only reporting it looks strange). > My advise is that you go with what you need, we can consider add predefined > value holders later. Yep, I am sticking to the basic features as much as possible anyway. Cheers, Thibault

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New project: AR.Drone communication API in Pharo
by Carolina HernÃ¡ndez April 12, 2016

April 12, 2016

Hi, my name is Carolina Hernandez and I'm a Computer Engineering student at the University of Chile. As part of my final degree project, I'm creating a communication API for controlling the Parrot AR.Drone 2.0 from Pharo. I've just released an early version. The code is hosted in Smalltalkhub: http://smalltalkhub.com/#!/~CaroHernandez/ArDronePharo I also made a video of a test flight, where the AR.Drone is controlled using the API and keyboard: https://www.youtube.com/watch?v=d8rERiBoD0o I couldn't find any direct way to use a joystick in Pharo, if someone knows about one, I'd like to integrate it to my code. Development and tests have been done in Pharo 4.0 and ubuntu 12.04 Comments are welcome! Caro

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