February 2016 - Pharo-users

Pharo mooc registration is available
by stepharo Feb. 4, 2016

Feb. 4, 2016

https://www.france-universite-numerique-mooc.fr/courses/inria/41010/session…

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stupid spur question
by Werner Kassens Feb. 4, 2016

Feb. 4, 2016

Hi, in the developersforum i read: "And in 32-bits there are only BoxedFloat64 instances. So on a 32 bits VM Floats are represented only by BoxedFloat64. On a 64 bits VM Floats are represented either by BoxedFloat64 or SmallFloat64. " i wonder whether this means, that in 32 bit systems there exist images that dont have the SmallFloat64 object. i mean, if i make a package with a method for SmallFloat64, this would not trigger an exception on a 32 bit systems if i load it on such a system, or would it? werner

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Another question about Spec
by Julien Delplanque Feb. 4, 2016

Feb. 4, 2016

Hey, I use drag and drop between two lists in a project and I read this tutorial [1] to learn how to do it. My question is: Is there a way to have another object than a String as passengers in #acceptDropBlock: (I get passengers the same way as in the tutorial i.e sending #passenger to transfer object) like the objects really in the list? Because if I use #displayBlock: it became difficult to be sure I retrieve the object I dropped in the source list... Thanks in advance, Julien [1]: http://spec.st/docs/drag_n_drop/

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Re: [Pharo-users] Scrollbar in Spec layout
by LE Xuan Sang Feb. 4, 2016

Feb. 4, 2016

Hello, Here goes an example snapshot of my problem. Cheer, Sang > Date: Wed, 3 Feb 2016 16:59:01 +0800 > From: Ben Coman <btc(a)openinworld.com> > To: Any question about pharo is welcome <pharo-users(a)lists.pharo.org> > Subject: Re: [Pharo-users] Scrollbar in Spec layout > Message-ID: > <CAProBTmEm_aYDpoCFrptCQgA3Xx7MmDO67W5bMghSC50q69Hyw(a)mail.gmail.com> > Content-Type: text/plain; charset=UTF-8 > > On Wed, Feb 3, 2016 at 4:45 PM, LE Xuan Sang <xsang.le(a)gmail.com> wrote: >> Hello, >> >> I use Spec (Pharo 4) to develop my GUI application. In my Spec layout, one of the columns has a large amount of rows (dynamic content indeed). So i need it to be scrollable. Does anyone knows how to add a scrollbar to that column? >> >> Thanks, >> >> LE Sang > > I'm not sure if I'm the one to help you, but could you post a snapshot? > cheers -ben > >

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XML verification using an external XSD file - possible yet in Pharo?
by PAUL DEBRUICKER Feb. 4, 2016

Feb. 4, 2016

Hi - Is there a way to validate XML files with an external XML schema file (XSD file) in Pharo ? Something like xerces (http://xerces.apache.org/) or xmllint (http://xmlsoft.org/xmllint.html) provide? Thanks Paul

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Create type(class) dynamically
by Khrystyna Mykhailiuk Feb. 3, 2016

Feb. 3, 2016

Hi, all! Is it possible in Pharo to create a type (class) dynamically? Not using special space for it, but create type by running method of another class. Thanks, Khrystyna. -- View this message in context: http://forum.world.st/Create-type-class-dynamically-tp4875651.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

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an example of debugging with moldable tools
by Tudor Girba Feb. 3, 2016

Feb. 3, 2016

Hi, One thing we noticed over the past year since we introduced GT in Pharo is that people still tend to use these tools in a similar way classic tools were used. We think there is a more potential in these tools. To change this, we would like to collect stories of how using these tools enabled a workflow that was otherwise not possible. To get this started, we will start to document more consistently some of the sessions, and we would like to get input from your as well. The idea is to create a catalog of tutorials that people can follow and get inspired from. Let me start. I recently had to debug a small problem, and I ended up having an experience that I found beautiful: http://www.humane-assessment.com/blog/debugging-duplicated-behavior-with-gt… What do you think? Cheers, Doru -- www.tudorgirba.com www.feenk.com "Don't give to get. Just give."

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Pharo and OpenMP
by Dimitris Chloupis Feb. 3, 2016

Feb. 3, 2016

First my apology for the very long post but I think this will interest a lot of people. I have seen that someone out there .... HELOOOOOOO.... has tried Pharo with OpenMP https://pharoweekly.wordpress.com/2015/07/17/pharo-and-openmp/ For those that dont know what the hell OpenMP is, it nothing more than a collection of C pragmas, not very diffirent to our pharo pragmas , that tell to a compiler how to make code parallel. By parallel I don't mean pharo threads which are not really code that executes at the same time but true hardware threads and taking advantage of multiple cores etc. A pharo holy grail. Parallel coding is a bitch, there a lot of logical problems to face when you have pieces of code executing at the same time and you have to be aware of how the hardware is doing it because if you dont it so easy to get code as slow as running it on a single thread. I have been watching youtube tutorials by one of the guys that made OpenMP and I have to say I am very impressed. And it got me wondering "why the hell not pharo". The nice thing about OpenMP is that it does not matter that pharo VM can do only 1 thread which is the main thread, you can do multiple threads at C side using OpenMP and then collapse them to one thread and send the result back to pharo. Also note OpenMP is engineered by Intel so its a very serious library and comes included with most modern compilers and that includes GCC. Visual Studio and Clang / LLVM On the other hand lately I am also researching shared memory, actually its shared memory that lead me to OpenMP. My idea is basically extending the live coding enviroment of pharo beyond pharo. Its sound a bit crazy but the way I see it from my very small knowledge of C and shared memory is that right now, pharo live coding evniroment is isolated from outside world. You can do live coding while inside pharo but the moment you go outside , say you call a C library , live coding goes out of the window. This why we need to have session management to manage resource of calling C libraries to make sure when we reload the image , the image does not freak out that the live state of the C libraries is gone. This is also why many people push things to the image side. And of course its much more fun to code in Pharo than C. Now bare with me because things are now getting really interesting.... what if we could have an image flle for C code ? The things is that I am interested into shared memory because I want a very fast IPC, shared memory is the faster. I want to communicate Pharo with Blender, that I have accomplished via sockets, I can call python code and python libraries from pharo. But sockets are expensive in large loops, they work great for simple communication and much faster than pipes when used locally but try a large loop and socket will lag. Shared memory on the other hand is super fast, it basically it gives a part of memory that is shared among process that means also different applications. Now how a C image file fits into all this you may ask. Its simple. The most popular way of shared memory is called "memory mapped file", what it does is that it takes a file and loads it to memory as it is... sound familiar ? ;) what however is also doing is that it allows you share that part of the memory with any other application/ process as long as it also tries to load the file mapped to memory the same way. So what that means that we can have a place in memory that is shared between C code, including C dlls, and Pharo code. That file can act as an image file because we take that shared memory at any time that has been modified either by pharo, C or whatever else has access to shared memmory and store it back to that file. This is functionality that memory mapped files provide called msync. We talk here about a C image that work at least on surface very similarly to Pharo image. Now where OpenMP fits in all this ? Since OpenMP is about code that eats processors like peanuts , yes we could call it from a DLL, but with my approach even if that code crashes we will be able to restore it back to its live state because of that image format. All we do is reopen the memory mapped file and restore from it the shared memory. So we end up with true parallel live C/Pharo code with live state that and of course live code that is shared between Pharo and pretty much anything that uses C or python or why not other languages. So far I know how to do all of the above, well at least I am learning it now. Now the real challenge, which I have no clue about, is to make a Pharo parser to C using OpenMP. My thinking is as following. Why code in C and OpenMP when you could take something like Slang, which is basically pharo code that compiles to C, use pharo code with some pharo pragmas corresponding to OpenMP pragmas that will allow you to compile Slang OpenMP to C OpenMP and then compile it to an executable or dll that uses the shared memory memory mapped file solution. Crazy ? realistic ? far fetched ? maybe ? good in theory back in practice? Open to your thoughts.

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Scrollbar in Spec layout
by LE Xuan Sang Feb. 3, 2016

Feb. 3, 2016

Hello, I use Spec (Pharo 4) to develop my GUI application. In my Spec layout, one of the columns has a large amount of rows (dynamic content indeed). So i need it to be scrollable. Does anyone knows how to add a scrollbar to that column? Thanks, LE Sang

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Smalltalkhub is down?
by Julien Delplanque Feb. 2, 2016

Feb. 2, 2016

Hey, I can not access smalltalkhub neither from an image nor from a web browser. Also, if I ping the server it does not responds. Anyone experiencing the same thing? Julien

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