July 2020 - Pharo-users - lists.pharo.org

Re: [Pharo-users] Intermediate-Level Tutorials for Pharo

by tbrunz

So I decided to write an application to solve the Zebra Puzzle, by solving this type of problem in general. In Pharo, of course. I worked out a few basic algorithms for making deductions and inferences, and coded them, along with tests, in Pharo 8. Now I've reached the point of having a working "proof of concept" or prototype. It can't (yet) solve the Zebra Puzzle without some "human assistance", but it does keep track of the solution state as it progresses, it handles the bookkeeping, makes the basic deductions/inferences, and produces reports. And I've used it to quickly solve the Zebra Puzzle. I coded the solution as a separate class/method, with extra rules inserted that I was able to infer by iterating to partial solutions, so that it solves the entire thing. It will interesting to develop the remaining algorithms, and it would be nice to eventually create a nice, interactive user interface for it as well. Since I want to fashion this into an intermediate-level tutorial, I need feedback on what I have so far. I don't want my inexperience to lead to me teaching the wrong techniques, etc. to other developers who are learning Pharo. What I have can no doubt be improved, but I need to hear from the master craftsman in this community what parts are compromised and how (and why) it can be made a better example of "how to program in Pharo" properly. If anyone has the time and is willing to help, the code (complete with class & method comments, test classes/methods, and the Zebra Puzzle example) is here: https://github.com/tbrunz/logic-puzzle and I'm available to answer questions about it, of course. -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

July 28, 2020

Re: [Pharo-users] Intermediate-Level Tutorials for Pharo

by tbrunz

Having solved a number of these problems in my youth, I tried to solve this one "by hand". But with 6 attributes of 5 properties each, the "bookkeeping" task was too difficult to deal with while trying to find a consistent solution. It turns out that it's very easy to make an inconsistent conclusion, and it's also difficult to 'unwind' a mistake (if you can figure out where you made your mistake.) After I failed and restarted the puzzle several times in a row, I thought about one of my mantras: "Let humans do the things that humans are good at, and computers do the things that computers are good at." After all, computers are designed to good at processing large amounts of data without confusion or mistakes (assuming the software developers are competent -- and use good tools).Â So why not a computer program that can solve this puzzle? -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

July 28, 2020

Re: [Pharo-users] Intermediate-Level Tutorials for Pharo

by tbrunz

Recently, I came up with one such project that might work here, and I spent some time prototyping it. The project is to create an application in Pharo that can solve the "Zebra Puzzle". What's the Zebra Puzzle? It's an example of a "constraint satisfaction problem", which are also known as "logic puzzles". This particular puzzle was published inÂ Life International MagazineÂ in 1962 and consists of a set of constraints for allocating a set of values (properties) of attributes in a mutually-exclusive way: 1. There are five houses. 2. The Englishman lives in the red house. 3. The Spaniard owns the dog. 4. Coffee is drunk in the green house. 5. The Ukrainian drinks tea. 6. The green house is immediately to the right of the ivory house. 7. The Old Gold smoker owns snails. 8. Kools are smoked in the yellow house. 9. Milk is drunk in the middle house. 10. The Norwegian lives in the first house. 11. The man who smokes Chesterfields lives in the house next to the man with the fox. 12. Kools are smoked in the house next to the house where the horse is kept. 13. The Lucky Strike smoker drinks orange juice. 14. The Japanese smokes Parliaments. 15. The Norwegian lives next to the blue house. Now, who drinks the water? Who owns the zebra? -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

July 28, 2020

Intermediate-Level Tutorials for Pharo

by tbrunz

tl;dr: I have some ideas about more advanced Pharo tutorials, and I have an example that I would like to have reviewed/critiqued before I develop it any further. I've been thinking lately that it would be nice to expand the number of Pharo tutorials we have available. But rather than (or along with) creating more "beginner" level tutorials, I'd like to see some good "intermediate" level Pharo tutorials. I think that programmers who already know the Pharo syntax and messaging semantics could benefit from more advanced tutorials that demonstrate how to develop "real world" Pharo code for "real world" processing needs. What I'm talking about is something that assumes you know the language, the basics of the IDE (but not necessarily how to leverage its capabilities to aid development), and the basics of the foundation classes (but not its details). I'd like a tutorial for intermediate Pharo programmers who want to become experts with Pharo. Something that can show you how to apply the tools of the IDE and the features of the language and base classes to create solutions that solve complex problems. What does the community think of this idea? -Ted -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

July 28, 2020

Fuel - FLSerializer tests are not working (pharo 8)

by Davide Varvello

Hi Guys, There is something wrong with Fuel. I got the version for Pharo 8 Metacello new repository: 'github://theseion/Fuel:3.0.2/repository'; baseline: 'Fuel'; load. But tests are red, all tests of FLBinaryFileStreamBasicSerializationTest and others Cheers Davide -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

July 27, 2020

Re: [Pharo-users] UFFI asynchronous callbacks

by tesonep＠gmail.com

Hello, for executing it you will need the headless VM. If you are using Pharo Launcher you can change the VM for that image in the configuration combo box (The click on "Edit Configurations..."). If you are using the zero-conf you can use "wget -O - get.pharo.org/64/vmHeadlessLatest90 | bash" Cheers, Pablo On Sat, Jul 25, 2020 at 10:17 AM ASAM <vmax28575(a)gmail.com> wrote: > > Hi Pablo, > today I have a little bit of time to try out the "threaded FFI". > But immediately with the load I get the following error message > "PrimitiveFailed: primitive #primitiveInitializeQueueWith: in > TFCallbackQueue failed". > > see pic: <http://forum.world.st/file/t372350/ThreadedFFI.png> > > When I load it again it looks good. But then I get the error message with > every Pharo start. > > To rule out possible errors, I tested with a fresh Pharo8 64bit image, of > course. > > Could you tell me what i'm doing wrong? > > Thanks > ASAM > > > > > > > > > > > -- > Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html > -- Pablo Tesone. tesonep(a)gmail.com

July 27, 2020

Re: [Pharo-users] UFFI asynchronous callbacks

by ASAM

no code is needed as I mentioned ... .... But immediately with the load Metacello new baseline: 'ThreadedFFI'; repository: 'github://pharo-project/threadedFFI-Plugin'; onConflictUseLoaded; load. To rule out possible errors, I tested with a fresh Pharo8 64bit image, of course. -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

July 25, 2020

Re: [Pharo-users] UFFI asynchronous callbacks

by Ben Coman

Could you provide the actual code you are running? On Sat, 25 Jul 2020 at 16:17, ASAM <vmax28575(a)gmail.com> wrote: > > Hi Pablo, > today I have a little bit of time to try out the "threaded FFI". > But immediately with the load I get the following error message > "PrimitiveFailed: primitive #primitiveInitializeQueueWith: in > TFCallbackQueue failed". > > see pic: <http://forum.world.st/file/t372350/ThreadedFFI.png> > > When I load it again it looks good. But then I get the error message with > every Pharo start. > > To rule out possible errors, I tested with a fresh Pharo8 64bit image, of > course. > > Could you tell me what i'm doing wrong? > > Thanks > ASAM > > > > > > > > > > > -- > Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html >

July 25, 2020

Re: [Pharo-users] UFFI asynchronous callbacks

by ASAM

Hi Pablo, today I have a little bit of time to try out the "threaded FFI". But immediately with the load I get the following error message "PrimitiveFailed: primitive #primitiveInitializeQueueWith: in TFCallbackQueue failed". see pic: <http://forum.world.st/file/t372350/ThreadedFFI.png> When I load it again it looks good. But then I get the error message with every Pharo start. To rule out possible errors, I tested with a fresh Pharo8 64bit image, of course. Could you tell me what i'm doing wrong? Thanks ASAM -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

July 25, 2020

Re: [Pharo-users] How to get text field value and send to bat file

by shawon58

hi as i get idea in my one nameTextInput is the place what receive data. but that data i want to send but how to thats the issue. Thanks -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

July 25, 2020