- Pharo-users - lists.pharo.org

New to Pharo. "Could not coerce arguments" (Problem with character encoding?) + Learning resources?
by M O Oct. 19, 2019

Oct. 19, 2019

Hi, I'm new to Pharo, and generally, in programming. I decided that my first programming language is going to be Pharo. However I have encountered some issues when I was exploring some examples. I don't want them to bother me later, so I'd like them to be resolved as soon as possible. Some info: OS: Windows 8.1, language Polish, Pharo version: 7 stable 64, Pharo Launcher installed in C:\PharoLauncher, images and VMs located in C:\users\<user>\Documents\... My Windows account (admin user) username contains non-ASCII character ("Å"). I tested all cases below on account with only ASCII characters ("Administrator") and they all work just fine. Therefore I strongly suspect the main source of issues is character encoding but I have no idea how to solve it or if it's actual problem. Noticed that #1 and #2 fails when attempting to perfom FFI call Here's the list of things with issues I encountered: 1. AthensDemoMorph example (Args-1 and Args-2) 2. Downloading packages from git repository (Git-1 and Git-2) In second example it goes straight to downloading from git repo, while first throws error 1. Pharo Mooc (Mooc) Instead of "Å" there are displayed some "rubbish" characters I opened debugger in case #1 and #2 (On personal account) and noticed that variable "ec" (error code I guess) has value 29 (See "invokeWithArgs") in method "invokeWithArguments", and variable "errCode" has value 6 (See "externalCallFailed") in method "externalCallFailed". I guess those values are related to Windows error codes so I looked them up on Microsoft site. For 6 I found it's error "ERROR_INVALID_HANDLE", while for 29 it's "ERROR_WRITE_FAULT". As I mentioned above, this might be character encoding problem, but this is just my guessing. Hope you can help me resolve it. Second thing I'd like to ask is, what are best up to date learning resources for Pharo? I'm mainly concerned about tools. I know a bit about idea of "real" OOP (from Alan Kay's talks). Is Mooc (http://mooc.pharo.org/) and Pharo by Example 5 enough for start? For Mooc, do I need to use Mooc image (It uses a bit outdated Pharo version) or can I use simply Pharo 7?

2 1

Re: [Pharo-users] Glorp + P3 + SQLite
by Todd Blanchard Oct. 19, 2019

Oct. 19, 2019

I should probably mention that I do not really have a great handle on how package configurations work these days. Coming back to Smalltalk after a long time away. Pointer to an explanation of how package configurations work would be great.

1 0

Re: [Pharo-users] Glorp + P3 + SQLite
by Sven Van Caekenberghe Oct. 19, 2019

Oct. 19, 2019

Hi Todd, Both specify their dependency on Glorp almost the same way: P3: spec baseline: 'Glorp' with: [ spec repository: 'github://pharo-rdbms/glorp:master/']. Sqlite3: spec baseline: 'Glorp' with: [ spec repository: 'github://pharo-rdbms/glorp' ]. What exactly is the conflict ? Sven > On 19 Oct 2019, at 10:26, Todd Blanchard via Pharo-users <pharo-users(a)lists.pharo.org> wrote: > > > From: Todd Blanchard <tblanchard(a)mac.com> > Subject: Glorp + P3 + SQLite > Date: 19 October 2019 at 10:26:10 GMT+2 > To: Any question about pharo is welcome <pharo-users(a)lists.pharo.org> > > > I loaded GLORP+P3 without issue. > > Trying to load SQLite3 - it also wants to load GLORP which complains of conflict. > > For P3 I used: > > Metacello new > > > baseline: 'P3' > ; > > repository: 'github://svenvc/P3' > ; > > load: 'glorp'. > > > For SQLite: > > Metacello new > > > repository: 'github://PierceNg/glorp-sqlite3:pharo7' > ; > > baseline: 'GlorpSQLite' > ; > load. > > > but this fails with a conflict. I suspect the conflict is it wants to load in glorp again. > > I would also like to have mysql driver at some point. > > Any tips for getting these to play nice together would be great. > >

2 1

Glorp + P3 + SQLite
by Todd Blanchard Oct. 19, 2019

Oct. 19, 2019

I loaded GLORP+P3 without issue. Trying to load SQLite3 - it also wants to load GLORP which complains of conflict. For P3 I used: Metacello new baseline: 'P3'; repository: 'github://svenvc/P3'; load: 'glorp'. For SQLite: Metacello new repository: 'github://PierceNg/glorp-sqlite3:pharo7'; baseline: 'GlorpSQLite'; load. but this fails with a conflict. I suspect the conflict is it wants to load in glorp again. I would also like to have mysql driver at some point. Any tips for getting these to play nice together would be great.

1 0

VW -> Pharo
by eftomi Oct. 19, 2019

Oct. 19, 2019

Hi, What is currently the most efficient way to import a parcel / code from VW 8.3 to Pharo 7 or 8? Thanks and best wishes, Tomaz -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

2 2

Smallest docker image for pharo >=7 ?
by HernÃ¡n Morales Durand Oct. 18, 2019

Oct. 18, 2019

Hi guys, Because I am lazy and want to avoid searching through all DockerHub repository pages... Do you know a Dockerfile to generate the smallest possible docker image for Pharo? I am also interested in which stage you use to install packages into the image, and why? Do you copy the contained image into docker already built? or do you prefer install packages on building? (as done by pip -r requirements.txt) Anyone using xpra binding from subuser [1]? Anyone could make it work Pharo on Alpine since it uses different libc? Anyway sharing opinions would be also appreciated. [1] http://subuser.org/news/0.3.html Cheers. HernÃ¡n

6 11

[ANN] Next Pharo Sprint: Oct 25
by Marcus Denker Oct. 18, 2019

Oct. 18, 2019

We will organize a Pharo sprint / Moose dojo Oct 25, starting at 10:00am. (Local Time Paris). Goals of this sprint: - Pharo 8: Fix issues from tracker https://github.com/pharo-project/pharo/issues <https://github.com/pharo-project/pharo/issues> Remote Sprint: Remotely, you can join us on Discord. During the sprint, we synchronize local and remote Pharo sprinters: http://pharo.org/contribute-events <http://pharo.org/contribute-events> We have added a Board to coordinate the work: https://github.com/orgs/pharo-project/projects/9 <https://github.com/orgs/pharo-project/projects/9> Known Local Sprint meetings - Lille/France: It will be at the Inria Lille, Building B, third floor (RMoD offices). As the building is not open to the public, please contact us before if you plan to come A list of all Pharo Event of the year an be found here: https://association.pharo.org/events <https://association.pharo.org/events>

1 0

NVARCHAR and Glorp
by eftomi Oct. 17, 2019

Oct. 17, 2019

Dear all, I'm working on ADO database driver for Glorp by using Pablo's PharoCOM. The structure of the driver is similar to Sven's P3DatabaseDriver and P3Client (thanks, Sven for very clear architecture :-) ) and the work is progressing quite nicely. I can connect to SQL Server, PostgreSQL and create tables, insert and read data directly with ADO Connection and Recordset objects, and with Glorp, too. In next days I'll do some more testing, including Oracle, and publish the prototype on GitHub. The goal is not PostgreSQL, of course, but to finally reach SQL Server, Oracle and possibly MS Access, at least from Windows systems. One thing is bothering me though - SQL Server supports Unicode with NCHAR and NVARCHAR types, and when using INSERT INTO with literal strings these should be prefixed with N, like in N'This is a Unicode string' Does somebody remember whether Glorp can prefix the strings in that way when constructing SQL statements? I checked all the constants and string conversions under DatabasePlatform but haven't found anything related to this kind of prefixing. Thanks and best wishes, Tomaz -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

3 4

Re: [Pharo-users] help with understanding the visitor pattern
by Richard O'Keefe Oct. 17, 2019

Oct. 17, 2019

First, this is presumably the "Die" exercise from the Pharo track of exercism.io. Second, this is a case where - there is nothing to a Die other than the number of faces, so from a practical point of view there should not be a Die class; - there is nothing to a DieHandle other than a sequence of dice, so from a practical point of view there should not be a DieHandle class (not least because the word "Handle" here makes no sense in English and since it may contain many dice it would be better as DiceHandle, if only Handle made sense here). Once you realise that a Die is just an Integer wearing a burqa and a DIeHandle is just an OrderedCollection or Bag wearing a burqa, it may be easier to figure out how to combine these things. Of course it is most unwise to use #+ for combining dice and/or DieHandles. Both because + is a confusing choice and because we already *have* a selector that means "concatenate these two sequences", namely #, Looking at my own answer to this, and others, I see that you want two operations: aDieHandle addDie: aDie aDieHandle + anotherDieHandle You are not required to define + with either operation a Die. One way to do this is to add a new method DieHandle >> addAllTo: another [ dice do: [:each | another addDie: each]. ^another ] then DieHandle >> + another [ ^another addAllTo: (self addAllTo: DieHandle new)) ] Now if you want to extend this to treat a single Die as if it were a DieHandle containing itself, just do Die >> addAllTo: another [ another addDie: self. ^another ] Die >> + another [ ^another addAllTo: (self addAllTo: DieHandle new)) ] Now that Die and DieHandle have some selectors in common (and an actual method), it might make sense to introduce a common superclass. DiceSet (no data) roll ^self roll: Random default roll: rng diceNumber addAllTo: + another ^another addAllTo: (self addAllTo: DieHandle new) Die < DiceSet (faces) roll: rng ^faces atRandom: rng diceNumber ^1 addAllTo: aHandle aHandle addDie: self. ^aHandle DieHandle < DiceSet (dice) roll: rng ^self detectSum: [:die | did roll: rng] diceNumber ^dice size addAllTo: aHandle dice do: [:die | aHandle addDie: die]. ^aHandle What we have here is pretty close to the Composite pattern, not the Visitor pattern. If a DieHandle could accept DieHandles as elements as well as Die instances, it would be a bona fide example of Composite, and the code would need a few minor changes. The Visitor pattern is a way of dealing with "the Expression Problem". You don't *have* that problem. It doesn't seem like a good idea to apply it here. On Wed, 16 Oct 2019 at 21:33, Roelof Wobben via Pharo-users <pharo-users(a)lists.pharo.org> wrote: > > Hello, > > Im busy with this project: https://github.com/RoelofWobben/Die > > Now I also want to try to add a DieHandler and a Die together. > And I heared you can use the visitor pattern to solve this. > > As far as I understand the pattern I have to make a new class which > contains only the + method. > > But I fail to understand to see how I can make a difference between the > + of a Die and the + of a DieHandler. > > So can someone help me understand this pattern and maybe learn me step > by step how to implement this in my code. > > Regards, > > Roelof > >

1 0

Concurrency Best Practices + Tests
by Noury Bouraqadi Oct. 16, 2019

Oct. 16, 2019

Hi everyone, Can I get your input on the following questions : - What are your best practices and recommendations for developing and testing concurrent software? - How to discover need for synchronization/critical sections/ when doing TDD? - How to write code to avoid dead-locks? Noury

8 8