January 2018 - Pharo-users - lists.pharo.org

Re: [Pharo-users] Exception in Gofer with Pharo 7

by Stephane Ducasse

Hi Rafael thanks for reporting. Can you provide a sample that reproduce the error? Stef On Fri, Jan 5, 2018 at 12:41 PM, Rafael Luque <rafael.luque.leiva(a)gmail.com> wrote: > Hi all. > > I'm trying to load some packages from SmalltalkHub and I get an exception > because ByteString did not understand #asUrl. > > Maybe it is related with String>>asUrl deprecated? > https://pharo.fogbugz.com/f/cases/2896/Deprecate-String-asUrl > > Thank you!

Jan. 7, 2018

Re: [Pharo-users] Is there a way to stop arrays sorting automatically?

by Andrew Black

+1 for what Richard says. Moreover, if you know that n is small, and you really want copies of all th permutations, then adding a copy message to your block is really simple. But if the permutationsDo: method made the copy, then it would be useless except for very small values of n. The comment that Richard quotes is in Pharo too. There is a good reason for the current behaviour, and it is documented.

Jan. 7, 2018

Re: [Pharo-users] Grafoscopio (Initial) Feedback

by Paul DeBruicker

Hi Offray, I think the docs you want are here: https://github.com/Metacello/metacello/blob/master/docs/MetacelloUserGuide.… and https://github.com/Metacello/metacello/blob/master/docs/MetacelloScriptingA… Hope this helps, Paul Offray Vladimir Luna CÃ¡rdenas-2 wrote > Hi Sean, > > I would like to use the Metacello script you advised to me for loading > Grafoscopio. The Gopher scripts were created following documentation in > PBE2. > > Does any has pointers to documentation on how to create Metacello > installing scripts? > > Thanks, > > Offray > > > On 31/12/17 11:08, Sean P. DeNigris wrote: >> Offray Vladimir Luna CÃ¡rdenas-2 wrote >>> Now they're in the SThub and also in the PDF Manual linked there. >> Ah, okay I see they are updated for 6.1, but they still use Gofer. Also, >> IIRC (I moved all my development to git a while ago now) the best >> practice >> is to always keep the most up-to-date ConfigurationOf in the canonical >> repo >> (i.e. yours) and then /copy/ it to the relevant platform >> metaRepoForXyz's. >> Otherwise, in my experience one invites chaos because people are >> downloading >> variously out-of-date configs from multiple sources (like me last night >> spending time reporting already-fixed bugs; don't worry I'm not upset!). >> See >> my previous post for the preferred script that should be expected to work >> on >> /any/ supported platform. >> >> >> >> ----- >> Cheers, >> Sean >> -- >> Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html >> >> -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

Jan. 6, 2018

Re: [Pharo-users] Is there a way to stop arrays sorting automatically?

by Richard O'Keefe

I would check this in Pharo, but have so far failed to get it running under Ubuntu 17.10. Squeak _is_ running there, sort of, and the definition of #permutationsDo: in Interval is this code: permutationsDo: aBlock "Repeatly value aBlock with a single copy of the receiver. Reorder the copy so that aBlock is presented all (self size factorial) possible permutations." "(1 to: 4) permutationsDo: [:each | Transcript cr; show: each printString]" self asArray permutationsDo: aBlock Exactly the same comment is found in SequenceableCollections. Are you sure that Pharo has something different? "with a SINGLE COPY of the receiver" is pretty important. The thing is that the number of permutations is so astronomically large that it really never makes sense to retain all of them in memory. Suppose an array of n elements takes n+2 words, then holding all of the permutations of 1..k would take (k+2)*k! + k! + 2 = k!(k+3)+2 words. For k = 5 10 15 20 that's 962 47174402 23538138624002 55956746188062720002 words. If we assume a 64-bit laptop with 16 GiB of memory, k=12 is already too big. Yet it is perfectly reasonable to iterate over all 12! permutations. Another thing about iterating over permutations is that straightforward algorithms take O(1) time per permutation, but not if you copy every time. I don't think I've ever found a use for #permutationsDo: that didn't need to be turned into a specialised backtracking algorithm with cutoffs pushed as early as possible.

Jan. 6, 2018

Re: [Pharo-users] [ANN] Python3Generator and MatplotLibBridge

by Dimitris Chloupis

Ah ok so you want to target the AST specifically, I see now. Yeap I did not implement any security measure for Atlas because the goal was local and not remote execution. Yes indeed the socket connects directly to 127.0.0 port 4000.So Atlas is preconfigured to work locally. I think safety is something that the developer must control to make it specific to the nature of the code. Plus I am no web dev. Plus if OS security is breached to gain access to Atlas, the user is already in a deep mess, Atlas will be the least of his concerns. If my assumption is correct and you execute python code by writing it to a python file and then executing the module, note that this approach is actually much slower to the socket approach. Which is why I did not go for it in the first place. Sockets work similar to files but use memory and thus do not write to hard disk and so they work faster. Which is why sockets are so popular for local IPC as well. I am not sure if Pipes as faster but I doubt it. Memory mapped files are much safer and much faster, which is why shared memory is the most popular IPC for local comunication , the hacker would have to hack the memory low level style because memory mapped files are controlled by the OS kernel and is basically what is used for shared libraries, the very popular DLLs on windows , dylib on MacOS, and so on Linux. If performance becomes a serious issue for you and you want the safest way to do local IPC , I highly recommend this approach. But if you are happy with your current solution, there is no need to modify your code. On Fri, Jan 5, 2018 at 9:09 PM Julien <julien.delplanque(a)inria.fr> wrote: > > Le 5 janv. 2018 Ã 17:15, Dimitris Chloupis <kilon.alios(a)gmail.com> a > Ã©crit : > > > > >> >> Python3Generator allows to generate a Python 3 AST programatically. So >> basically you have objects that represent Python 3 AST nodes and some >> messages in top of that to make the generation of the AST easier from Pharo. >> >> E.g. >> >> ast := 'print' asP3GIdentifier callWith: #('Hello world'). >> >> ast inspect >> > > yes buy why ? Why you want to generate objects , Python AST nodes are > already python objects and you already generate AST nodes each time you > execute python code. > > Using the Atlas syntax your above example would be simpler > > py = ATLPyParser new > > py print:'("Hello World")' > > Is there an advantage using your own syntax ? Is there any advantage of > direct access to Python AST? > > > In MatplotLibBridge I do some checking/optimisations on the AST generated > by high-level API objects (e.g. for optimisation avoid importing a package > twice). > With an AST it is easy with basic Atlas I think this is not possible. > Having an AST allow to do stuff on the code to execute before executing it > and this easily > and maintainable (i.e. not using regexes). > > >> <Capture dâeÌcran 2018-01-05 aÌ 13.06.41.png> >> >> If you have a look at the readme on GitHub you will see more complexe >> examples. >> >> Yes I did take a look but I still did not know why you bother generating > identifiers for each python command manually when ATLPyParser does this > automatically for you. > > For example you have this example > > "Use and initialize the FFI interpreter." > P3GInterpreter useFFIInterpreter. > P3GInterpreter current pathToPython: '/usr/bin/python3'. > > instr := P3GInstructionsList new. > > json := 'json' asP3GIdentifier. > file := 'file' asP3GIdentifier. > os := 'os' asP3GIdentifier. > > instr addAll: { > json import. > os import. > file <- ('open' asP3GIdentifier callWith: #('/tmp/osp3g.json' 'w')). > (file=>#write) callWith: { (json=>#dumps) callWith: {{ > 'os' -> (os=>#name). > 'uname' -> (os=>#uname) call } asDictionary} }. > ((file=>#close) call) > }. > > instr execute. > > > Using the ATLPyParser of Atlas would have been much simpler > > py = ATLPyParser > > Atlas sendMessage:'import json,os' > > py > file:'= open("/tmp/osp3.json","w")';e; > file write:'(json.dump({"os":os.name,"uname":os.uname}))';e; > file close;e. > > Or the point is to fully parse pharo syntax to python ? > > > What I would like to experiment for fun is translating Pharo Smalltalk to > Python 3. > > And as said before with your technique you can not modify the AST easily > before sending it to Python. > > > > >> I wanted that to avoid the user having to set up a Python server >> listening on a socket when it is not needed to get data from Python. >> >> Yep, but if I want to get value from Python into Pharo, I want to have >> them as Pharo objects so as you said some conversion has to be made which >> means more work. >> > > Actually the server is setup at Pharo side, Python side is merely a > client. All the heavy lifting is taking place via Pharo. The user does not > need to do anything , its automatic. But yeah if you want to completely > liberate yourself from sockets I can understand that, though I do not > understand why, you use sockets every time you access the internet and they > are really fast. So its not as if you can avoid socket generation. > > > I agree that sockets are not costly but a problem I see with them is that > it creates a *huge* security issue by letting anyone execute arbitrary > Python code from the outside (except if you configured atlas to only accept > connections from 127.0.0.1). Since I do not need socket to execute > arbitrary code I prefer not using them. > >

Jan. 5, 2018

Re: [Pharo-users] [ANN] Python3Generator and MatplotLibBridge

by Julien

> > Le 5 janv. 2018 Ã 17:15, Dimitris Chloupis <kilon.alios(a)gmail.com> a Ã©crit : > > > > > Python3Generator allows to generate a Python 3 AST programatically. So basically you have objects that represent Python 3 AST nodes and some messages in top of that to make the generation of the AST easier from Pharo. > > E.g. > > ast := 'print' asP3GIdentifier callWith: #('Hello world'). > > ast inspect > > yes buy why ? Why you want to generate objects , Python AST nodes are already python objects and you already generate AST nodes each time you execute python code. > > Using the Atlas syntax your above example would be simpler > > py = ATLPyParser new > > py print:'("Hello World")' > > Is there an advantage using your own syntax ? Is there any advantage of direct access to Python AST? In MatplotLibBridge I do some checking/optimisations on the AST generated by high-level API objects (e.g. for optimisation avoid importing a package twice). With an AST it is easy with basic Atlas I think this is not possible. Having an AST allow to do stuff on the code to execute before executing it and this easily and maintainable (i.e. not using regexes). > > <Capture dâeÌcran 2018-01-05 aÌ 13.06.41.png> > > If you have a look at the readme on GitHub you will see more complexe examples. > > > Yes I did take a look but I still did not know why you bother generating identifiers for each python command manually when ATLPyParser does this automatically for you. > > For example you have this example > > "Use and initialize the FFI interpreter." > P3GInterpreter useFFIInterpreter. > P3GInterpreter current pathToPython: '/usr/bin/python3'. > > instr := P3GInstructionsList new. > > json := 'json' asP3GIdentifier. > file := 'file' asP3GIdentifier. > os := 'os' asP3GIdentifier. > > instr addAll: { > json import. > os import. > file <- ('open' asP3GIdentifier callWith: #('/tmp/osp3g.json' 'w')). > (file=>#write) callWith: { (json=>#dumps) callWith: {{ > 'os' -> (os=>#name). > 'uname' -> (os=>#uname) call } asDictionary} }. > ((file=>#close) call) > }. > > instr execute. > > Using the ATLPyParser of Atlas would have been much simpler > > py = ATLPyParser > > Atlas sendMessage:'import json,os' > > py > file:'= open("/tmp/osp3.json","w")';e; > file write:'(json.dump({"os":os.name <http://os.name/>,"uname":os.uname}))';e; > file close;e. > > Or the point is to fully parse pharo syntax to python ? What I would like to experiment for fun is translating Pharo Smalltalk to Python 3. And as said before with your technique you can not modify the AST easily before sending it to Python. > > > I wanted that to avoid the user having to set up a Python server listening on a socket when it is not needed to get data from Python. > > Yep, but if I want to get value from Python into Pharo, I want to have them as Pharo objects so as you said some conversion has to be made which means more work. > > Actually the server is setup at Pharo side, Python side is merely a client. All the heavy lifting is taking place via Pharo. The user does not need to do anything , its automatic. But yeah if you want to completely liberate yourself from sockets I can understand that, though I do not understand why, you use sockets every time you access the internet and they are really fast. So its not as if you can avoid socket generation. I agree that sockets are not costly but a problem I see with them is that it creates a *huge* security issue by letting anyone execute arbitrary Python code from the outside (except if you configured atlas to only accept connections from 127.0.0.1). Since I do not need socket to execute arbitrary code I prefer not using them.

Jan. 5, 2018

Re: [Pharo-users] [ANN] Python3Generator and MatplotLibBridge

by Dimitris Chloupis

> > Python3Generator allows to generate a Python 3 AST programatically. So > basically you have objects that represent Python 3 AST nodes and some > messages in top of that to make the generation of the AST easier from Pharo. > > E.g. > > ast := 'print' asP3GIdentifier callWith: #('Hello world'). > > ast inspect > yes buy why ? Why you want to generate objects , Python AST nodes are already python objects and you already generate AST nodes each time you execute python code. Using the Atlas syntax your above example would be simpler py = ATLPyParser new py print:'("Hello World")' Is there an advantage using your own syntax ? Is there any advantage of direct access to Python AST? > > [image: Capture dâeÌcran 2018-01-05 aÌ 13.06.41.png] > > If you have a look at the readme on GitHub you will see more complexe > examples. > > Yes I did take a look but I still did not know why you bother generating identifiers for each python command manually when ATLPyParser does this automatically for you. For example you have this example "Use and initialize the FFI interpreter." P3GInterpreter useFFIInterpreter. P3GInterpreter current pathToPython: '/usr/bin/python3'. instr := P3GInstructionsList new. json := 'json' asP3GIdentifier. file := 'file' asP3GIdentifier. os := 'os' asP3GIdentifier. instr addAll: { json import. os import. file <- ('open' asP3GIdentifier callWith: #('/tmp/osp3g.json' 'w')). (file=>#write) callWith: { (json=>#dumps) callWith: {{ 'os' -> (os=>#name). 'uname' -> (os=>#uname) call } asDictionary} }. ((file=>#close) call) }. instr execute. Using the ATLPyParser of Atlas would have been much simpler py = ATLPyParser Atlas sendMessage:'import json,os' py file:'= open("/tmp/osp3.json","w")';e; file write:'(json.dump({"os":os.name,"uname":os.uname}))';e; file close;e. Or the point is to fully parse pharo syntax to python ? > I wanted that to avoid the user having to set up a Python server listening > on a socket when it is not needed to get data from Python. > > Yep, but if I want to get value from Python into Pharo, I want to have > them as Pharo objects so as you said some conversion has to be made which > means more work. > Actually the server is setup at Pharo side, Python side is merely a client. All the heavy lifting is taking place via Pharo. The user does not need to do anything , its automatic. But yeah if you want to completely liberate yourself from sockets I can understand that, though I do not understand why, you use sockets every time you access the internet and they are really fast. So its not as if you can avoid socket generation.

Jan. 5, 2018

Re: [Pharo-users] Grafoscopio (Initial) Feedback

by Offray Vladimir Luna CÃ¡rdenas

Hi Sean, I would like to use the Metacello script you advised to me for loading Grafoscopio. The Gopher scripts were created following documentation in PBE2. Does any has pointers to documentation on how to create Metacello installing scripts? Thanks, Offray On 31/12/17 11:08, Sean P. DeNigris wrote: > Offray Vladimir Luna CÃ¡rdenas-2 wrote >> Now they're in the SThub and also in the PDF Manual linked there. > Ah, okay I see they are updated for 6.1, but they still use Gofer. Also, > IIRC (I moved all my development to git a while ago now) the best practice > is to always keep the most up-to-date ConfigurationOf in the canonical repo > (i.e. yours) and then /copy/ it to the relevant platform metaRepoForXyz's. > Otherwise, in my experience one invites chaos because people are downloading > variously out-of-date configs from multiple sources (like me last night > spending time reporting already-fixed bugs; don't worry I'm not upset!). See > my previous post for the preferred script that should be expected to work on > /any/ supported platform. > > > > ----- > Cheers, > Sean > -- > Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html > >

Jan. 5, 2018

Re: [Pharo-users] Examples of Garage for DB2

by Andrei Stebakov

Thanks, Esteban, it works in my Pharo 6.1. Odbc connection works as well. On Jan 5, 2018 6:28 AM, "Esteban Lorenzano" <estebanlm(a)gmail.com> wrote: this: SmalltalkImage compilerClass: Compiler. Metacello new smalltalkhubUser: 'PharoExtras' project: 'ODBC'; configuration: 'ODBC'; version: #bleedingEdge; load. SmalltalkImage compilerClass: OpalCompiler. loads for me (after proceeding a warning) in Pharo7. no idea if it will work, but it *loads* :) Esteban On 4 Jan 2018, at 18:18, Andrei Stebakov <lispercat(a)gmail.com> wrote: Thank you, Pierce I got similar ffi exceptions when I call Gofer new smalltalkhubUser: 'PharoExtras' project: 'ODBC'; package: 'ConfigurationOfODBC'; load. (Smalltalk at: #ConfigurationOfODBC) load. On Jan 4, 2018 11:41 AM, "Pierce Ng" <pierce(a)samadhiweb.com> wrote: > On Wed, Jan 03, 2018 at 11:42:22AM -0500, Andrei Stebakov wrote: > > I tried before to install odbc.n > > > Gofer new > > squeaksource: 'ODBC'; > > Not Squeaksource. Load the version from Smalltalkhub: > > Gofer new > smalltalkhubUser: 'PharoExtras' project: 'ODBC'; > ... > > Hopefully this version works with or without Esteban's suggestion. > > > I still don't see how postgres can help but I'll give it another try. > > I suggested PostgreSQL FDW because I know PostgreSQL. If you are not > familiar > with PostgreSQL, then setting it up, setting up its FDW, and finally > setting up > programmatic access to PostgreSQL to get at the FDW data is probably more > work > than it is worth. > > Pierce > > >

Jan. 5, 2018

Re: [Pharo-users] [ANN] Python3Generator and MatplotLibBridge

by Julien

> > Le 5 janv. 2018 Ã 12:34, Dimitris Chloupis <kilon.alios(a)gmail.com> a Ã©crit : > > > Well done, great to see my code be reused for new project. I am happy to see people take it one step further. > > What exactly your code offers additional to my code ? Is there is something special you do with it? Python3Generator allows to generate a Python 3 AST programatically. So basically you have objects that represent Python 3 AST nodes and some messages in top of that to make the generation of the AST easier from Pharo. E.g. ast := 'print' asP3GIdentifier callWith: #('Hello world'). ast inspect If you have a look at the readme on GitHub you will see more complexe examples. > > There is a concept of Â« Interpreter Â» in this framework. Basically, an interpreter is an object to which you provide strings containing Python 3 code and that execute it. > > There is a FFI interpreter which writes the python code in a file on the file system and uses the int system(char *) function to make python execute the file. It also redirect stderr to a file and read that file after execution in order to have eventual execution errors. > > You don't really need this approach. The reason why I did not add this feature in Atlas is because the way that Python import its files is basically normal execution. > > So each time you > > import mymodule > > what you do is you execute mymodule. Basically Python does the same thing with execution when it does a import. This is why we need the if main thing to detect whether the module execution happened because of import or because it was executed directly (via terminal, or double click). > > So in case of Atlas all you have to do is put your code in a python module and import then module from atlas with sendMessage: 'import mymoduleâ. I wanted that to avoid the user having to set up a Python server listening on a socket when it is not needed to get data from Python. > > There is a Atlas interpreter which uses the Atlas project from Kilon. Atlas makes Python and Pharo talk trough sockets. So this is what you want I guess. The thing is, if I want to send data from Python Pharo, I would use the Atlas interpreter and serialise data to send to Pharo through a socket as JSON for example. But for Matplotlib I do not need to read Pythonâs value so I did not implemented that. Nevertheless, it could be cool to have this ability to get Pythonâs data in Pharo because we could use Numpy or others Python modules for which getting Python's is important. > > > Atlas provide this ability via getValue: message. There is a catch , what you get is always strings. So that means if you use a complex Python object you will have to convert that to some form of string format that clearly represents the data . JSON could be a good candidate here because both Python and Pharo support this. I have created a very basic template Pharo object that parses strings to Pharo objects as an example that I have included but still its going to be tricky especially with Numpy because it all happens at C level and not Python level for performance reasons. Still its not that hard to do if you really need this feature which in your case you don't. Yep, but if I want to get value from Python into Pharo, I want to have them as Pharo objects so as you said some conversion has to be made which means more work. > Another interesting thing when communicating through sockets between two different languages is: How do you manage callbacks? For example I would like to be able to make Python execute a Pharo Block at a certain point of the execution or to make Pharo execute a Pythonâs lambda. I do not have answer for that. > > > You can do that in Pharo side or Python side , its up to you. Only you need is a string that acts as a single. For example getValue: technically is kinda like a callback because it sends the string containing the python command but it waits for response from Python that will signal it if the return string contains the signature, if I remember correctly, getvalue: value. So essentially what I have done is create a mini transfer protocol. > > It was necessary for me to do this not because of callback per se, but because I wanted to retain the live coding abilities of Pharo while coding using Python libraries. In order to do that I wanted to send Python errors back to Pharo and trigger the Pharo debugger with the python error as the name of the error. To do that I had to implement a protocol that diffirentiate between return values and value that concern only Atlas in this case python errors. > > This protocol can be extended of course to contain a myriad of things, callbacks, thread synchronization, C function calls , C memory etc. > > So technically speaking its already possible through Atlas. If you want to do something very special with callback that involves the Pharo IDE as I did with Python error you only need to extend this protocol adding your own kind of signal strings. > > I think you could re-use the ideas behind the bridge but not the code. It is really specific to Python 3, I do not see how you could generate LISP using it as is. > > Julien > > As far as my Atlas is concerned I had made also a Python 2 version but never bothered to continue developing it because I needed only Python 3. The good news is Python 2 and 3 have minor differences when it comes to sockets. > > Indeed Atlas wont work magically with other language but porting it is not hard because I tried to keep the majority of the code as much as I could in Pharo side for this precise reason. So my initial intention was to provide Atlas to Pharo community as a means to use libraries of any programming language from inside Pharo. I hoped that people would use it as the foundation to bring other languages inside Pharo like I did for Python but alas it seems Pharoers for some weird reason prefer to use Pharo :D (joke for those that did not notice the laughing smiley face) > > I was also planning adding the ability of memory mapped files that I used in my CPPBridge prohect. This form of communication accelerate things by thousands of times because its low level. But it sacrifices remote execution which means in this case you fall back to the existing socket bridge approach. This was necessary at the time because sockets are not a good idea if you plan on doing large loops, because obviously there is a delays , its low around 1 millisecond and less depending on the power of CPU but if you do 1 million iterations would turn that 1 millisecond to 1000 seconds which of course is no fun. > > On the other hand even without memory mapped files you can avoid this by making sure you keep the loop either on python side or pharo side with the condition it does not contain Atlas communication commands that open and close the socket. > >

Jan. 5, 2018