September 2020 - Pharo-users

Re: [Pharo-users] Can it do this way ?

by Richard O'Keefe

There are two quite different questions. (1) Where may dashes occur in a real ISBN-10? (2) What does Exercism require in the specification and check in the test cases? For (1) the rules are Each ISBN consists of 5 elements with each section being separated by spaces or hyphens. Three of the five elements may be of varying length: - *Prefix element* â currently this can only be either 978 or 979. It is always 3 digits in length - *Registration group element* â this identifies the particular country, geographical region, or language area participating in the ISBN system. This element may be between 1 and 5 digits in length - *Registrant element* - this identifies the particular publisher or imprint. This may be up to 7 digits in length - *Publication element* â this identifies the particular edition and format of a specific title. This may be up to 6 digits in length - *Check digit* â this is always the final single digit that mathematically validates the rest of the number. It is calculated using a Modulus 10 system with alternate weights of 1 and 3. An ISBN-10 does not have the three-digit prefix. So we have [0-9]{1,5} -- prefix [0-9]{1,7} -- registrant [0-9]{1,6} -- publication [0-9X] -- check digit As an examplw, "Standard C++ IOStreams and Locales" by Langer & Kreft has ISBN-10 0-201-18395-1 ISBN-13 9780201183955 so I shall assume the separators are optional. /^[0-9]{1,5}[- ]?[0-9]{1,7}[- ]?[0-9]{1,6}[- ]?[0-9X]$/ Of course the elements cannot all have their maximum length at the same time. In AWK I would write x = a_putative_ISBN_10 y = x gsub(/[- ]+/, "", y) if (x ~ /^[0-9]{1,5}[- ]?[0-9]{1,7}[- ]?[0-9]{1,6}[- ]?[0-9X]$/ \ && y ~ /^[0-9]{9,9}[0-9X]$/ \ ) { x *might* be valid, we still need to check the checksum } For (2), there appear to be no restrictions on where dashes may occur or how many: "These may be communicated with or without hyphens". Exercism doesn't allow spaces. Regular expressions are elegant in their own way, BUT for this problem they are (a) excessive, (b) inefficient, and (c) insufficient. digit count := 0. check sum := 0. for each character c of the string if c is not a hyphen then if c is a digit then digit value := c's value as a digit else if c is X and digit count = 9 then digit value := 10 else return false. digit count := digit count + 1. if digit count > 10 then return false. check sum := (11 - digit count) * digit value + check sum. return check sum mod 11 is zero. Part of the insight here is "don't DO it, just PRETEND you did." That is, instead of copying the string without the hyphens, just ignore the hyphens as they turn up. Another part is "if you are only going to use it once, don't store it." That is, we need a digit's value just once, in the update to check sum, so we should compute it just before we need it, not store it. Now the pseudo-code above is classic sequential imperative coding. Classic functional coding does something like let no_dashes = filter (/= '-') (explode string) in length no_dashes = 10 and let check = last no_dashes in (is_digit check or check = 'X') and all is_digit (take 9 no_dashes) and let xval c = if x = 'X' then 10 else digit_value c in dot (map xval no_dashes) [10,9..1]) mod 11 = 0 This pseudo-code translates nicely to Smalltalk too. You might want to add SequenceableCollection>> with: other inject: initial into: aBlock |r| r := initial. self with: other do: [:x :y | r := aBlock value: r value: x value: y]. ^r dot: other ^self with: other inject: 0 into: [:acc :x :y | x*y + acc] (These methods are so obvious that it would be absurd to claim any intellectual property rights to them.) I also have "fusion" methods like SequenceableCollection>> from: start to: finish allSatisfy: testBlock self from: start to: finish do: [:each | (aBlock value: each) ifFalse: [^false]]. ^true so that ((seq copyFrom: a to: z) allSatisfy: blk) can be done as (seq from: a to: z allSatisfy: blk) without making a copy. Fusion methods are useful because Smalltall compilers don't work as hard at eliminating intermediate data structures as functional language compilers. (Having other priorities.) (isdigit (last no_dashes return false if digit count > 10. On Tue, 8 Sep 2020 at 03:02, Steffen MÃ¤rcker <merkste(a)web.de> wrote: > No problem. I am not knowledgeable about isbn numbers. At which places may > a dash occur? > > Kind regards, > Steffen > > 07.09.2020 16:18:22 Roelof Wobben via Pharo-users < > pharo-users(a)lists.pharo.org>: > > > Op 6-9-2020 om 10:07 schreef Steffen MÃ¤rcker: > >> Maybe this is a naive question, but can you just split the task into the > >> following two? > >> > >> 1. Check whether whether the string is syntactically an ISBN number. > >> This can be done, e.g., using a regex. > >> > >> 2. Check the the check character. > >> Calculate the check character from the (now to be known) syntactically > >> valid string. > >> > >> ISBNValidator>>isValidISBN: aString > >> ^(self isSyntacticallyValid: aString) and: [self isCheckCharacterValid: > >> aString] > >> > >> Kind regards, > >> Steffen nder if the code will not be too big. I learned that it is good > >> > > Sorry to respond not earlier but your respons seems to be in the spam > folder of my provider. > > > > I could do that but if very bad in regex so I do not know a regex which > van validate 123456789 or 123-456-78-9 > > > > Roelof > > > >

Sept. 8, 2020

Re: [Pharo-users] Pharo on a Netbook running TinyCore Linux

by tbrunz

BTW, TinyCore Linux was started by Robert Shingledecker. He's the guy who led the "Damn Small Linux" project[1]; when it dissolved, he started TinyCore and kept going... [1] http://www.damnsmalllinux.org/ -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

Sept. 8, 2020

Re: [Pharo-users] Pharo on a Netbook running TinyCore Linux

by tbrunz

This is running 32-bit Pharo 80 on 32-bit TinyCore 11.1 (Linux kernel 5.4.3). There is a 64-bit version of TinyCore, which I plan to test next... Then test 64-bit Pharo 80 and try Pharo Launcher on top of that. Then on a Raspberry Pi... Here's what's intriguing about this: TinyCore Linux is SUPER tiny -- 11MB for the headless 'Core' version, and 16MB for a FLTK/FLWM desktop. (Many different desktops are available.) The 'CorePlus' version (which I'm booted on) is still only 106MB; it supports Wifi & comes with installation tools & a variety of DEs to pick from. With TinyCore, you "build it the way you like it", by adding just the packages you want in your Linux image. With a stripped-down implementation, it's around the same size as the Pharo VM! Which makes TinyCore basically "a snap-on HAL module for the Pharo VM" that gives you what amounts to bare-metal operation -- and it can run 100% from RAM (as well as via mounting packages from persistent storage, on a package-by-package basis). You can persist TinyCore on disk, and keep your installed packages ("tce extensions") and your settings & user files persisted separately. That helps keep the TinyCore OS from being corrupted -- it's much like the '.image' file for Pharo; your changes are kept in a separate file. This opens up the possibility of making tiny/embedded little "appliances" that boot into TC, then auto-launch a Pharo image -- headless or with a UI, all without the burden of launching/maintaining full OS to do so. -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

Sept. 8, 2020

Re: [Pharo-users] Pharo on a Netbook running TinyCore Linux

by tbrunz

Just to be sure I'm not booted into Ubuntu: <http://forum.world.st/file/t372161/Pharo8-32_TinyCore_AcerD255_2020-0907b.j…> -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

Sept. 8, 2020

Pharo on a Netbook running TinyCore Linux

by tbrunz

This is cool... After I booted TinyCore Linux[1] on my 10-year-old netbook[2], I decided to see if it could run Pharo... It does! Details: [1] http://tinycorelinux.net/ - TinyCore Linux "CorePlus", 32-bit, version 11.1. - Booted from a YUMI multiboot thumbdrive. - Installed 'curl', 'bash', Firefox (to access 'pharo.org' site for download info). [2] https://www.notebookcheck.net/Review-Acer-Aspire-One-D255-Netbook-N550.4015… - Acer D255 "AspireONE" netbook (Sept, 2010). - 2 GB RAM (single DIMM). - 250 GB SSD (not being used; TinyCore running 100% in RAM). The Proof: <http://forum.world.st/file/t372161/Pharo8-32_TinyCore_AcerD255_2020-0907.jpg> -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

Sept. 8, 2020

[Ann] Workshop (3rd session) IndieWeb with pocket infrastructures

by Offray Vladimir Luna CÃ¡rdenas

Hi, This is a short annoucement about our workshops related IndieWeb with pocket infrastructures. Our third session would be this Saturday 12 Sept, from 15:15 to 19:15 (GMT-5). You can find more information in [1] and the documentation in [2]. Following a "local first" approach, the documention and workshops will be happening in Spanish but the interactive notebooks and code will be written in English [3][3a][4][5]. [1] https://is.gd/dataroda50 [2] https://mutabit.com/repos.fossil/indieweb/ [3] https://mutabit.com/repos.fossil/brea/ [3a] https://code.tupale.co/Offray/Brea [4] https://code.tupale.co/Offray/Grafoscopio [5] https://code.tupale.co/Offray/GrafoscopioUtils Cheers, Offray

Sept. 7, 2020

Re: [Pharo-users] Can it do this way ?

by Steffen MÃ¤rcker

Now having a Workspace at hand, I fixed some minor typos: IsbnVarifier>>isSyntacticIsbn: aString | nonGrouped dashes spaces grouped | nonGrouped := '\d{9}[0-9X]' asRegex. "groups separated by either dashes or spaces" dashes := '\d{1,7}-\d{1,7}-\d{1,7}-[0-9X]'. spaces := '\d{1,7} \d{1,7} \d{1,7} [0-9X]'. grouped := (dashes , '|' , spaces) asRegex. ^(aString matchesRegex: nonGrouped) or: [(aString matchesRegex: grouped) and: [aString size = (10 + 3)]] Best, Steffen Am .09.2020, 19:01 Uhr, schrieb Steffen MÃ¤rcker <merkste(a)web.de>: > Hi, > > after reading the link and some additional sources, it turns out that a > valid ISBN-10 has either no separators or four blocks separated by either > dashes or spaces: > Group-Publisher-Title-CheckDigit > > Assuming Regex11 (and that I made no mistake), the following should do > the > trick: > > IsbnVarifier>>isSyntacticIsbn: aString > "no groups" > noGrouped := '\d{9}[0-9X]' asRegex. > "groups separated by either dashes or spaces" > dashes := '\d{1,7}-\d{1,7}-\d{1,7}-[0-9X]' > spaces := '\d{1,7} \d{1,7} \d{1,7} [0-9X]' > grouped := (dashed , '|' , spaces) asRegex. > > ^(aString matches: nonGrouped) or: > [(aString matches: grouped) and: > [aString size = 10 + 3]] > > Surely, you could cleverly compress the regex even further but that does > not matter for this example. After checking the syntax, you can just > iterate over the string and compute the check-digit on the fly. > > Kind regards, > Steffen > > Am .09.2020, 18:19 Uhr, schrieb Roelof Wobben via Pharo-users > <pharo-users(a)lists.pharo.org>: > >> See here for all the tests : >> https://github.com/exercism/pharo-smalltalk/blob/master/exercises/isbn-veri… >> >> Roelof >> >> >>

Sept. 7, 2020

Re: [Pharo-users] Can it do this way ?

by Steffen MÃ¤rcker

Hi, after reading the link and some additional sources, it turns out that a valid ISBN-10 has either no separators or four blocks separated by either dashes or spaces: Group-Publisher-Title-CheckDigit Assuming Regex11 (and that I made no mistake), the following should do the trick: IsbnVarifier>>isSyntacticIsbn: aString "no groups" noGrouped := '\d{9}[0-9X]' asRegex. "groups separated by either dashes or spaces" dashes := '\d{1,7}-\d{1,7}-\d{1,7}-[0-9X]' spaces := '\d{1,7} \d{1,7} \d{1,7} [0-9X]' grouped := (dashed , '|' , spaces) asRegex. ^(aString matches: nonGrouped) or: [(aString matches: grouped) and: [aString size = 10 + 3]] Surely, you could cleverly compress the regex even further but that does not matter for this example. After checking the syntax, you can just iterate over the string and compute the check-digit on the fly. Kind regards, Steffen Am .09.2020, 18:19 Uhr, schrieb Roelof Wobben via Pharo-users <pharo-users(a)lists.pharo.org>: > See here for all the tests : > https://github.com/exercism/pharo-smalltalk/blob/master/exercises/isbn-veri… > > Roelof > > >

Sept. 7, 2020

Re: [Pharo-users] Getting rid of .sources file for deployment

by Esteban Maringolo

Hi Stef, I don't know what's the demand for such a feature. In the Windows and Desktop era it might have been very important, but I don't see that kind of integration these days, when most system integrations happen at the HTTP level. For my particular case I don't need a DLL. Regards! Esteban A. Maringolo On Mon, Sep 7, 2020 at 1:55 PM StÃ©phane Ducasse <stephane.ducasse(a)inria.fr> wrote: > > I would like also to be able to deploy a pharo app as a dll juts time and money. > > S. > > On 7 Sep 2020, at 17:28, Esteban Maringolo <emaringolo(a)gmail.com> wrote: > > Hi Davide, > > Thanks for the thorough response, but I think you're over > dimensioning, and to some extent missing, my initial purpose and > intention. > > I don't want to protect from somebody attempting to reverse engineer > my application, that's impossible (more so given your references). > I simply want to disable the option to open the IDE, even with all > tool menus disabled. > > In Java if I deliver a .jar or .war anybody could reverse engineer it, > but launching it won't open the development environment. > > For comparison with other Smalltalks I've used: > * VisualWorks enables the distribution of a "headless" IMAGE (and > parcels) without sources, if you revert that image to be headful all > source code will be decompiled using meaningless variables. > * Dolphin has the concept of SessionManager that is the entry point to > the image startup, if you save your image with a Headless Session > manager, then no GUI loop will start, same thing if you deploy as a > COM component. > * VAST produces its own ICX file where you can choose what to include > in it, it's not simply saving the image but building a new one from > within the development image, it's one step further. > * VSE had the SLL (similar to DLLs), if you don't bind the IDE's SLLs > then there is no way to start the IDE (I never built a headless VSE > app though). > > So what I'd like is an always Pharo headless image or Pharo headless > vm, instead of being controlled by a parameter in the VM. > > Regards, > > Esteban A. Maringolo > > On Mon, Sep 7, 2020 at 12:04 PM Davide Grandi <davide.grandi(a)email.it> wrote: > > > Ok, I'll give you a result, meanwhile fixing some imprecisions. > > The "class" is CogVmSimulator but it's use is very far from my knowlegde, > I recalled having seen a picture of Pharo-in-Pharo (or Squeak-in-Squeak) > running under this simulator. > It lives near the Cog side (or the OpenVM side) of Squeak/Pharo > (If I'm not wrong Squeak ran into an emulator, before walking on his > legs-his VM). > > There are many of these simulator, for other Smalltalk : > - Hobbes and others for Xerox (thanks to files of Mario Molczko and/or > Bitsavers > - Dan Ingalls Apda Smalltalk + old Smalltalk -72 /-76 > and maybe others I don't yet know about > > The reason is quite simple : the object memory is written to disk > and the spec of executing Smalltalk are known either from the books > or by the source. > > The root is Xerox's SystemTracer, a class that wrote a running image > to disk, optionally changing object format (see the Green Book). > > So : > - if you can read the image > - you can run into a simulator > - or decode it without to much effort (5 emulators for Xerox V2 image, > so far). > (try to open an image with a text editor : intriguing !) > > I don't know how Cincom or Instantiations protect the released st code, > but for Pharo and Squeak this is not a point : they are all open. > > So, as if you wanna "protect" names and methods of a running image ... > ... you have to (IMHO) : > - encrypt executable and image (and modify the VM) > - or obfuscate your classes and methods renaming it to > C1, C2, ..., m1:p1:p2: and so on (keeping a map for debugging) > > Sorry to be imprecise about names and locations > apart from suggest to see 4 emulators 4 running in a squeak image > running ... in javascript in your browser (so total is 5) at : > https://smalltalkzoo.thechm.org/HOPL-Squeak.html?earlyst80 > (thanks to Vanessa Freudemberg & Dan Ingalls). > > Sorry again & best regards, > > Davide Grandi > > On 06/09/2020 23:51, Esteban Maringolo wrote: > > If somebody gets to open the image and loads it with an Smalltalk > Emulator to execute it I'll ask him/her to start working together, and > even teach me how to do it. > > I don't want to shield the image from being accessed, just want to > make it harder than simply removing the '--headless' parameter to the > VM executable. > Of course removing sources is a plus (I do for a VW deployed image), > but even for this particular piece of software that I'm asking for, I > don't need it. > > If I wanted to make the source public, I'll publish it in > Github/Gitlab, otherwise I'd rather keep the code private. > > Regards, > > Esteban A. Maringolo > > On Sun, Sep 6, 2020 at 6:29 PM Davide Grandi <davide.grandi(a)email.it> wrote: > > I mean that with SmalltalkEmulator, the Smalltalk interpreter > written in Smalltalk, one can execute an image looking at > classes, methods and maybe executing code at will. > > And the only practical form of protection I see in Squeak/Pharo > is to obfuscate code. > > Maybe I'm wrong. > > Davide Grandi > > On 06/09/2020 22:27, Esteban Maringolo wrote: > > On Sun, Sep 6, 2020 at 12:52 PM Davide Grandi <davide.grandi(a)email.it> wrote: > > Does "competition" has SmalltalkEmulator ? > A Smalltalk-written VM will defeat any simple obfuscation scheme. > > Sorry, but I don't understand what you mean. > > Best regards, > > -- > Ing. Davide Grandi > email : davide.grandi(a)email.it > mobile : +39 339 7468 778 > linkedin : http://linkedin.com/in/davidegrandi > > > -- > Ing. Davide Grandi > email : davide.grandi(a)email.it > mobile : +39 339 7468 778 > linkedin : http://linkedin.com/in/davidegrandi > > > > > -------------------------------------------- > StÃ©phane Ducasse > http://stephane.ducasse.free.fr / http://www.pharo.org > 03 59 35 87 52 > Assistant: Aurore Dalle > FAX 03 59 57 78 50 > TEL 03 59 35 86 16 > S. Ducasse - Inria > 40, avenue Halley, > Parc Scientifique de la Haute Borne, BÃ¢t.A, Park Plaza > Villeneuve d'Ascq 59650 > France >

Sept. 7, 2020

Re: [Pharo-users] Getting rid of .sources file for deployment

by StÃ©phane Ducasse

I would like also to be able to deploy a pharo app as a dll juts time and money. S. > On 7 Sep 2020, at 17:28, Esteban Maringolo <emaringolo(a)gmail.com> wrote: > > Hi Davide, > > Thanks for the thorough response, but I think you're over > dimensioning, and to some extent missing, my initial purpose and > intention. > > I don't want to protect from somebody attempting to reverse engineer > my application, that's impossible (more so given your references). > I simply want to disable the option to open the IDE, even with all > tool menus disabled. > > In Java if I deliver a .jar or .war anybody could reverse engineer it, > but launching it won't open the development environment. > > For comparison with other Smalltalks I've used: > * VisualWorks enables the distribution of a "headless" IMAGE (and > parcels) without sources, if you revert that image to be headful all > source code will be decompiled using meaningless variables. > * Dolphin has the concept of SessionManager that is the entry point to > the image startup, if you save your image with a Headless Session > manager, then no GUI loop will start, same thing if you deploy as a > COM component. > * VAST produces its own ICX file where you can choose what to include > in it, it's not simply saving the image but building a new one from > within the development image, it's one step further. > * VSE had the SLL (similar to DLLs), if you don't bind the IDE's SLLs > then there is no way to start the IDE (I never built a headless VSE > app though). > > So what I'd like is an always Pharo headless image or Pharo headless > vm, instead of being controlled by a parameter in the VM. > > Regards, > > Esteban A. Maringolo > > On Mon, Sep 7, 2020 at 12:04 PM Davide Grandi <davide.grandi(a)email.it> wrote: >> >> Ok, I'll give you a result, meanwhile fixing some imprecisions. >> >> The "class" is CogVmSimulator but it's use is very far from my knowlegde, >> I recalled having seen a picture of Pharo-in-Pharo (or Squeak-in-Squeak) >> running under this simulator. >> It lives near the Cog side (or the OpenVM side) of Squeak/Pharo >> (If I'm not wrong Squeak ran into an emulator, before walking on his >> legs-his VM). >> >> There are many of these simulator, for other Smalltalk : >> - Hobbes and others for Xerox (thanks to files of Mario Molczko and/or >> Bitsavers >> - Dan Ingalls Apda Smalltalk + old Smalltalk -72 /-76 >> and maybe others I don't yet know about >> >> The reason is quite simple : the object memory is written to disk >> and the spec of executing Smalltalk are known either from the books >> or by the source. >> >> The root is Xerox's SystemTracer, a class that wrote a running image >> to disk, optionally changing object format (see the Green Book). >> >> So : >> - if you can read the image >> - you can run into a simulator >> - or decode it without to much effort (5 emulators for Xerox V2 image, >> so far). >> (try to open an image with a text editor : intriguing !) >> >> I don't know how Cincom or Instantiations protect the released st code, >> but for Pharo and Squeak this is not a point : they are all open. >> >> So, as if you wanna "protect" names and methods of a running image ... >> ... you have to (IMHO) : >> - encrypt executable and image (and modify the VM) >> - or obfuscate your classes and methods renaming it to >> C1, C2, ..., m1:p1:p2: and so on (keeping a map for debugging) >> >> Sorry to be imprecise about names and locations >> apart from suggest to see 4 emulators 4 running in a squeak image >> running ... in javascript in your browser (so total is 5) at : >> https://smalltalkzoo.thechm.org/HOPL-Squeak.html?earlyst80 >> (thanks to Vanessa Freudemberg & Dan Ingalls). >> >> Sorry again & best regards, >> >> Davide Grandi >> >> On 06/09/2020 23:51, Esteban Maringolo wrote: >>> If somebody gets to open the image and loads it with an Smalltalk >>> Emulator to execute it I'll ask him/her to start working together, and >>> even teach me how to do it. >>> >>> I don't want to shield the image from being accessed, just want to >>> make it harder than simply removing the '--headless' parameter to the >>> VM executable. >>> Of course removing sources is a plus (I do for a VW deployed image), >>> but even for this particular piece of software that I'm asking for, I >>> don't need it. >>> >>> If I wanted to make the source public, I'll publish it in >>> Github/Gitlab, otherwise I'd rather keep the code private. >>> >>> Regards, >>> >>> Esteban A. Maringolo >>> >>> On Sun, Sep 6, 2020 at 6:29 PM Davide Grandi <davide.grandi(a)email.it> wrote: >>>> I mean that with SmalltalkEmulator, the Smalltalk interpreter >>>> written in Smalltalk, one can execute an image looking at >>>> classes, methods and maybe executing code at will. >>>> >>>> And the only practical form of protection I see in Squeak/Pharo >>>> is to obfuscate code. >>>> >>>> Maybe I'm wrong. >>>> >>>> Davide Grandi >>>> >>>> On 06/09/2020 22:27, Esteban Maringolo wrote: >>>>> On Sun, Sep 6, 2020 at 12:52 PM Davide Grandi <davide.grandi(a)email.it> wrote: >>>>>> Does "competition" has SmalltalkEmulator ? >>>>>> A Smalltalk-written VM will defeat any simple obfuscation scheme. >>>>> Sorry, but I don't understand what you mean. >>>>> >>>>> Best regards, >>>> -- >>>> Ing. Davide Grandi >>>> email : davide.grandi(a)email.it >>>> mobile : +39 339 7468 778 >>>> linkedin : http://linkedin.com/in/davidegrandi >> >> -- >> Ing. Davide Grandi >> email : davide.grandi(a)email.it >> mobile : +39 339 7468 778 >> linkedin : http://linkedin.com/in/davidegrandi >> >> > -------------------------------------------- StÃ©phane Ducasse http://stephane.ducasse.free.fr / http://www.pharo.org 03 59 35 87 52 Assistant: Aurore Dalle FAX 03 59 57 78 50 TEL 03 59 35 86 16 S. Ducasse - Inria 40, avenue Halley, Parc Scientifique de la Haute Borne, BÃ¢t.A, Park Plaza Villeneuve d'Ascq 59650 France

Sept. 7, 2020