- Pharo-users - lists.pharo.org

[ANN] Willow v14.3.0 [v14.3.0] released!

by Buenos Aires Smalltalk

April 25, 2022

Re: ESUG 2022 call for presentations & Call for student volunteers

by StÃ©phane Ducasse

Hi The deadline for sending presentation proposal is set to 1st of June! So please do not wait the last moment to send your proposals. S > On 13 Jan 2022, at 13:25, stephane ducasse <stephane.ducasse(a)inria.fr> wrote: > > ESUG 2022 > Novisad Serbia 22. â 26.8. > https://esug.github.io/2022-Conference/call2022.html <https://esug.github.io/2022-Conference/call2022.html> > > You can support the ESUG conference in many different ways: > Sponsor the conference. New sponsoring packages are described at http://www.esug.org/supportesug/becomeasponsor/ <http://www.esug.org/supportesug/becomeasponsor/> > Submit a talk, a software or a paper to one of the events. See below. > Attend the conference. We'd like to beat the previous record of attendance (170 people at Amsterdam 2008)! > Students can get free registration and hosting if they enroll into the the Student Volunteers program. See below. > <>Developers Forum: International Smalltalk Developers Conference > > We are looking for YOUR experience on using Smalltalk. You will have 30 min for presentations and 45 min for hands-on tutorials. > The list of topics for the normal talks and tutorials includes, but is not limited to the following: > XP practices, Development tools, Experience reports > Model driven development, Web development, Team management > Meta-Modeling, Security, New libraries & frameworks > Educational material, Embedded systems and robotics > SOA and Web services, Interaction with other programming languages > <>Teaching Pearls and Show us Your Business > > New this year!!! We added two types of sessions in addition to the regular talks and show us your projects sessions. > Show your business 10 min session (Get prepared!!) > Teaching pearls : we want some session on how to teach some design aspects. We want your tip and tricks to teach Smalltalk or OOP. > We expect to have several 10 to 15 min sessions aggregated. > <>How to submit? > > Make a Pull Request here https://github.com/ESUG/esug.github.io/tree/source/2022-Conference/talks <https://github.com/ESUG/esug.github.io/tree/source/2022-Conference/talks> > > Or but only if you are not connected to the worldâ¦ send an email to stephane.ducasse(a)inria.fr <mailto:stephane.ducasse@inria.fr> > > Title: [ESUG 2022] Please follow the template below the email will be automatically processed! > Name: > Email: > Abstract: > Bio: > > Call for Student Volunteers > Student volunteers help keep the conference running smoothly; in return, they have free accommodations, while still having most of the time to enjoy the conference. > > Pay attention: the places are limited so do not wait till the last minute to apply. > > Conference details: > Send an email to stephane.ducasse at inria.fr <http://inria.fr/> and serge.stinckwich at gmail.com <http://gmail.com/> with: > > title: [ESUG 2022 Student] > name, gender, university/school, country, email address > short description of you and why you are interested in participating > For which period is accommodation covered? Accommodation is covered from Sunday 21 August until Friday 26 August 2022 (including nights from Sunday to Monday and from Thursday to Friday). Students will be hosted in student rooms. ESUG additionally covers for the lunches during the week and one dinner. > > Duties include handling registration as people arrive at the conference, filling coffee machines, collecting presentation slides for ESUG right after the presentation is given, being present at an information desk to answer questions, and generally being helpful. Student volunteering makes the conference better, takes a fairly small amount of time and doesn't significantly interfere with enjoying and learning from the conference. Please Note, this role requires discipline and constant attention to all attendees. > > Information about hotel > Student Volunteer rooms are booked at (to be announced). If you are student volunteer, do not book yourself, we have arranged the booking already! >

April 23, 2022

Re: Loading from a git repository with Metacello on a running seaside image

by Esteban Lorenzano

Hi Emilio, You need something like this: Metacello new repository: 'github://pharo-spec/Spec:Pharo10'; baseline: 'Spec2'; onConflict: [ :e | e useIncoming ]; onUpgrade: [ :e | e useIncoming ]; ignoreImage; load ignoreImage, onConflict, onUpgrade. BUT if your image already has a baseline for your project then Metacello will not reload it (hence your project may not be loaded correctly, since baseline may have changed). In that case, I always execute before something like: #( 'BaselineOfSpec2' 'BaselineOfSpecCore' ) do: [ :each | (RPackageOrganizer default packageNamed: each ifAbsent: [ nil ]) ifNotNil: [ :aPackage | aPackage removeFromSystem ] ] I ack this is hacky, but it works :) Esteban On Apr 23 2022, at 3:21 am, Emilio Oca <emiliooca(a)gmail.com> wrote: > Hi List > > I need some help with Metacello, and may be git too > > I would like to be able to, in a running headless image, load the last commit of a git repo > > Something like > Metacello new baseline:'MyProject'; > repository: 'github://myUser/MyProject:main/myProject'; > > load. > works just once and may open some dialogs > > > Something like this > [ > > [ > Metacello new baseline:'MyProject'; > repository: 'github://myUser/MyProject:main/myProject'; > onConflictUseIncoming; > load. > ] on: MetacelloSkipDirtyPackageLoad do: [ :ex | ex resume: false ]. > ] on: MCMergeOrLoadWarning do: [ :ex | ex load ]. > > > Avoids the dialogs and alerts but the code is still not updated. > > My intention is to be able to 'refresh' a running seaside image with its latest development version from a git repo (avoiding to personally reach the server and rebuild the docker image) > What am I missing? > > Best > > Emilio

April 23, 2022

Loading from a git repository with Metacello on a running seaside image

by Emilio Oca

Hi List I need some help with Metacello, and may be git too I would like to be able to, in a running headless image, load the last commit of a git repo Something like Metacello new baseline:'MyProject'; repository: 'github://myUser/MyProject:main/myProject'; load. works just once and may open some dialogs Something like this [ [ Metacello new baseline:'MyProject'; repository: 'github://myUser/MyProject:main/myProject'; onConflictUseIncoming; load. ] on: MetacelloSkipDirtyPackageLoad do: [ :ex | ex resume: false ]. ] on: MCMergeOrLoadWarning do: [ :ex | ex load ]. Avoids the dialogs and alerts but the code is still not updated. My intention is to be able to 'refresh' a running seaside image with its latest development version from a git repo (avoiding to personally reach the server and rebuild the docker image) What am I missing? Best Emilio

April 23, 2022

Re: A question about #beginsWith: and #endsWith:

by Richard O'Keefe

Dan Ingalls is of course a big NAME in the world of Smalltalk, but the stated reason for changing the behaviour of #beginsWith: and #endsWith: makes no sense. We have many ways to define a partial order on strings. x <= y iff y beginsWith: x x <= y iff y endsWith: x x <= y iff y includesSubCollection: x x <= y iff y includesSubSequence: x These things are supposed to obey laws: if a beginsWith: b , c then a beginsWith: b if a endsWith: b , c then a endsWith: c if a includesSubCollection: b , c then a includesSubCollection: b and a includesSubCollection: c if a includesSubSequence: b , c then a includesSubSequence: b and a includesSubSequence: c. We also expect the usual rules of equality to hold. So (1) a beginsWith: a (2) a = '' , a (3) THEREFORE a beginsWith: '' (1) a endsWith: a (2) a = a , '' (3) THEREFORE a endsWith: '' (1) a includesSubCollection: a (2) a = '' , a (3) THEREFORE a includesSubCollect: '' Reasoning about strings (as values) gets enormously more complicated if the operations do not follow simple sensible rules, and having '' be the least string under these orderings and having '' be a prefix and a suffix of any string is essential if the rules are going to be simple and coherent. '' is to strings (and more generally empty sequences are to sequences) pretty much what 0 is to integers. Denying that 'abc' beginsWith: '' is *structurally* just like denying that 0 <= 123. Now as it happens I *can* see a use for versions of #beginsWith: and #endsWith: that diverge from the ones we have, but *this* is not where they need to diverge. a beginsWithGraphemesOf: b iff a asGraphemes = b asGraphemes , c asGraphemes for some c, where s asGraphemes returns a sequence of strings each of which is a maximally long grapheme cluster, such that concatenating s asGraphemes recovers s. That is, #beginsWithGraphemesOf: and #endsWithGraphemesOf: would respect the Unicode Text Segmentation boundaries. But s beginsWithGraphemesOf: '' would still need to be true. The thing is, in practice you often DON'T KNOW whether a potential affix is empty or not. Here are some of my test cases. testTestData "Ensure that the sample string has no duplicates." [(Set withAll: string) size = stringSize] assert. testBeginsWith "Test that every prefix of the sample IS a prefix of it." 0 to: stringSize do: [:n | [string beginsWith: (string copyFrom: 1 to: n)] assert]. testEndsWith "Test that every suffix of the sample IS a suffix of it." 0 to: stringSize do: [:n | [string endsWith: (string copyFrom: stringSize - n + 1 to: stringSize)] assert]. testIndexOfSubCollectionAtBeginning "Test that every prefix of 'abcd' is found at the beginning." 0 to: stringSize do: [:n | |s i t| s := string copyFrom: 1 to: n. i := string indexOfSubCollection: s startingAt: 1. [1 = i] assert. t := string copyFrom: i to: i - 1 + n. [t = s] assert]. testIndexOfSubCollectionAtEnd "Test that every proper suffix of the sample is found at the end." 1 to: stringSize do: [:n | |s i t| s := string copyFrom: stringSize - n + 1 to: stringSize. i := string indexOfSubCollection: s startingAt: 1. [stringSize + 1 - n = i] assert. t := string copyFrom: i to: i - 1 + n. [t = s] assert]. testLastIndexOfSubCollectionAtBeginning "Test that every proper prefix of the sample is found at the beginning." 1 to: stringSize do: [:n | |s i t| s := string copyFrom: 1 to: n. i := string lastIndexOfSubCollection: s startingAt: stringSize. [1 = i] assert. t := string copyFrom: i to: i - 1 + n. [t = s] assert]. testLastIndexOfSubCollectionAtEnd "Test that every suffix of the sample is found at the end." 0 to: stringSize do: [:n | |s i t| s := string copyFrom: stringSize - n + 1 to: stringSize. i := string lastIndexOfSubCollection: s startingAt: stringSize. [stringSize + 1 - n = i] assert. t := string copyFrom: i to: i - 1 + n. [t = s] assert]. testOccurrencesOfEmptyCollection "Test that the empty string occurs at the beginning, at the end, and in between every pair of adjacent characters." [(string occurrencesOfSubCollection: '') = (stringSize + 1)] assert. testOccurrencesOfUniqueParts "Test that unique parts occur as many times as they should." |repeated| repeated := string , string , string. 1 to: stringSize do: [:start | start to: stringSize do: [:finish | |s n| s := string copyFrom: start to: finish. n := string occurrencesOfSubCollection: s. [n = 1] assert. n := repeated occurrencesOfSubCollection: s. [n = 3] assert]]. On Fri, 22 Apr 2022 at 13:57, David T. Lewis <lewis(a)mail.msen.com> wrote: > Hi Richard, > > (CC squeak-dev list, replies to the relevant list please) > > On Thu, Apr 21, 2022 at 12:07:32AM +1200, Richard O'Keefe wrote: > > I've just tracked down a nasty little problem > > porting some code to Pharo. As a result, I > > have added to the comments in my own versions > > of these methods. beginsWith: aSequence > > "Answer true if aSequence is a prefix of the receiver. > > This makes sense for all sequences. > > There is a compatibility issue concerning 'abc' beginsWith: '' > > + VisualWorks, Dolphin, astc, GNU ST (where the method is > > called #startsWith:) and VisualAge (where the method > > is called #wbBeginsWith:) > > agree than EVERY sequence begins with an empty prefix. > > - Squeak and Pharo > > agree that NO sequence begins with an empty sequence. > > # ST/X chooses compatibility with Squeak, heaving a big unhappy > > sigh, and adds #startsWith: to have something sensible to use. > > Now ST/X *thinks* it is compatible with VW, though it isn't, so > > I wonder if this was a bug that VW fixed and Squeak didn't? > > astc goes with the majority here. This is also compatible with > > Haskell, ML, and with StartsWith in C# and startsWith in Java." > > ^self beginsWith: aSequence ignoringCase: false > > > > endsWith: aSequence > > "Answer true if aSequence is a suffix of the receiver. > > This makes sense for all sequences. > > There is a compatibility issue concerning 'abc' endsWith: ''. > > + VisualWorks, Dolphin, astc, GNU ST, and VisualAge (where > > the method is called #wbEndsWith:) > > agree that EVERY sequence ends with an empty suffix. > > - Squeak and Pharo > > agree that NO sequence ends with an empty suffix. > > # ST/X chooses compatibility with the majority, apparently > > unaware that this makes #beginsWith: and #endsWith: > inconsistent. > > astc goes with the majority here. This is also compatible with > > Haskell, ML, C#, and Java." > > ^self endsWith: aSequence ignoringCase: false > > > > Does anyone have any idea > > - why Squeak and Pharo are the odd ones out? > > - why anyone thought making #beginsWith: and #endsWith:, um, "quirky" > > was a good idea (it's pretty standard in books on the theory of > > strings to define "x is a prefix of y iff there is a z such that > > y = x concatenated with z") > > The Squeak behavior was introduced in November 1998 by Dan Ingalls > in conjunction with some VM improvements that he was doing, and was > included in the Squeak2.2 release at that time. > > Prior to that update, Squeak did this: > 'abc' beginsWith: '' ==> true > 'abc' endsWith: '' ==> true > > For Squeak2.2 and later it is: > 'abc' beginsWith: '' ==> false > 'abc' endsWith: '' ==> false > > Pharo presumably inherits this from Squeak. > > I am attaching Dan's original change set from the early Squeak > update stream so you can see the context. > > The change set comment says that "endsWith:, beginsWith:, and match > have been rewritten to take advantage of this considerably faster method" > (referring to a new primitive that Dan had added to the VM in this > change set). > > > > > I was about to try to file a bug report for the first time, > > then realised that maybe other people don't think this IS a bug. > > I don't think it is a bug. I can't think of a case where it makes > sense to say that a string of characters "begins with" or "ends with" > a string that contains nothing. > > In any case, that's the history of the change in Squeak and Pharo as > best as I can reconstruct it. > > HTH, > Dave > >

April 23, 2022

Re: A question about #beginsWith: and #endsWith:

by David T. Lewis

Hi Richard, (CC squeak-dev list, replies to the relevant list please) On Thu, Apr 21, 2022 at 12:07:32AM +1200, Richard O'Keefe wrote: > I've just tracked down a nasty little problem > porting some code to Pharo. As a result, I > have added to the comments in my own versions > of these methods. beginsWith: aSequence > "Answer true if aSequence is a prefix of the receiver. > This makes sense for all sequences. > There is a compatibility issue concerning 'abc' beginsWith: '' > + VisualWorks, Dolphin, astc, GNU ST (where the method is > called #startsWith:) and VisualAge (where the method > is called #wbBeginsWith:) > agree than EVERY sequence begins with an empty prefix. > - Squeak and Pharo > agree that NO sequence begins with an empty sequence. > # ST/X chooses compatibility with Squeak, heaving a big unhappy > sigh, and adds #startsWith: to have something sensible to use. > Now ST/X *thinks* it is compatible with VW, though it isn't, so > I wonder if this was a bug that VW fixed and Squeak didn't? > astc goes with the majority here. This is also compatible with > Haskell, ML, and with StartsWith in C# and startsWith in Java." > ^self beginsWith: aSequence ignoringCase: false > > endsWith: aSequence > "Answer true if aSequence is a suffix of the receiver. > This makes sense for all sequences. > There is a compatibility issue concerning 'abc' endsWith: ''. > + VisualWorks, Dolphin, astc, GNU ST, and VisualAge (where > the method is called #wbEndsWith:) > agree that EVERY sequence ends with an empty suffix. > - Squeak and Pharo > agree that NO sequence ends with an empty suffix. > # ST/X chooses compatibility with the majority, apparently > unaware that this makes #beginsWith: and #endsWith: inconsistent. > astc goes with the majority here. This is also compatible with > Haskell, ML, C#, and Java." > ^self endsWith: aSequence ignoringCase: false > > Does anyone have any idea > - why Squeak and Pharo are the odd ones out? > - why anyone thought making #beginsWith: and #endsWith:, um, "quirky" > was a good idea (it's pretty standard in books on the theory of > strings to define "x is a prefix of y iff there is a z such that > y = x concatenated with z") The Squeak behavior was introduced in November 1998 by Dan Ingalls in conjunction with some VM improvements that he was doing, and was included in the Squeak2.2 release at that time. Prior to that update, Squeak did this: 'abc' beginsWith: '' ==> true 'abc' endsWith: '' ==> true For Squeak2.2 and later it is: 'abc' beginsWith: '' ==> false 'abc' endsWith: '' ==> false Pharo presumably inherits this from Squeak. I am attaching Dan's original change set from the early Squeak update stream so you can see the context. The change set comment says that "endsWith:, beginsWith:, and match have been rewritten to take advantage of this considerably faster method" (referring to a new primitive that Dan had added to the VM in this change set). > > I was about to try to file a bug report for the first time, > then realised that maybe other people don't think this IS a bug. I don't think it is a bug. I can't think of a case where it makes sense to say that a string of characters "begins with" or "ends with" a string that contains nothing. In any case, that's the history of the change in Squeak and Pharo as best as I can reconstruct it. HTH, Dave

April 22, 2022

[ANN] Stargate v8.1.1 [v8.1.1] released!

by Buenos Aires Smalltalk

April 21, 2022

UK Smalltalk User Group Meeting - Wednesday, April 27th

by Giovanni Corriga

The next meeting of the UK Smalltalk User Group will be held on Wednesday, April 27th 2022. Newspeak ( https://bracha.org/Site/Newspeak.html ) is a programming system in the Smalltalk tradition, whose current incarnation runs in the web browser. Newspeak is designed to provide the liveness Smalltalkers expect, as well as features atypical of Smalltalk such as modularity, security and good interoperability with the surrounding ecosystem. In this talk, we'll explain how and why Newspeak differs from Smalltalk and demonstrate the Newspeak IDE. Gilad Bracha is the creator of the Newspeak programming language and a well known researcher in the area of object-oriented programming languages. He was awarded the senior Dahl-Nygaard prize in 2017. He is currently a Technical Fellow at F5, and has held positions at Google, SAP Labs, Cadence, and Sun. He has authored or co-authored several books including the Java Language and Virtual Machine Specifications, and the Dart Programming Language. Prior to joining Sun, he worked on Strongtalk, the Animorphic Smalltalk System. He received his B.Sc in Mathematics and Computer Science from Ben Gurion University in Israel and a Ph.D. in Computer Science from the University of Utah. This will be an online meeting from home. If you'd like to join us, please sign up in advance on the meeting's Meetup page ( https://www.meetup.com/UKSTUG/events/cbklbrydcgbkc/ ) to receive the meeting details. Donât forget to bring your laptop and drinks!

April 20, 2022

Re: A question about #beginsWith: and #endsWith:

by Sven Van Caekenberghe

Since 'abc' includesSubstring: ''. "true" 'abc' indexOfSubCollection: ''. "0" and following basic principles, my first reaction would also be that 'abc' beginsWith: ''. 'abc' endsWith: ''. should both be true. On the other hand, this is really a degenerate case. You know the answer upfront (it does not depend on the actual receiver) and thus it does not tell you much. I vote for this to be a bug. > On 20 Apr 2022, at 14:07, Richard O'Keefe <raoknz(a)gmail.com> wrote: > > I've just tracked down a nasty little problem > porting some code to Pharo. As a result, I > have added to the comments in my own versions > of these methods. beginsWith: aSequence > "Answer true if aSequence is a prefix of the receiver. > This makes sense for all sequences. > There is a compatibility issue concerning 'abc' beginsWith: '' > + VisualWorks, Dolphin, astc, GNU ST (where the method is > called #startsWith:) and VisualAge (where the method > is called #wbBeginsWith:) > agree than EVERY sequence begins with an empty prefix. > - Squeak and Pharo > agree that NO sequence begins with an empty sequence. > # ST/X chooses compatibility with Squeak, heaving a big unhappy > sigh, and adds #startsWith: to have something sensible to use. > Now ST/X *thinks* it is compatible with VW, though it isn't, so > I wonder if this was a bug that VW fixed and Squeak didn't? > astc goes with the majority here. This is also compatible with > Haskell, ML, and with StartsWith in C# and startsWith in Java." > ^self beginsWith: aSequence ignoringCase: false > > endsWith: aSequence > "Answer true if aSequence is a suffix of the receiver. > This makes sense for all sequences. > There is a compatibility issue concerning 'abc' endsWith: ''. > + VisualWorks, Dolphin, astc, GNU ST, and VisualAge (where > the method is called #wbEndsWith:) > agree that EVERY sequence ends with an empty suffix. > - Squeak and Pharo > agree that NO sequence ends with an empty suffix. > # ST/X chooses compatibility with the majority, apparently > unaware that this makes #beginsWith: and #endsWith: inconsistent. > astc goes with the majority here. This is also compatible with > Haskell, ML, C#, and Java." > ^self endsWith: aSequence ignoringCase: false > > Does anyone have any idea > - why Squeak and Pharo are the odd ones out? > - why anyone thought making #beginsWith: and #endsWith:, um, "quirky" > was a good idea (it's pretty standard in books on the theory of > strings to define "x is a prefix of y iff there is a z such that > y = x concatenated with z") > > I was about to try to file a bug report for the first time, > then realised that maybe other people don't think this IS a bug. > > >

April 20, 2022

Re: A question about #beginsWith: and #endsWith:

by Kasper Osterbye

Yes, that one I have come across several times - even without trying to port anything, merely because it is how beginsWith: should work (supporting the empty string). I have no idea about the rationale though. Best, Kasper > On 20 Apr 2022, at 14.07, Richard O'Keefe <raoknz(a)gmail.com> wrote: > > I've just tracked down a nasty little problem > porting some code to Pharo. As a result, I > have added to the comments in my own versions > of these methods. beginsWith: aSequence > "Answer true if aSequence is a prefix of the receiver. > This makes sense for all sequences. > There is a compatibility issue concerning 'abc' beginsWith: '' > + VisualWorks, Dolphin, astc, GNU ST (where the method is > called #startsWith:) and VisualAge (where the method > is called #wbBeginsWith:) > agree than EVERY sequence begins with an empty prefix. > - Squeak and Pharo > agree that NO sequence begins with an empty sequence. > # ST/X chooses compatibility with Squeak, heaving a big unhappy > sigh, and adds #startsWith: to have something sensible to use. > Now ST/X *thinks* it is compatible with VW, though it isn't, so > I wonder if this was a bug that VW fixed and Squeak didn't? > astc goes with the majority here. This is also compatible with > Haskell, ML, and with StartsWith in C# and startsWith in Java." > ^self beginsWith: aSequence ignoringCase: false > > endsWith: aSequence > "Answer true if aSequence is a suffix of the receiver. > This makes sense for all sequences. > There is a compatibility issue concerning 'abc' endsWith: ''. > + VisualWorks, Dolphin, astc, GNU ST, and VisualAge (where > the method is called #wbEndsWith:) > agree that EVERY sequence ends with an empty suffix. > - Squeak and Pharo > agree that NO sequence ends with an empty suffix. > # ST/X chooses compatibility with the majority, apparently > unaware that this makes #beginsWith: and #endsWith: inconsistent. > astc goes with the majority here. This is also compatible with > Haskell, ML, C#, and Java." > ^self endsWith: aSequence ignoringCase: false > > Does anyone have any idea > - why Squeak and Pharo are the odd ones out? > - why anyone thought making #beginsWith: and #endsWith:, um, "quirky" > was a good idea (it's pretty standard in books on the theory of > strings to define "x is a prefix of y iff there is a z such that > y = x concatenated with z") > > I was about to try to file a bug report for the first time, > then realised that maybe other people don't think this IS a bug. > > >

April 20, 2022