January 2016 - Pharo-dev - lists.pharo.org

Code reviews

by Ben Coman

On Thu, Jan 14, 2016 at 12:22 AM, David Allouche <david(a)allouche.net> wrote: > > By the way, how do you guys do code reviews for code integrated into the > core? Its fairly informal. Once a Slice has been submitted to the Pharo5Inbox the associated Issue on Fogbugz is <Resolved> to "Fix review Needed" - people review it out and comment. Unfortunately with limited resources, sometime resolved issues can languish if reviewer don't feel its within their expertise, and often it falls the to small group of the core-devs from Inria. As Pharo grows more popular we may need some improved processes to reduce load on core-devs. I'd be interested in what you've seen work in other environments. Have you seen these... http://pharo.org/contribute-propose-fix https://pharo.fogbugz.com/?W68 cheers -ben

Jan. 13, 2016

Re: [Pharo-dev] GitFileTree and Metacello load from github problem

by Thierry Goubier

Hi Mariano, yes, this is https://pharo.fogbugz.com/f/cases/17125/Metadata-less-compatibility-with-Fi…. It was integrated in Pharo5 (50470) then reverted at one point, so it's no more in the image. I'm trying to reactivate it, but I don't understand what the CI error is. It's the necessary support for FileTree to handle a filetree without metadata format. Thierry Le 13/01/2016 18:13, Mariano Martinez Peck a Ã©crit : > Hi... I am totally dumb today or what?? > > I am trying to load: > > Metacello new baseline: 'OSSubprocess'; repository: > 'github://marianopeck/OSSubprocess:master/repository'; load. > > And I am getting this error: > > However, I am getting this error: > > File Not Found: > > 'File @ > /Users/mariano/Trabajo/PharoConsortium/imagenes/github-cache/marianopeck/OSSubprocess/master/marianopeck-OSSubprocess-18ae52f/repository/OSSubprocess-Tests.package/monticello.meta/version' > > And doing a ls i get: > > ls -la > /Users/mariano/Trabajo/PharoConsortium/imagenes/github-cache/marianopeck/OSSubprocess/master/marianopeck-OSSubprocess-18ae52f/repository/OSSubprocess-Tests.package/monticello.meta/ > > -rw-r--r-- 1 mariano staff 55 Jan 13 14:03 categories.st > <http://categories.st> -rw-r--r-- 1 mariano staff 0 Jan 13 14:03 > initializers.st <http://initializers.st> -rw-r--r-- 1 mariano staff > 27 Jan 13 14:03 package > > > There is no 'version' file as this guy is trying to load. > > The package was saved using GitFileTree. > > Thanks in advacne > > -- Mariano http://marianopeck.wordpress.com

Jan. 13, 2016

GitFileTree and Metacello load from github problem

by Mariano Martinez Peck

Hi... I am totally dumb today or what?? I am trying to load: Metacello new baseline: 'OSSubprocess'; repository: 'github://marianopeck/OSSubprocess:master/repository'; load. And I am getting this error: However, I am getting this error: File Not Found: 'File @ /Users/mariano/Trabajo/PharoConsortium/imagenes/github-cache/marianopeck/OSSubprocess/master/marianopeck-OSSubprocess-18ae52f/repository/OSSubprocess-Tests.package/monticello.meta/version' And doing a ls i get: ls -la /Users/mariano/Trabajo/PharoConsortium/imagenes/github-cache/marianopeck/OSSubprocess/master/marianopeck-OSSubprocess-18ae52f/repository/OSSubprocess-Tests.package/monticello.meta/ -rw-r--r-- 1 mariano staff 55 Jan 13 14:03 categories.st -rw-r--r-- 1 mariano staff 0 Jan 13 14:03 initializers.st -rw-r--r-- 1 mariano staff 27 Jan 13 14:03 package There is no 'version' file as this guy is trying to load. The package was saved using GitFileTree. Thanks in advacne -- Mariano http://marianopeck.wordpress.com

Jan. 13, 2016

Re: [Pharo-dev] Bad layoutFrame>>#hash

by Stephan Eggermont

Name: SLICE-Issue-17363-LayoutFrame-fractions-0--0-corner-1--1--LayoutFrame-identity-should-be-true-and-it-is-not-StephanEggermont.2 Author: StephanEggermont Time: 13 January 2016, 6:06:01.571074 pm UUID: 9a5e9ae3-1357-4bfb-921a-3762d57402fd Ancestors: Dependencies: Morphic-Base-StephanEggermont.529 Better hash both in distribution and in working with Float coordinates hash ^(((((((( self species hash + leftFraction hash) hashMultiply + leftOffset hash) hashMultiply + topFraction hash) hashMultiply + topOffset hash) hashMultiply + rightFraction hash) hashMultiply + rightOffset hash) hashMultiply + bottomFraction hash) hashMultiply + bottomOffset hash) hashMultiply

Jan. 13, 2016

Re: [Pharo-dev] Problem with gitfiletree numeration

by Ben Coman

>>>>> 2016-01-13 13:12 GMT+01:00 Mariano Martinez Peck >>>>> <marianopeck(a)gmail.com>: >>>>>> >>>>>> Hi guys, >>>>>> >>>>>> I wanted to know how you manage this situation. >>>>>> I had my already existing project in shub repo. Last version was >>>>>> OSSubprocess-MarianoMartinezPeck.43. I then created a github repo, cloned >>>>>> it, and then with gitfiletree I commit for the first time. >>>>>> >>>>>> The problem is that the commit I did with GitFileTree received this MC >>>>>> version: OSSubprocess-MarianoMartinezPeck.1. Normally I would not care. But >>>>>> in this case I do care because every in a while I would like to move/publish >>>>>> some versions from github to shub. And OSSubprocess-MarianoMartinezPeck.1 >>>>>> has 2 problems: >>>>>> >>>>>> 1) It has an older version number but newer contents >>>>>> >>>>>> 2) It's number is not unique. So if I copy versions created from >>>>>> github to shub, they would override those versiones created in shub (like >>>>>> the very old OSSubprocess-MarianoMartinezPeck.1 from shub) ?? >>>>>> >>>>>> >>>>>> How do you normally solve this? >>>>> On Wed, Jan 13, 2016 at 10:46 PM, David Allouche <david(a)allouche.net> wrote: > > Removing commits from a git branch is only really problematic if there are > outstanding, unmerged branches out there, since it tends to cause false > merge conflicts. > > Locals clones of the public repository WILL complain about a divergence, but > they can be fixed by "git pull --force". That is probably acceptable in your > context, since you appear to be in a "botched history" situation. > > Taking a step back, any distributed version control that uses explicit > revision numbers for ordering is broken by design. Yes, Monticello, I am > looking at you. > > That was one of the design mistakes of GNU Arch, and the reason why all the > DVCS that followed it (bzr, hg, git) identify revisions by UUIDs and define > ordering exclusively by the ancestry graph. Experience has also shown that > using content-based UUIDs like hg and git is preferable, for performance and > integrity, to using arbitrary UUIDs like bzr did. > > Disclaimer: I am (not yet) familiar with the Monticello model, so I might be > all wrong. But I am quite knowledgeable about DVCS design in general. >From the little I know about Monticello I believe you are correct. Its a known problem - just no-one has got to tackle it yet. I'm not familiar with this space, but you may be interested in Ring [1] , Epicea [2], libgit[3], in-image github[4]. cheers -ben [1] http://rmod.lille.inria.fr/archives/talks/2010-Smalltalks-Uquillas-Ring.pdf [2] http://arxiv.org/pdf/1309.4334.pdf [3] https://github.com/theseion/LibGit [4] http://forum.world.st/Basic-versioning-of-GitHub-repositories-from-within-P…

Jan. 13, 2016

Re: [Pharo-dev] How to get launcher launching Spur images?

by Stephan Eggermont

On 13-01-16 17:09, Serge Stinckwich wrote: > Great ! Works for me now with the last version on mac os x. > > Maybe new binary version for windows and mac should be provide here for newbies: > https://ci.inria.fr/pharo/view/Launcher/ I've committed a new configuration, promoting this to #stable and using the latest versions of dependencies. It is not yet really friendly enough for newbies, but that's a next step Stephan

Jan. 13, 2016

Re: [Pharo-dev] Bad layoutFrame>>#hash

by David Allouche

> On 12 Jan 2016, at 20:59, stepharo <stepharo(a)free.fr> wrote: > > Hi david > > I rad the wikipedia page you mention and this looks a bit obvious to me. I knew this. > now it does not really help fixing the problem you mention. > > Stef Since you asked for itâ¦ The #hash method is used in Pharo to separate objects in bucket-based data structures. It must have one required property which is required data integrity: A. Objects that are equal according to #= must have equal hashes. It should have two desirable properties that are required to support the algorithmic assumptions of bucket-based data structures: B. Objects that are not equal should have different hashes. Ideally, the probability of hash collision should by 1/N where N is the size of hash value space. C. The hash values should spread as much as possible over their value space. For example: ProtoObject>>#identityHash. How these two desirable properties can be implemented depend on the actual distribution of the value used to compute the hash. An object can safely use XOR hashing if its instance variables are all different objects that already provide a hash method with these two properties. For example, an object whose behaviour is defined by several of singleton delegates of different classes that do not override Object>>#hash. But if the instance variables are not guaranteed to have those properties, it is necessary to more thoroughly "mix the bits". For example: SequenceableCollection>>#hash. hash | hash | hash := self species hash. 1 to: self size do: [:i | hash := (hash + (self at: i) hash) hashMultiply]. ^hash The mixing of the bits is done by the combination of addition and hashMultiply. The value of "species hash" does not need to be processed by hashMultiply, because it is probably computed by ProtoObject>>identityHash, and that already provides C. LayoutFrame is a particularly good example of a data structure that should not use XOR hashing. Its instance variables provide none of the required properties: SmallInteger>>#hash is just ^self. In addition, common LayoutFrame instances tend to use pairs of identical values in their instance variables. Like 0@0 corner: 1@1, or Margin fromNumber: 10. A good hash function for LayoutFrame needs to: Get hashes for each instance variable that provides A and B. Combine them in a way that is order-sensitive (to maintain B) and that does some extra mixing (to provide C). Now, we can assume that common values for the instance variables will be instances of SmallInteger, Float, or Fraction. By the way, you can see in Fraction>>#hash, that a comment mentions the assumption that the fraction is already reduced, that is what makes it acceptable to use bitXor. The hash of SmallInteger does provide A and B, but not C. The hash of Float is harder to understand, but tests show that it provide distinct values for 0.5, 0.25 and 0.125. So it hopefully provides B for the range of values of interest to LayoutFrame. Another class that has similar hashing constraints to LayoutFrame is Point. Its hash method is: hash "Hash is reimplemented because = is implemented." ^(x hash hashMultiply + y hash) hashMultiply It does not include species in the computation, which is less than ideal because it favours collisions with objects of different species that have a similar content and a the same #hash algorithm. Finally, it is probably not necessary or useful to use the accessors to get to the instance variables. So a good implementation would be this (untested, there might be a typo or two) hash | hash | hash := self species hash hash := (hash + leftFraction hash) hashMultiply hash := (hash + leftOffset hash) hashMultiply hash := (hash + topFraction hash) hashMultiply hash := (hash + topOffset hash) hashMultiply hash := (hash + rightFraction hash) hashMultiply hash := (hash + rightOffset hash) hashMultiply hash := (hash + bottomFraction hash) hashMultiply hash := (hash + bottomOffset hash) hashMultiply ^ hash I am sure you could have figured that by yourself, by thinking about how hash values are used and by looking at the code of kernel classes, instead of getting offended and turning all defensive. I hope we can both learn from this episode. I do not enjoy antagonising people, but I will not write lengthy messages like this one every time someone questions my thinking. Have a nice day. > Le 11/1/16 10:09, David Allouche a Ã©crit : >> Since it's not obvious why xor-ing is a bad way to produce hash, here is a link that gives some background >> >> https://en.wikipedia.org/wiki/Hash_function#Uniformity >> >>> On 11 Jan 2016, at 10:01, David Allouche <david(a)allouche.net> wrote: >>> >>> I happened to look at the new code for LayoutFrame>>#hash >>> >>> hash >>> ^self species hash bitXor: >>> (self leftFraction bitXor: >>> (self leftOffset bitXor: >>> (self topFraction bitXor: >>> (self topOffset bitXor: >>> (self rightFraction bitXor: >>> (self rightOffset bitXor: >>> (self bottomFraction bitXor: >>> self bottomOffset))))))) >>> >>> This is a terrible, terrible way to compute a hash. >>> >>> 0 xor 0 = 1 xor 1 = 2 xor 2 = etc. >>> >>> NEVER compute hashes with xor, that's wrong, and it causes horrible, hard to debug, performance bugs down the road. >>> >>> SequenceableCollection>>#hash looks more like a correct way of doing it. I do not know what is the correct, efficient way to reuse this logic in LayoutFrame>>#hash. >>> >>> By the way, how do you guys do code reviews for code integrated into the core? >>> >> >> > >

Jan. 13, 2016

Re: [Pharo-dev] How to get launcher launching Spur images?

by Serge Stinckwich

Great ! Works for me now with the last version on mac os x. Maybe new binary version for windows and mac should be provide here for newbies: https://ci.inria.fr/pharo/view/Launcher/ Thank you guys. On Wed, Jan 13, 2016 at 4:46 PM, Blondeau Vincent <vincent.blondeau(a)worldline.com> wrote: > >> -----Message d'origine----- >> De : Pharo-dev [mailto:pharo-dev-bounces@lists.pharo.org] De la part de >> stepharo >> EnvoyÃ© : mercredi 13 janvier 2016 16:37 >> Ã : Pharo Development List >> Objet : Re: [Pharo-dev] How to get launcher launching Spur images? >> >> So what is the conclusion? >> Can anybody get the launcher open both prespur and spur images? > > I can. You can try the latest version. It should work. > > Vincent >> >> Stef >> >> >> Le 13/1/16 13:16, Blondeau Vincent a Ã©crit : >> > I confirm it works under W7 with Spur and not spur images. >> > Thanks ! >> > >> > I think https://github.com/pharo-project/pharo-launcher/issues/1 can be >> closed now? >> > >> > Vincent >> > >> >> -----Message d'origine----- >> >> De : Pharo-dev [mailto:pharo-dev-bounces@lists.pharo.org] De la part >> >> de Stephan Eggermont EnvoyÃ© : mercredi 13 janvier 2016 12:35 Ã : >> >> pharo-dev(a)lists.pharo.org Objet : Re: [Pharo-dev] How to get launcher >> >> launching Spur images? >> >> >> >> On 13-01-16 12:25, Blondeau Vincent wrote: >> >>> Under Windows, this cmd is working: >> >>> OSProcess command: $" asString, vmCommand , '" "' , imagePath, '"'. >> >>> Does it work under Mac (with real double quotes and not 2 single >> quotes)? >> >>> If no, we should do something that is platform dependent.. >> >> Yes, it works. Please confirm if version 87 works for you >> >> >> >> Stephan >> >> >> >> >> > >> > >> > Ce message et les piÃ¨ces jointes sont confidentiels et rÃ©servÃ©s Ã l'usage >> exclusif de ses destinataires. Il peut Ã©galement Ãªtre protÃ©gÃ© par le secret >> professionnel. Si vous recevez ce message par erreur, merci d'en avertir >> immÃ©diatement l'expÃ©diteur et de le dÃ©truire. L'intÃ©gritÃ© du message ne >> pouvant Ãªtre assurÃ©e sur Internet, la responsabilitÃ© de Worldline ne pourra >> Ãªtre recherchÃ©e quant au contenu de ce message. Bien que les meilleurs >> efforts soient faits pour maintenir cette transmission exempte de tout virus, >> l'expÃ©diteur ne donne aucune garantie Ã cet Ã©gard et sa responsabilitÃ© ne >> saurait Ãªtre recherchÃ©e pour tout dommage rÃ©sultant d'un virus transmis. >> > >> > This e-mail and the documents attached are confidential and intended >> solely for the addressee; it may also be privileged. If you receive this e-mail >> in error, please notify the sender immediately and destroy it. As its integrity >> cannot be secured on the Internet, the Worldline liability cannot be triggered >> for the message content. Although the sender endeavours to maintain a >> computer virus-free network, the sender does not warrant that this >> transmission is virus-free and will not be liable for any damages resulting >> from any virus transmitted. >> > > > > Ce message et les piÃ¨ces jointes sont confidentiels et rÃ©servÃ©s Ã l'usage exclusif de ses destinataires. Il peut Ã©galement Ãªtre protÃ©gÃ© par le secret professionnel. Si vous recevez ce message par erreur, merci d'en avertir immÃ©diatement l'expÃ©diteur et de le dÃ©truire. L'intÃ©gritÃ© du message ne pouvant Ãªtre assurÃ©e sur Internet, la responsabilitÃ© de Worldline ne pourra Ãªtre recherchÃ©e quant au contenu de ce message. Bien que les meilleurs efforts soient faits pour maintenir cette transmission exempte de tout virus, l'expÃ©diteur ne donne aucune garantie Ã cet Ã©gard et sa responsabilitÃ© ne saurait Ãªtre recherchÃ©e pour tout dommage rÃ©sultant d'un virus transmis. > > This e-mail and the documents attached are confidential and intended solely for the addressee; it may also be privileged. If you receive this e-mail in error, please notify the sender immediately and destroy it. As its integrity cannot be secured on the Internet, the Worldline liability cannot be triggered for the message content. Although the sender endeavours to maintain a computer virus-free network, the sender does not warrant that this transmission is virus-free and will not be liable for any damages resulting from any virus transmitted. -- Serge Stinckwich UCBN & UMI UMMISCO 209 (IRD/UPMC) Every DSL ends up being Smalltalk http://www.doesnotunderstand.org/

Jan. 13, 2016

Re: [Pharo-dev] 17348 Enhance shortcut learnability

by Cyril Ferlicot D.

Le 12/01/2016 21:03, Henrik Nergaard a Ã©crit : > Hi Stef, > > > > Something like this? (see attachment) > > > > Best regards, > > Henrik > > Hi, I think it would be cool to also have a setting to get it with an #inform: instead of a full Morph. I would like to get a reminder of the shortcuts but not in all my screen. A little popup at the bottom left is less invasive. So I think that we should be able to get both. What do you think ? -- Cyril Ferlicot http://www.synectique.eu 165 Avenue Bretagne Lille 59000 France

Jan. 13, 2016

Re: [Pharo-dev] How to get launcher launching Spur images?

by Cyril Ferlicot D.

Le 13/01/2016 16:36, stepharo a Ã©crit : > So what is the conclusion? > Can anybody get the launcher open both prespur and spur images? > > Stef > > > Since more than one week I can on Windows and Linux :) -- Cyril Ferlicot http://www.synectique.eu 165 Avenue Bretagne Lille 59000 France

Jan. 13, 2016