January 2012 - Pharo-users - lists.pharo.org

Re: [Pharo-users] another confusing result

by Benjamin

On Jan 8, 2012, at 4:16 PM, Larry White wrote: > This may just be me misunderstanding the way it's supposed to work, but I was exploring the method > > combinations: kk atATimeDo: aBlock defined in SequenceableCollection > > 'abcde' combinations: 2 atATimeDo: [:each | Transcript cr; show: each printString]. > produces the expected result: > #($a $b) > #($a $c) > #($a $d) > #($a $e) > #($b $c) > #($b $d) > #($b $e) > #($c $d) > #($c $e) > #($d $e) And here, if you do: 'abcde' combinations: 2 atATimeDo: [:each | each inspect. Transcript cr; show: each printString]. You get inspectors with #($e $e) ... > > but, if you add :each to a collection instead of printing, you get something different. The following code: > res := OrderedCollection new. > 'abcde' combinations: 2 atATimeDo: [:each | res add: each]. > Transcript show: res. > produces: > an OrderedCollection(#($e $e) #($e $e) #($e $e) #($e $e) #($e $e) #($e $e) #($e $e) #($e $e) #($e $e) #($e $e)) > > Thanks again. After a quick look at the methods combinations: kk atATimeDo: aBlock "Take the items in the receiver, kk at a time, and evaluate the block for each combination. Hand in an array of elements of self as the block argument. Each combination only occurs once, and order of the elements does not matter. There are (self size take: kk) combinations." " 'abcde' combinations: 3 atATimeDo: [:each | Transcript cr; show: each printString]" | aCollection | aCollection := Array new: kk. self combinationsAt: 1 in: aCollection after: 0 do: aBlock and combinationsAt: jj in: aCollection after: nn do: aBlock "Choose k of N items and put in aCollection. jj-1 already chosen. Indexes of items are in numerical order, to avoid the same combo being used twice. In this slot, we are allowed to use items in self indexed by nn+1 to self size. nn is the index used for position jj-1." "(1 to: 6) combinationsSize: 3 do: [:each | Transcript cr; show: each printString]" nn+1 to: self size do: [:index | aCollection at: jj put: (self at: index). jj = aCollection size ifTrue: [aBlock value: aCollection] ifFalse: [self combinationsAt: jj + 1 in: aCollection after: index do: aBlock]]. You can see that each step result is store in the same collection. So actually, when you print it it's ok, because it's done before the following step erase the current content of the collection. But then at the end, you get always the same result, it's what the code is supposed to do. Then, I do not think it makes sense, but at least, now I understand why ;) Ben

Jan. 8, 2012

another confusing result

by Larry White

This may just be me misunderstanding the way it's supposed to work, but I was exploring the method combinations: kk atATimeDo: aBlock defined in SequenceableCollection 'abcde' combinations: 2 atATimeDo: [:each | Transcript cr; show: each printString]. produces the expected result: #($a $b) #($a $c) #($a $d) #($a $e) #($b $c) #($b $d) #($b $e) #($c $d) #($c $e) #($d $e) but, if you add :each to a collection instead of printing, you get something different. The following code: res := OrderedCollection new. 'abcde' combinations: 2 atATimeDo: [:each | res add: each]. Transcript show: res. produces: an OrderedCollection(#($e $e) #($e $e) #($e $e) #($e $e) #($e $e) #($e $e) #($e $e) #($e $e) #($e $e) #($e $e)) Thanks again.

Jan. 8, 2012

strange behavior in workspace

by Larry White

I'm messing about with Project Euler problems and have noticed some behavior that I don't understand. This one happens to be very self-contained so I though I'd as for assistance. This code (which doesn't solve the problem, btw) is buggy, but I can't see the bug and I'm beginning to suspect something in the VM or the class libraries. When I execute it, two odd things happen: First, in spite of the block test [sum < 100] whileTrue:[...] it continues to run when sum > 100 (or a million for that matter). Second, the block in the line: (sum isPrime) ifTrue: [ (seq size > bestSeq size) ifTrue: [ bestSeq := seq copy.]] executes even when sum is not a prime number. Any help is appreciated. ------------------------------- "Create a list of primes smaller than a million" primes := OrderedCollection new. 2 to: 999999 do: [ :n | n isPrime ifTrue: [ primes add: n]]. bestSeq := OrderedCollection new. seq := OrderedCollection new. sum := 0. [sum < 100] whileTrue: [ primes do: [:prime | seq add: prime. sum := seq sum. (sum isPrime) ifTrue: [ (seq size > bestSeq size) ifTrue: [ bestSeq := seq copy.]] ] ].

Jan. 8, 2012

[COTDC] 101 - TarArchiveMember

by sean＠clipperadams.com

100 classes done 796 classes remaining Continuing in Compression... Today: TarArchiveMember Comment Of The Day Contest - One Day One Comment Rules: #1: Each day a not commented class is elected. Each day the best comment will be integrated with name of the author(s). #2: If you cannot comment it, deprecate it. Results: http://code.google.com/p/pharo/wiki/CommentOfTheDayContest p.s. this message was sent from a pharo image. Did you know you could easily do that?!

Jan. 8, 2012

Call for translation

by Hilaire Fernandes

Hello, Dr. Geo (http://www.drgeo.eu) is a neat open source application showing the power of Pharo Smalltalk. It is targeted to teachers, parents and kids for all over the world. It is distributed as a portable desktop application and also a XO application for the OLPC kid laptop. As for now it is translated in English, French, German and Spanish. I would love to see more translation from the European house (latin alphabet based, there is still investigation to be done for non latin language). Italian, Portuguese, Swedish, Finland, Dutch, Norwich, Danish... will be nice Translating DrGeo is less than one hour of work[1]. Hilaire [1] http://www.drgeo.eu/community/faq#TOC-How-can-I-translate-Dr.-Geo-in-my-n -- Dr. Geo -- http://www.drgeo.eu

Jan. 7, 2012

Re: [Pharo-users] [ANN][DBX] Phoseydon Beta2

by Sven Van Caekenberghe

Cool ! On 05 Jan 2012, at 21:22, Guillermo Polito wrote: > Hi! > > I'm willing to announce the second beta release of Phoseydon, part of the DBXTalk project, supported by ESUG :). > > It's main new feature is a simple internal dsl to generate entities, so you can create applications from something like: > personEntity := application entityNamed: #Person. > > personEntity > hasString: #nickname; > hasInteger: #age; > > > hasBoolean: #isProgrammer. > > petEntity := application entityNamed: #Pet. > > petEntity > hasString: #nickname. > personEntity hasMany: #Pet as: #pets. > > petEntity hasOne: #Person as: #owner. > > > Also, a little manual is already written in: > http://dbxtalk.smallworks.com.ar/pier/Documentation > > For download: > http://dbxtalk.smallworks.com.ar/pier/Download > > Issues, mails, questions: > http://dbxtalk.smallworks.com.ar/pier/Support > > Cheers, > the DBXTalk Team

Jan. 6, 2012

[COTDC] 100 - GZipConstants

by sean＠clipperadams.com

A new class for the New Year... 99 classes done 797 classes remaining Continuing in Compression... Today: GZipConstants Comment Of The Day Contest - One Day One Comment Rules: #1: Each day a not commented class is elected. Each day the best comment will be integrated with name of the author(s). #2: If you cannot comment it, deprecate it. Results: http://code.google.com/p/pharo/wiki/CommentOfTheDayContest p.s. this message was sent from a pharo image. Did you know you could easily do that?!

Jan. 6, 2012

[ANN][DBX] Phoseydon Beta2

by Guillermo Polito

Hi! I'm willing to announce the second beta release of Phoseydon, part of the DBXTalk project, supported by ESUG :). It's main new feature is a simple internal dsl to generate entities, so you can create applications from something like: personEntity := application entityNamed: #Person. personEntity hasString: #nickname; hasInteger: #age; hasBoolean: #isProgrammer. petEntity := application entityNamed: #Pet. petEntity hasString: #nickname. personEntity hasMany: #Pet as: #pets. petEntity hasOne: #Person as: #owner. Also, a little manual is already written in: http://dbxtalk.smallworks.com.ar/pier/Documentation For download: http://dbxtalk.smallworks.com.ar/pier/Download Issues, mails, questions: http://dbxtalk.smallworks.com.ar/pier/Support Cheers, the DBXTalk Team

Jan. 5, 2012

Re: [Pharo-users] compression example?

by HernÃ¡n Morales Durand

| zip fileName myInputDir | myInputDir := #('Users' 'data' 'files' 'arabic') inject: '' into: [:path :suffix | path, FileDirectory slash , suffix]. zip := ZipArchive new. zip addTree: ( FileDirectory default fullName , myInputDir ) match: [: e | true ]. fileName := 'foo.zip'. zip writeToFileNamed: fileName. 2012/1/2 Larry White <ljw1001(a)gmail.com>: > > zip := ZipArchive new. > Â Â Â Â zipArchive addDirectory: '/Users/data/files/arabic' as: 'arabic'. > fileName := 'Users/data/downloads/foo.zip'. > zip writeToFileNamed: fileName. -- HernÃ¡n Morales Information Technology Manager, Institute of Veterinary Genetics. National Scientific and Technical Research Council (CONICET). La Plata (1900), Buenos Aires, Argentina. Telephone: +54 (0221) 421-1799. Internal: 422 Fax: 425-7980 or 421-1799.

Jan. 5, 2012

compression example?

by Larry White

Hi, I'm trying to read the files in a given directory, add them to a ZipArchive, and write that ZipArchive out to another directory. My code looks like this: zip := ZipArchive new. zipArchive addDirectory: '/Users/data/files/arabic' as: 'arabic'. fileName := 'Users/data/downloads/foo.zip'. zip writeToFileNamed: fileName. I'm getting an archive file with the correct name written out, but I can't access the contents of folder 'arabic'. Do I have to add each of the files in 'arabic' explicitly to the zipArchive? Does anyone know of some example code for this they could point me to? Thanks much and happy new year. Larry

Jan. 2, 2012