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

Re: [Pharo-users] Downloading a .tar.gz file with Zinc in Pharo-1.4(Summer)

by Sven Van Caekenberghe

Hmm, interesting ! I have to study this further and read the specs. On 17 Aug 2012, at 22:29, Paul DeBruicker <pdebruic(a)gmail.com> wrote: > Hi Sven, > > Updating certainly lets me download it but I'm then faced with the problem that the resulting file is a tar archive and is no longer gzipped. > > > E.g. > > wget http://www.iana.org/time-zones/repository/tzdata-latest.tar.gz > > > paul@paul-laptop:~/pharo/Pharo-1.4$ls -la tzdata-latest.tar.gz > -rw-rw-r-- 1 paul paul 206251 Aug 2 21:08 tzdata-latest.tar.gz > > paul@paul-laptop:~/pharo/Pharo-1.4$ file tzdata-latest.tar.gz > tzdata-latest.tar.gz: gzip compressed data, from Unix, max compression > > > > > and after running the download in pharo, as you saw, the file is 686kB. > > paul@paul-laptop:~/pharo/Pharo-1.4$ls -la tzdata-latest.tar.gz > -rw-rw-r-- 1 paul paul 686080 Aug 17 13:23 tzdata-latest.tar.gz > > paul@paul-laptop:~/pharo/Pharo-1.4$ file tzdata-latest.tar.gz > tzdata-latest.tar.gz: POSIX tar archive (GNU) > > > Is there a way to not unzip the file when downloading it through Pharo? I admit its a minor quibble, but its not expected. > > > Thanks > > Paul > > > On 08/17/2012 11:47 AM, Sven Van Caekenberghe wrote: >> Paul, >> >> On 17 Aug 2012, at 19:55, Paul DeBruicker <pdebruic(a)gmail.com> wrote: >> >>> Thanks for looking into it Sven >>> >>> Pharo 1.4 (Summer) 14457. Eliots 2585 VM. Ubuntu 12.04 64bit. >> >> You seem to have hit a problem in Zn that was recently fixed (beginning of august), if you update Zn it works. >> >> Regards, >> >> Sven >> >>> On 08/17/2012 10:49 AM, Sven Van Caekenberghe wrote: >>>> Works for me, Pharo 2.0 ##20201 >>>> >>>> [sven@voyager:~/smalltalk]$ tar tvfz tzdata-latest.tar.gz >>>> -rw-r--r-- 0 0 0 44941 Jul 19 02:45 africa >>>> -rw-r--r-- 0 0 0 15827 Jul 19 02:30 antarctica >>>> -rw-r--r-- 0 0 0 112760 Jul 25 16:13 asia >>>> -rw-r--r-- 0 0 0 68423 Jul 25 16:40 australasia >>>> -rw-r--r-- 0 0 0 121390 Jul 25 16:13 europe >>>> -rw-r--r-- 0 0 0 135756 Jul 25 16:13 northamerica >>>> -rw-r--r-- 0 0 0 73854 Jul 25 16:13 southamerica >>>> -rw-r--r-- 0 0 0 1190 Jul 19 02:30 pacificnew >>>> -rw-r--r-- 0 0 0 2955 Jul 19 02:30 etcetera >>>> -rw-r--r-- 0 0 0 4083 Jul 19 02:30 backward >>>> -rw-r--r-- 0 0 0 1546 Jul 19 02:30 systemv >>>> -rw-r--r-- 0 0 0 393 Jul 19 02:30 factory >>>> -rw-r--r-- 0 0 0 19306 Jul 19 02:30 solar87 >>>> -rw-r--r-- 0 0 0 19324 Jul 19 02:30 solar88 >>>> -rw-r--r-- 0 0 0 19600 Jul 19 02:30 solar89 >>>> -rw-r--r-- 0 0 0 4326 Jul 19 02:30 iso3166.tab >>>> -rw-r--r-- 0 0 0 19913 Jul 19 02:30 zone.tab >>>> -rw-r--r-- 0 0 0 3186 Jul 25 16:13 leapseconds >>>> -rw-r--r-- 0 0 0 680 Jul 19 02:30 yearistype.sh >>>> [sven@voyager:~/smalltalk]$ file !$ >>>> file tzdata-latest.tar.gz >>>> tzdata-latest.tar.gz: POSIX tar archive (GNU) >>>> [sven@voyager:~/smalltalk]$ ls -la !$ >>>> ls -la tzdata-latest.tar.gz >>>> -rw-r--r--@ 1 sven sven 686080 Aug 17 19:47 tzdata-latest.tar.gz >>>> >>>> What image, platform, VM are you on ? >>>> >>>> On 17 Aug 2012, at 19:19, Paul DeBruicker <pdebruic(a)gmail.com> wrote: >>>> >>>>> I'm trying to download the Olson time-zone database so Chronos can automatically update its ruleset. >>>>> >>>>> In a workspace, when I do: >>>>> >>>>> ZnClient new >>>>> url:'http://www.iana.org/time-zones/repository/tzdata-latest.tar.gz'; >>>>> downloadTo:FileDirectory default pathName. >>>>> >>>>> >>>>> I get a SubscriptOutOfBounds error . The file is ~207kB. The GzipReadStream>#getFirstBuffer gets the first 65,536 bytes and then hits the out of bounds error. Moving the limit in that method to 262,144 (1 << 18 rather than 1 << 16) gets us to another error from which I don't know the right way to proceed. >>>>> >>>>> >>>>> I think that because its an content type 'application/x-tar' it shouldn't hit the GzipReadStream class at all but should just be a ReadStream that does not get decompressed in the image and instead sent straight to the disk. I'm not sure how to implement that though inside Zinc and would welcome ideas to try. >>>>> >>>>> Thanks >>>>> >>>>> Paul >>>>> >>>> >>>> >>> >>> >> >> > >

Aug. 17, 2012

uploaded something into MetacelloRepository by mistake.

by Paul DeBruicker

Hi - I just uploaded ChronosTimeZoneUtilities-PaulDeBruicker.4.mcz into the squeaksource MetacelloRepository by mistake. Could someone please delete it from there? I'll put it in the proper place right now. Thanks.

Aug. 17, 2012

Re: [Pharo-users] Downloading a .tar.gz file with Zinc in Pharo-1.4(Summer)

by Paul DeBruicker

Hi Sven, Updating certainly lets me download it but I'm then faced with the problem that the resulting file is a tar archive and is no longer gzipped. E.g. wget http://www.iana.org/time-zones/repository/tzdata-latest.tar.gz paul@paul-laptop:~/pharo/Pharo-1.4$ls -la tzdata-latest.tar.gz -rw-rw-r-- 1 paul paul 206251 Aug 2 21:08 tzdata-latest.tar.gz paul@paul-laptop:~/pharo/Pharo-1.4$ file tzdata-latest.tar.gz tzdata-latest.tar.gz: gzip compressed data, from Unix, max compression and after running the download in pharo, as you saw, the file is 686kB. paul@paul-laptop:~/pharo/Pharo-1.4$ls -la tzdata-latest.tar.gz -rw-rw-r-- 1 paul paul 686080 Aug 17 13:23 tzdata-latest.tar.gz paul@paul-laptop:~/pharo/Pharo-1.4$ file tzdata-latest.tar.gz tzdata-latest.tar.gz: POSIX tar archive (GNU) Is there a way to not unzip the file when downloading it through Pharo? I admit its a minor quibble, but its not expected. Thanks Paul On 08/17/2012 11:47 AM, Sven Van Caekenberghe wrote: > Paul, > > On 17 Aug 2012, at 19:55, Paul DeBruicker <pdebruic(a)gmail.com> wrote: > >> Thanks for looking into it Sven >> >> Pharo 1.4 (Summer) 14457. Eliots 2585 VM. Ubuntu 12.04 64bit. > > You seem to have hit a problem in Zn that was recently fixed (beginning of august), if you update Zn it works. > > Regards, > > Sven > >> On 08/17/2012 10:49 AM, Sven Van Caekenberghe wrote: >>> Works for me, Pharo 2.0 ##20201 >>> >>> [sven@voyager:~/smalltalk]$ tar tvfz tzdata-latest.tar.gz >>> -rw-r--r-- 0 0 0 44941 Jul 19 02:45 africa >>> -rw-r--r-- 0 0 0 15827 Jul 19 02:30 antarctica >>> -rw-r--r-- 0 0 0 112760 Jul 25 16:13 asia >>> -rw-r--r-- 0 0 0 68423 Jul 25 16:40 australasia >>> -rw-r--r-- 0 0 0 121390 Jul 25 16:13 europe >>> -rw-r--r-- 0 0 0 135756 Jul 25 16:13 northamerica >>> -rw-r--r-- 0 0 0 73854 Jul 25 16:13 southamerica >>> -rw-r--r-- 0 0 0 1190 Jul 19 02:30 pacificnew >>> -rw-r--r-- 0 0 0 2955 Jul 19 02:30 etcetera >>> -rw-r--r-- 0 0 0 4083 Jul 19 02:30 backward >>> -rw-r--r-- 0 0 0 1546 Jul 19 02:30 systemv >>> -rw-r--r-- 0 0 0 393 Jul 19 02:30 factory >>> -rw-r--r-- 0 0 0 19306 Jul 19 02:30 solar87 >>> -rw-r--r-- 0 0 0 19324 Jul 19 02:30 solar88 >>> -rw-r--r-- 0 0 0 19600 Jul 19 02:30 solar89 >>> -rw-r--r-- 0 0 0 4326 Jul 19 02:30 iso3166.tab >>> -rw-r--r-- 0 0 0 19913 Jul 19 02:30 zone.tab >>> -rw-r--r-- 0 0 0 3186 Jul 25 16:13 leapseconds >>> -rw-r--r-- 0 0 0 680 Jul 19 02:30 yearistype.sh >>> [sven@voyager:~/smalltalk]$ file !$ >>> file tzdata-latest.tar.gz >>> tzdata-latest.tar.gz: POSIX tar archive (GNU) >>> [sven@voyager:~/smalltalk]$ ls -la !$ >>> ls -la tzdata-latest.tar.gz >>> -rw-r--r--@ 1 sven sven 686080 Aug 17 19:47 tzdata-latest.tar.gz >>> >>> What image, platform, VM are you on ? >>> >>> On 17 Aug 2012, at 19:19, Paul DeBruicker <pdebruic(a)gmail.com> wrote: >>> >>>> I'm trying to download the Olson time-zone database so Chronos can automatically update its ruleset. >>>> >>>> In a workspace, when I do: >>>> >>>> ZnClient new >>>> url:'http://www.iana.org/time-zones/repository/tzdata-latest.tar.gz'; >>>> downloadTo:FileDirectory default pathName. >>>> >>>> >>>> I get a SubscriptOutOfBounds error . The file is ~207kB. The GzipReadStream>#getFirstBuffer gets the first 65,536 bytes and then hits the out of bounds error. Moving the limit in that method to 262,144 (1 << 18 rather than 1 << 16) gets us to another error from which I don't know the right way to proceed. >>>> >>>> >>>> I think that because its an content type 'application/x-tar' it shouldn't hit the GzipReadStream class at all but should just be a ReadStream that does not get decompressed in the image and instead sent straight to the disk. I'm not sure how to implement that though inside Zinc and would welcome ideas to try. >>>> >>>> Thanks >>>> >>>> Paul >>>> >>> >>> >> >> > >

Aug. 17, 2012

Re: [Pharo-users] HowTo make a Morph that accepts dropped files and folders and produces a new FileSystem FileReference in Pharo 1.4

by Ricardo Moran

On Fri, Aug 17, 2012 at 11:34 AM, Helene Bilbo < thereluctantprogrammer(a)fastmail.fm> wrote: (...) > Or can you share an image where this is working? > No problem. Here it is: https://dl.dropbox.com/u/43706148/Pharo-1.4-DropHandler.zip Cheers, Richo > > > -- > View this message in context: > http://forum.world.st/HowTo-make-a-Morph-that-accepts-dropped-files-and-fol… > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. > >

Aug. 17, 2012

Re: [Pharo-users] best practices for model/view dependencies

by Bernardo Ezequiel Contreras

Vassili Bykov's blog at cincom http://www.cincomsmalltalk.com/userblogs/vbykov/blogView?entry=3310034894 On Fri, Aug 17, 2012 at 2:32 PM, StÃ©phane Ducasse <stephane.ducasse(a)inria.fr > wrote: > > On Aug 17, 2012, at 3:46 PM, Johann Hibschman wrote: > > > I'm still relatively new to Pharo and to Smalltalk in general, > > welcome :) > > > and > > I've hit a situation where I'd like a model that notifies dependent > > views when it changes. > > > > Classically, it looks like this was done through #addDependent:, > > #update, #changed, #release and friends. I don't need more than a > > symbol message and an associated object, so I could live with that > > API, but I don't quite understand #release. > > Do not use changed:/update because > - it broadcasts to all the dependents > - you have to build case statement in the update > > > It sounds like originally > > Object class held (non-weak) references to all objects that had > > dependents, so unless the dependents were explicitly released, the > > objects would never be released. I get the impression that at some > > point this was switched to using weak references, so I wouldn't have > > to worry about closed parent/dependent loops, but I can't find this > > explicitly spelled out anywhere. > > > > - Question 1: Does the basic addDependent/etc. system on Pharo use > > weak references? > > You can use on:send:to: on Morph or when: anEventSelector send: > aMessaageSelector to: anObject on object > You can also use Announcement. > > > - Question 2: Am I correct in understanding that the main point of the > > Model class was to avoid having an entry in the Object class variable, > > so a closed parent/dependent loop could be garbage collected? > > This table in the Object is an old idea and we should remove it. > People should use ValueHolder > > > - Question 3: If Pharo uses weak references, is there any point to the > > Model class? > > > > I've also seen some references to the Announcements framework, but I > > can't find as much documentation on it as I can on the "basic" > > Smalltalk dependency mechanism. It seems a bit more complex, with > > actual event classes, but I've not understood it yet. > > In fact you get an object and not only a symbol so you can pass more logic > > > - Question 4: Should I prefer using Announcements for even mostly > trivial cases? > when: anEventSelector > send: aMessaageSelector > to: anObject > > which is should unify with the on:send:to: of Morph > > > - Question 5: What benefits would Announcements give me? > > that you can pass a complex object around. > Read the blog of Vassili on Announcement. > > > > > Any overall pointers would be appreciated as well. > > > > Thanks, > > Johann > > > > > -- Bernardo E.C.

Aug. 17, 2012

Re: [Pharo-users] Downloading a .tar.gz file with Zinc in Pharo-1.4(Summer)

by Sven Van Caekenberghe

Paul, On 17 Aug 2012, at 19:55, Paul DeBruicker <pdebruic(a)gmail.com> wrote: > Thanks for looking into it Sven > > Pharo 1.4 (Summer) 14457. Eliots 2585 VM. Ubuntu 12.04 64bit. You seem to have hit a problem in Zn that was recently fixed (beginning of august), if you update Zn it works. Regards, Sven > On 08/17/2012 10:49 AM, Sven Van Caekenberghe wrote: >> Works for me, Pharo 2.0 ##20201 >> >> [sven@voyager:~/smalltalk]$ tar tvfz tzdata-latest.tar.gz >> -rw-r--r-- 0 0 0 44941 Jul 19 02:45 africa >> -rw-r--r-- 0 0 0 15827 Jul 19 02:30 antarctica >> -rw-r--r-- 0 0 0 112760 Jul 25 16:13 asia >> -rw-r--r-- 0 0 0 68423 Jul 25 16:40 australasia >> -rw-r--r-- 0 0 0 121390 Jul 25 16:13 europe >> -rw-r--r-- 0 0 0 135756 Jul 25 16:13 northamerica >> -rw-r--r-- 0 0 0 73854 Jul 25 16:13 southamerica >> -rw-r--r-- 0 0 0 1190 Jul 19 02:30 pacificnew >> -rw-r--r-- 0 0 0 2955 Jul 19 02:30 etcetera >> -rw-r--r-- 0 0 0 4083 Jul 19 02:30 backward >> -rw-r--r-- 0 0 0 1546 Jul 19 02:30 systemv >> -rw-r--r-- 0 0 0 393 Jul 19 02:30 factory >> -rw-r--r-- 0 0 0 19306 Jul 19 02:30 solar87 >> -rw-r--r-- 0 0 0 19324 Jul 19 02:30 solar88 >> -rw-r--r-- 0 0 0 19600 Jul 19 02:30 solar89 >> -rw-r--r-- 0 0 0 4326 Jul 19 02:30 iso3166.tab >> -rw-r--r-- 0 0 0 19913 Jul 19 02:30 zone.tab >> -rw-r--r-- 0 0 0 3186 Jul 25 16:13 leapseconds >> -rw-r--r-- 0 0 0 680 Jul 19 02:30 yearistype.sh >> [sven@voyager:~/smalltalk]$ file !$ >> file tzdata-latest.tar.gz >> tzdata-latest.tar.gz: POSIX tar archive (GNU) >> [sven@voyager:~/smalltalk]$ ls -la !$ >> ls -la tzdata-latest.tar.gz >> -rw-r--r--@ 1 sven sven 686080 Aug 17 19:47 tzdata-latest.tar.gz >> >> What image, platform, VM are you on ? >> >> On 17 Aug 2012, at 19:19, Paul DeBruicker <pdebruic(a)gmail.com> wrote: >> >>> I'm trying to download the Olson time-zone database so Chronos can automatically update its ruleset. >>> >>> In a workspace, when I do: >>> >>> ZnClient new >>> url:'http://www.iana.org/time-zones/repository/tzdata-latest.tar.gz'; >>> downloadTo:FileDirectory default pathName. >>> >>> >>> I get a SubscriptOutOfBounds error . The file is ~207kB. The GzipReadStream>#getFirstBuffer gets the first 65,536 bytes and then hits the out of bounds error. Moving the limit in that method to 262,144 (1 << 18 rather than 1 << 16) gets us to another error from which I don't know the right way to proceed. >>> >>> >>> I think that because its an content type 'application/x-tar' it shouldn't hit the GzipReadStream class at all but should just be a ReadStream that does not get decompressed in the image and instead sent straight to the disk. I'm not sure how to implement that though inside Zinc and would welcome ideas to try. >>> >>> Thanks >>> >>> Paul >>> >> >> > >

Aug. 17, 2012

Re: [Pharo-users] Downloading a .tar.gz file with Zinc in Pharo-1.4(Summer)

by Paul DeBruicker

I also get the problem with the VM's from inira On 08/17/2012 10:49 AM, Sven Van Caekenberghe wrote: > Works for me, Pharo 2.0 ##20201

Aug. 17, 2012

Re: [Pharo-users] Downloading a .tar.gz file with Zinc in Pharo-1.4(Summer)

by Paul DeBruicker

Thanks for looking into it Sven Pharo 1.4 (Summer) 14457. Eliots 2585 VM. Ubuntu 12.04 64bit. Paul On 08/17/2012 10:49 AM, Sven Van Caekenberghe wrote: > Works for me, Pharo 2.0 ##20201 > > [sven@voyager:~/smalltalk]$ tar tvfz tzdata-latest.tar.gz > -rw-r--r-- 0 0 0 44941 Jul 19 02:45 africa > -rw-r--r-- 0 0 0 15827 Jul 19 02:30 antarctica > -rw-r--r-- 0 0 0 112760 Jul 25 16:13 asia > -rw-r--r-- 0 0 0 68423 Jul 25 16:40 australasia > -rw-r--r-- 0 0 0 121390 Jul 25 16:13 europe > -rw-r--r-- 0 0 0 135756 Jul 25 16:13 northamerica > -rw-r--r-- 0 0 0 73854 Jul 25 16:13 southamerica > -rw-r--r-- 0 0 0 1190 Jul 19 02:30 pacificnew > -rw-r--r-- 0 0 0 2955 Jul 19 02:30 etcetera > -rw-r--r-- 0 0 0 4083 Jul 19 02:30 backward > -rw-r--r-- 0 0 0 1546 Jul 19 02:30 systemv > -rw-r--r-- 0 0 0 393 Jul 19 02:30 factory > -rw-r--r-- 0 0 0 19306 Jul 19 02:30 solar87 > -rw-r--r-- 0 0 0 19324 Jul 19 02:30 solar88 > -rw-r--r-- 0 0 0 19600 Jul 19 02:30 solar89 > -rw-r--r-- 0 0 0 4326 Jul 19 02:30 iso3166.tab > -rw-r--r-- 0 0 0 19913 Jul 19 02:30 zone.tab > -rw-r--r-- 0 0 0 3186 Jul 25 16:13 leapseconds > -rw-r--r-- 0 0 0 680 Jul 19 02:30 yearistype.sh > [sven@voyager:~/smalltalk]$ file !$ > file tzdata-latest.tar.gz > tzdata-latest.tar.gz: POSIX tar archive (GNU) > [sven@voyager:~/smalltalk]$ ls -la !$ > ls -la tzdata-latest.tar.gz > -rw-r--r--@ 1 sven sven 686080 Aug 17 19:47 tzdata-latest.tar.gz > > What image, platform, VM are you on ? > > On 17 Aug 2012, at 19:19, Paul DeBruicker <pdebruic(a)gmail.com> wrote: > >> I'm trying to download the Olson time-zone database so Chronos can automatically update its ruleset. >> >> In a workspace, when I do: >> >> ZnClient new >> url:'http://www.iana.org/time-zones/repository/tzdata-latest.tar.gz'; >> downloadTo:FileDirectory default pathName. >> >> >> I get a SubscriptOutOfBounds error . The file is ~207kB. The GzipReadStream>#getFirstBuffer gets the first 65,536 bytes and then hits the out of bounds error. Moving the limit in that method to 262,144 (1 << 18 rather than 1 << 16) gets us to another error from which I don't know the right way to proceed. >> >> >> I think that because its an content type 'application/x-tar' it shouldn't hit the GzipReadStream class at all but should just be a ReadStream that does not get decompressed in the image and instead sent straight to the disk. I'm not sure how to implement that though inside Zinc and would welcome ideas to try. >> >> Thanks >> >> Paul >> > >

Aug. 17, 2012

Re: [Pharo-users] Downloading a .tar.gz file with Zinc in Pharo-1.4(Summer)

by Sven Van Caekenberghe

Works for me, Pharo 2.0 ##20201 [sven@voyager:~/smalltalk]$ tar tvfz tzdata-latest.tar.gz -rw-r--r-- 0 0 0 44941 Jul 19 02:45 africa -rw-r--r-- 0 0 0 15827 Jul 19 02:30 antarctica -rw-r--r-- 0 0 0 112760 Jul 25 16:13 asia -rw-r--r-- 0 0 0 68423 Jul 25 16:40 australasia -rw-r--r-- 0 0 0 121390 Jul 25 16:13 europe -rw-r--r-- 0 0 0 135756 Jul 25 16:13 northamerica -rw-r--r-- 0 0 0 73854 Jul 25 16:13 southamerica -rw-r--r-- 0 0 0 1190 Jul 19 02:30 pacificnew -rw-r--r-- 0 0 0 2955 Jul 19 02:30 etcetera -rw-r--r-- 0 0 0 4083 Jul 19 02:30 backward -rw-r--r-- 0 0 0 1546 Jul 19 02:30 systemv -rw-r--r-- 0 0 0 393 Jul 19 02:30 factory -rw-r--r-- 0 0 0 19306 Jul 19 02:30 solar87 -rw-r--r-- 0 0 0 19324 Jul 19 02:30 solar88 -rw-r--r-- 0 0 0 19600 Jul 19 02:30 solar89 -rw-r--r-- 0 0 0 4326 Jul 19 02:30 iso3166.tab -rw-r--r-- 0 0 0 19913 Jul 19 02:30 zone.tab -rw-r--r-- 0 0 0 3186 Jul 25 16:13 leapseconds -rw-r--r-- 0 0 0 680 Jul 19 02:30 yearistype.sh [sven@voyager:~/smalltalk]$ file !$ file tzdata-latest.tar.gz tzdata-latest.tar.gz: POSIX tar archive (GNU) [sven@voyager:~/smalltalk]$ ls -la !$ ls -la tzdata-latest.tar.gz -rw-r--r--@ 1 sven sven 686080 Aug 17 19:47 tzdata-latest.tar.gz What image, platform, VM are you on ? On 17 Aug 2012, at 19:19, Paul DeBruicker <pdebruic(a)gmail.com> wrote: > I'm trying to download the Olson time-zone database so Chronos can automatically update its ruleset. > > In a workspace, when I do: > > ZnClient new > url:'http://www.iana.org/time-zones/repository/tzdata-latest.tar.gz'; > downloadTo:FileDirectory default pathName. > > > I get a SubscriptOutOfBounds error . The file is ~207kB. The GzipReadStream>#getFirstBuffer gets the first 65,536 bytes and then hits the out of bounds error. Moving the limit in that method to 262,144 (1 << 18 rather than 1 << 16) gets us to another error from which I don't know the right way to proceed. > > > I think that because its an content type 'application/x-tar' it shouldn't hit the GzipReadStream class at all but should just be a ReadStream that does not get decompressed in the image and instead sent straight to the disk. I'm not sure how to implement that though inside Zinc and would welcome ideas to try. > > Thanks > > Paul >

Aug. 17, 2012

Re: [Pharo-users] best practices for model/view dependencies

by StÃ©phane Ducasse

On Aug 17, 2012, at 3:46 PM, Johann Hibschman wrote: > I'm still relatively new to Pharo and to Smalltalk in general, welcome :) > and > I've hit a situation where I'd like a model that notifies dependent > views when it changes. > > Classically, it looks like this was done through #addDependent:, > #update, #changed, #release and friends. I don't need more than a > symbol message and an associated object, so I could live with that > API, but I don't quite understand #release. Do not use changed:/update because - it broadcasts to all the dependents - you have to build case statement in the update > It sounds like originally > Object class held (non-weak) references to all objects that had > dependents, so unless the dependents were explicitly released, the > objects would never be released. I get the impression that at some > point this was switched to using weak references, so I wouldn't have > to worry about closed parent/dependent loops, but I can't find this > explicitly spelled out anywhere. > > - Question 1: Does the basic addDependent/etc. system on Pharo use > weak references? You can use on:send:to: on Morph or when: anEventSelector send: aMessaageSelector to: anObject on object You can also use Announcement. > - Question 2: Am I correct in understanding that the main point of the > Model class was to avoid having an entry in the Object class variable, > so a closed parent/dependent loop could be garbage collected? This table in the Object is an old idea and we should remove it. People should use ValueHolder > - Question 3: If Pharo uses weak references, is there any point to the > Model class? > > I've also seen some references to the Announcements framework, but I > can't find as much documentation on it as I can on the "basic" > Smalltalk dependency mechanism. It seems a bit more complex, with > actual event classes, but I've not understood it yet. In fact you get an object and not only a symbol so you can pass more logic > - Question 4: Should I prefer using Announcements for even mostly trivial cases? when: anEventSelector send: aMessaageSelector to: anObject which is should unify with the on:send:to: of Morph > - Question 5: What benefits would Announcements give me? that you can pass a complex object around. Read the blog of Vassili on Announcement. > > Any overall pointers would be appreciated as well. > > Thanks, > Johann >

Aug. 17, 2012