Why is readStream on SequenceableCollection and not on Collection?
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Why is readStream on SequenceableCollection and not on Collection?
 
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Dear list, is there a specific reason readStream is defined on SequenceableCollection and not on Collection? I want to for instance stream over a Set (in a non determined order).
I tried to do readStream on a Set, but got an error that copyFrom:to: was not defined on Set; so: ReadStream>>on: aCollection I think should read:
ReadStream>>on: aSequenceableCollection Or should I always use: collect: select: detect: protocols? Any thoughts on this? Kind Regards Bart -- imagination is more important than knowledge - Albert Einstein Logic will get you from A to B. Imagination will take you everywhere - Albert Einstein Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning. - Albert Einstein The true sign of intelligence is not knowledge but imagination. - Albert Einstein However beautiful the strategy, you should occasionally look at the results. - Sir Winston Churchill It's not enough that we do our best; sometimes we have to do what's required. - Sir Winston Churchill _______________________________________________ Pharo-project mailing list [hidden email] http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project |
Re: Why is readStream on SequenceableCollection and not on Collection?
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did you try with nile?
because I forgot (of course doing too many things) but the difference between squeak and VW was that we could not have a stream on something else than string and array. Now this may have changed in squeak with the work of levente or nicolas. Stef On Aug 24, 2010, at 1:11 PM, Bart Gauquie wrote: > Dear list, > > is there a specific reason readStream is defined on SequenceableCollection and not on Collection? > > I want to for instance stream over a Set (in a non determined order). > > I tried to do readStream on a Set, but got an error that copyFrom:to: was not defined on Set; so: > > ReadStream>>on: aCollection > > I think should read: > > ReadStream>>on: aSequenceableCollection > > > Or should I always use: collect: select: detect: protocols? > > Any thoughts on this? > > Kind Regards > > Bart > > -- > imagination is more important than knowledge - Albert Einstein > Logic will get you from A to B. Imagination will take you everywhere - Albert Einstein > Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning. - Albert Einstein > The true sign of intelligence is not knowledge but imagination. - Albert Einstein > However beautiful the strategy, you should occasionally look at the results. - Sir Winston Churchill > It's not enough that we do our best; sometimes we have to do what's required. - Sir Winston Churchill > _______________________________________________ > Pharo-project mailing list > [hidden email] > http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project _______________________________________________ Pharo-project mailing list [hidden email] http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project |
Re: Why is readStream on SequenceableCollection and not on Collection?
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This cropped up in Dolphin some years back. IIRC, OA's answer was that streams historically worked on only Array and maybe something else. Having said that, they relaxed a constraint because it was harmless and a good idea.
I'm not sure about streaming over a set; lack of order means that it might be tricky to maintain a reasonable position?? ________________________________________ From: [hidden email] [[hidden email]] On Behalf Of Stéphane Ducasse [[hidden email]] Sent: Tuesday, August 24, 2010 7:18 AM To: [hidden email] Subject: Re: [Pharo-project] Why is readStream on SequenceableCollection and not on Collection? did you try with nile? because I forgot (of course doing too many things) but the difference between squeak and VW was that we could not have a stream on something else than string and array. Now this may have changed in squeak with the work of levente or nicolas. Stef On Aug 24, 2010, at 1:11 PM, Bart Gauquie wrote: > Dear list, > > is there a specific reason readStream is defined on SequenceableCollection and not on Collection? > > I want to for instance stream over a Set (in a non determined order). > > I tried to do readStream on a Set, but got an error that copyFrom:to: was not defined on Set; so: > > ReadStream>>on: aCollection > > I think should read: > > ReadStream>>on: aSequenceableCollection > > > Or should I always use: collect: select: detect: protocols? > > Any thoughts on this? > > Kind Regards > > Bart > > -- > imagination is more important than knowledge - Albert Einstein > Logic will get you from A to B. Imagination will take you everywhere - Albert Einstein > Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning. - Albert Einstein > The true sign of intelligence is not knowledge but imagination. - Albert Einstein > However beautiful the strategy, you should occasionally look at the results. - Sir Winston Churchill > It's not enough that we do our best; sometimes we have to do what's required. - Sir Winston Churchill > _______________________________________________ > Pharo-project mailing list > [hidden email] > http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project _______________________________________________ Pharo-project mailing list [hidden email] http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project _______________________________________________ Pharo-project mailing list [hidden email] http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project |
Re: Why is readStream on SequenceableCollection and not on Collection?
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2010/8/24 Schwab,Wilhelm K <[hidden email]>:
> This cropped up in Dolphin some years back. IIRC, OA's answer was that streams historically worked on only Array and maybe something else. Having said that, they relaxed a constraint because it was harmless and a good idea. > > I'm not sure about streaming over a set; lack of order means that it might be tricky to maintain a reasonable position?? > Exactly, the Stream would hardly be positionable, unless you use a sort of OrderedSet... A ReadWriteStream would be problematic for the same reasons. What would be the interest of such a Stream ? (I mean something more than what just you can do with #do:or #add:) Nicolas > > > ________________________________________ > From: [hidden email] [[hidden email]] On Behalf Of Stéphane Ducasse [[hidden email]] > Sent: Tuesday, August 24, 2010 7:18 AM > To: [hidden email] > Subject: Re: [Pharo-project] Why is readStream on SequenceableCollection and not on Collection? > > did you try with nile? > because I forgot (of course doing too many things) but the difference between squeak and VW was that > we could not have a stream on something else than string and array. Now this may have changed in squeak with the work of levente > or nicolas. > Stef > > On Aug 24, 2010, at 1:11 PM, Bart Gauquie wrote: > >> Dear list, >> >> is there a specific reason readStream is defined on SequenceableCollection and not on Collection? >> >> I want to for instance stream over a Set (in a non determined order). >> >> I tried to do readStream on a Set, but got an error that copyFrom:to: was not defined on Set; so: >> >> ReadStream>>on: aCollection >> >> I think should read: >> >> ReadStream>>on: aSequenceableCollection >> >> >> Or should I always use: collect: select: detect: protocols? >> >> Any thoughts on this? >> >> Kind Regards >> >> Bart >> >> -- >> imagination is more important than knowledge - Albert Einstein >> Logic will get you from A to B. Imagination will take you everywhere - Albert Einstein >> Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning. - Albert Einstein >> The true sign of intelligence is not knowledge but imagination. - Albert Einstein >> However beautiful the strategy, you should occasionally look at the results. - Sir Winston Churchill >> It's not enough that we do our best; sometimes we have to do what's required. - Sir Winston Churchill >> _______________________________________________ >> Pharo-project mailing list >> [hidden email] >> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project > > > _______________________________________________ > Pharo-project mailing list > [hidden email] > http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project > > _______________________________________________ > Pharo-project mailing list > [hidden email] > http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project > _______________________________________________ Pharo-project mailing list [hidden email] http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project |
Re: Why is readStream on SequenceableCollection and not on Collection?
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Den 24.08.2010 17:58, skrev Nicolas Cellier: > 2010/8/24 Schwab,Wilhelm K <[hidden email]>: > >> This cropped up in Dolphin some years back. IIRC, OA's answer was that streams historically worked on only Array and maybe something else. Having said that, they relaxed a constraint because it was harmless and a good idea. >> >> I'm not sure about streaming over a set; lack of order means that it might be tricky to maintain a reasonable position?? >> >> > Exactly, the Stream would hardly be positionable, unless you use a > sort of OrderedSet... > A ReadWriteStream would be problematic for the same reasons. > > What would be the interest of such a Stream ? > (I mean something more than what just you can do with #do:or #add:) > > Nicolas I don't quite see what use could would find in a stream of a non-sequenced source that is not better served by using a different abstraction, or the source itself.. Cheers, Henry _______________________________________________ Pharo-project mailing list [hidden email] http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project |
Re: Why is readStream on SequenceableCollection and not on Collection?
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On Wed, Aug 25, 2010 at 10:38 AM, Henrik Johansen <[hidden email]> wrote:
Ok, but why can you then do a collect:[] / select:[] / do: [] over a set? It also iterates over all the elements. So why is it then strange to have a readstream over a set? I'm not saying it should be a positionable stream. But I also agree that is more logical to only do a ReadStream over a SequenceableCollection if you take into account positions ... Maybe change the code so that it only accepts a SequenceableCollection?
Haven't tried Nile yet. Kind Regards, Bart _______________________________________________ Pharo-project mailing list [hidden email] http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project |
Re: Why is readStream on SequenceableCollection and not on Collection?
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Den 25.08.2010 12:58, skrev Bart Gauquie:
Yes they iterate of the elements, but they don't really care about which. sequence the elements are in. Sure you can write a block to pass to them which does, but I doubt you'd want to use that with a Set or a Dictionary. #next, #nextPut:, #upTo: and the rest of the Stream protocol certainly do care what sequence the elements are in. Cheers, Henry _______________________________________________ Pharo-project mailing list [hidden email] http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project |
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