Writing into stream from another stream
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Writing into stream from another stream
 
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Hi.
Do we have simple method to write data between streams? I want something like: I always used loop for this. But maybe we have something suitable. Otherwise lets introduce it. Best regards, Denis |
Re: Writing into stream from another stream
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ZnUtils class>>#streamFrom:to: ?
> On 29 Mar 2018, at 11:22, Denis Kudriashov <[hidden email]> wrote: > > Hi. > > Do we have simple method to write data between streams? > > I want something like: > > writeStream nextPutAllFrom: readStream > > I always used loop for this. But maybe we have something suitable. Otherwise lets introduce it. > > Best regards, > Denis |
Re: Writing into stream from another stream
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I use writeStream nextPutAll: readStream contents but it is quite silly...to convert stream -> string -> stream On Thu, Mar 29, 2018 at 11:45 AM, Sven Van Caekenberghe <[hidden email]> wrote: ZnUtils class>>#streamFrom:to: ? |
Re: Writing into stream from another stream
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In reply to this post by Sven Van Caekenberghe-2
2018-03-29 11:45 GMT+02:00 Sven Van Caekenberghe <[hidden email]>: ZnUtils class>>#streamFrom:to: ? Yes, it gives feature which I want. But it's too Java style. What you think to move it to stream itself? And with what message name?
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Re: Writing into stream from another stream
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> On 29 Mar 2018, at 14:34, Denis Kudriashov <[hidden email]> wrote: > > > 2018-03-29 11:45 GMT+02:00 Sven Van Caekenberghe <[hidden email]>: > ZnUtils class>>#streamFrom:to: ? > > Yes, it gives feature which I want. But it's too Java style. > What you think to move it to stream itself? And with what message name? This was written in a specific context, to be efficient. I don't know if it is general enough for broad use. Yes it could be more OO to not make it a utility method, but on the other hand, where would you put it ? I am hesitant to make the Stream API bigger ;-) > > On 29 Mar 2018, at 11:22, Denis Kudriashov <[hidden email]> wrote: > > > > Hi. > > > > Do we have simple method to write data between streams? > > > > I want something like: > > > > writeStream nextPutAllFrom: readStream > > > > I always used loop for this. But maybe we have something suitable. Otherwise lets introduce it. > > > > Best regards, > > Denis > > > |
Re: Writing into stream from another stream
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2018-03-29 14:40 GMT+02:00 Sven Van Caekenberghe <[hidden email]>:
In read streams we already have:
So I would put new method in ReadStream (#readIntoStream: ?). I am hesitant to make the Stream API bigger ;-) We already have this method in Utils class. So it is here but in strange hidden place.
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Re: Writing into stream from another stream
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There are two different questions: - expressivenessI'm not at all convinced that we should focus too much on such optimization. It sounds like we could provide the two: ... or provide a way to negotiate the transfer (size of chunked buffers, etc...) It's a long time since I did not check Xtreams, but wasn't there a reified Buffer that could/would be the effective actor of such transfer? 2018-03-29 15:02 GMT+02:00 Denis Kudriashov <[hidden email]>:
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Re: Writing into stream from another stream
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In reply to this post by Denis Kudriashov
I agree we should not have Utils class.
On Thu, Mar 29, 2018 at 3:02 PM, Denis Kudriashov <[hidden email]> wrote: > 2018-03-29 14:40 GMT+02:00 Sven Van Caekenberghe <[hidden email]>: >> >> >> >> > On 29 Mar 2018, at 14:34, Denis Kudriashov <[hidden email]> wrote: >> > >> > >> > 2018-03-29 11:45 GMT+02:00 Sven Van Caekenberghe <[hidden email]>: >> > ZnUtils class>>#streamFrom:to: ? >> > >> > Yes, it gives feature which I want. But it's too Java style. >> > What you think to move it to stream itself? And with what message name? >> >> This was written in a specific context, to be efficient. I don't know if >> it is general enough for broad use. Yes it could be more OO to not make it a >> utility method, but on the other hand, where would you put it ? > > > In read streams we already have: > > > readInto: aCollection startingAt: startIndex count: n > > > So I would put new method in ReadStream (#readIntoStream: ?). > >> >> I am hesitant to make the Stream API bigger ;-) > > > We already have this method in Utils class. So it is here but in strange > hidden place. > >> >> > > On 29 Mar 2018, at 11:22, Denis Kudriashov <[hidden email]> >> > > wrote: >> > > >> > > Hi. >> > > >> > > Do we have simple method to write data between streams? >> > > >> > > I want something like: >> > > >> > > writeStream nextPutAllFrom: readStream >> > > >> > > I always used loop for this. But maybe we have something suitable. >> > > Otherwise lets introduce it. >> > > >> > > Best regards, >> > > Denis >> > >> > >> > >> >> > |
Re: Writing into stream from another stream
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In reply to this post by Nicolas Cellier
Hi nicolas
I like your proposal. Stef On Thu, Mar 29, 2018 at 5:44 PM, Nicolas Cellier <[hidden email]> wrote: > There are two different questions: > - expressiveness > - efficiency > > Real efficiency of transfer (without any intermediate copy) is only > guaranteed in very rare cases > (if the target collection of write stream is same species as source > collection of read stream, and there are no transform in any of the > intermediate wrapper streams, then a direct bulk transfer of the form > targetCollection replaceFrom:to:with: sourceCollection startingAt: is > possible) > I'm not at all convinced that we should focus too much on such optimization. > > The fact that we have at least two choices, let the readStream drive the > operation, or let the writeStream do it, is a smell. > It sounds like we could provide the two: > aReadStream writeContentsTo: aWriteStream. > aWriteStream readContentsFrom: aReadStream. > ... and then let the programmer decide (maybe there is a more optimal path). > ... or provide a way to negotiate the transfer (size of chunked buffers, > etc...) > > Unless there is a more symetrical solution. > It's a long time since I did not check Xtreams, but wasn't there a reified > Buffer that could/would be the effective actor of such transfer? > > Nicolas > > > 2018-03-29 15:02 GMT+02:00 Denis Kudriashov <[hidden email]>: >> >> 2018-03-29 14:40 GMT+02:00 Sven Van Caekenberghe <[hidden email]>: >>> >>> >>> >>> > On 29 Mar 2018, at 14:34, Denis Kudriashov <[hidden email]> >>> > wrote: >>> > >>> > >>> > 2018-03-29 11:45 GMT+02:00 Sven Van Caekenberghe <[hidden email]>: >>> > ZnUtils class>>#streamFrom:to: ? >>> > >>> > Yes, it gives feature which I want. But it's too Java style. >>> > What you think to move it to stream itself? And with what message name? >>> >>> This was written in a specific context, to be efficient. I don't know if >>> it is general enough for broad use. Yes it could be more OO to not make it a >>> utility method, but on the other hand, where would you put it ? >> >> >> In read streams we already have: >> >> >> readInto: aCollection startingAt: startIndex count: n >> >> >> So I would put new method in ReadStream (#readIntoStream: ?). >> >>> >>> I am hesitant to make the Stream API bigger ;-) >> >> >> We already have this method in Utils class. So it is here but in strange >> hidden place. >> >>> >>> > > On 29 Mar 2018, at 11:22, Denis Kudriashov <[hidden email]> >>> > > wrote: >>> > > >>> > > Hi. >>> > > >>> > > Do we have simple method to write data between streams? >>> > > >>> > > I want something like: >>> > > >>> > > writeStream nextPutAllFrom: readStream >>> > > >>> > > I always used loop for this. But maybe we have something suitable. >>> > > Otherwise lets introduce it. >>> > > >>> > > Best regards, >>> > > Denis >>> > >>> > >>> > >>> >>> >> > |
Re: Writing into stream from another stream
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In reply to this post by Denis Kudriashov
> On 29 Mar 2018, at 15:02, Denis Kudriashov <[hidden email]> wrote: > > 2018-03-29 14:40 GMT+02:00 Sven Van Caekenberghe <[hidden email]>: > > > > On 29 Mar 2018, at 14:34, Denis Kudriashov <[hidden email]> wrote: > > > > > > 2018-03-29 11:45 GMT+02:00 Sven Van Caekenberghe <[hidden email]>: > > ZnUtils class>>#streamFrom:to: ? > > > > Yes, it gives feature which I want. But it's too Java style. > > What you think to move it to stream itself? And with what message name? > > This was written in a specific context, to be efficient. I don't know if it is general enough for broad use. Yes it could be more OO to not make it a utility method, but on the other hand, where would you put it ? > > In read streams we already have: > > readInto: aCollection startingAt: startIndex count: n > > So I would put new method in ReadStream (#readIntoStream: ?). > > I am hesitant to make the Stream API bigger ;-) > > We already have this method in Utils class. So it is here but in strange hidden place. Not all streams inherit from ReadStream, far from it. So if you add it there, you add it to 'the stream API' that every other stream-like class has to implement. Hence it is a burden, for limited gain. I also do not specifically like Util classes, but this is a more special case. The operation belongs to both parties involved. You could define a StreamCopier to do the job. The way it is implemented now, it does not extend the stream API, that is worth something too. Anyway, we are just discussing ideas. > > > On 29 Mar 2018, at 11:22, Denis Kudriashov <[hidden email]> wrote: > > > > > > Hi. > > > > > > Do we have simple method to write data between streams? > > > > > > I want something like: > > > > > > writeStream nextPutAllFrom: readStream > > > > > > I always used loop for this. But maybe we have something suitable. Otherwise lets introduce it. > > > > > > Best regards, > > > Denis > > > > > > |
Re: Writing into stream from another stream
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In reply to this post by Nicolas Cellier
Hi Nicolas
2018-03-29 17:44 GMT+02:00 Nicolas Cellier <[hidden email]>:
I like this idea.
Xtreams provides nice API to "pipe" multiple streams. But as I remember the Buffer was internal detail hidden from your. Idea was to reuse internal stream arrays to minimize garbage (or something like this).
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