Re: [Pharo-dev] ZnBufferedReadStream and #upToAll:
Hi Sven, I am really curious why you need it ? > This came up for me when I was trying to parse out pieces of a PDF file. As you likely know, the PDF format has both text and binary information encoded within it. I had used #upToAll: in the past to find sequences of "magic bytes" that don't occur in the middle of a file. It seems that the buffered read stream is what you get if you send #binaryReadStream to a FileReference. But you're right — I could just convert streams and do it that way (if you have other techniques you use, please send along). #upToAll: would definitely be complicated to implement in the buffered version! On Mon, Mar 18, 2019 at 5:11 AM Stephan Eggermont wrote: > ducasse wrote: > > > > I imagine that sven did not add it because on infinite stream it does > not make sense. > > Now it would be good to see how we can have useful extensions. But I let > this to sven. > > That sounds like something that would be useful to make explicit: > isInfinite, with blocking, returning nil, returning null objects, or > returning errors as possible expected behaviors? > > Stephan > > > > > -- Eric
Re: [Pharo-dev] ZnBufferedReadStream and #upToAll:
ducasse wrote: > > I imagine that sven did not add it because on infinite stream it does not > make sense. > Now it would be good to see how we can have useful extensions. But I let this > to sven. That sounds like something that would be useful to make explicit: isInfinite, with blocking, returning nil, returning null objects, or returning errors as possible expected behaviors? Stephan
Re: [Pharo-dev] ZnBufferedReadStream and #upToAll:
> On 17 Mar 2019, at 18:28, Benoit St-Jean wrote: > > If that was the case, then it makes no sense to implement #upTo: but not > #upToAll: , right Indeed :) > > On 2019-03-17 10:37, ducasse wrote: >> Was there a conscious decision not to include the #upToAll: method >> onZnBufferedReadStream?. This method is really useful for parsing files -- >> finding sub-patterns of bytes, etc. Perhaps #upToAll: is not the idiomatic >> way to do this, but I found it very useful to use in the plain old >> ReadStream classes. >> I imagine that sven did not add it because on infinite stream it does not >> make sense. >> Now it would be good to see how we can have useful extensions. But I let >> this to sven. >
Re: [Pharo-dev] ZnBufferedReadStream and #upToAll:
--- Begin Message --- If that was the case, then it makes no sense to implement #upTo: but not #upToAll: , right On 2019-03-17 10:37, ducasse wrote: Was there a conscious decision not to include the #upToAll: method onZnBufferedReadStream?. This method is really useful for parsing files -- finding sub-patterns of bytes, etc. Perhaps #upToAll: is not the idiomatic way to do this, but I found it very useful to use in the plain old ReadStream classes. I imagine that sven did not add it because on infinite stream it does not make sense. Now it would be good to see how we can have useful extensions. But I let this to sven. --- End Message ---
Re: [Pharo-dev] ZnBufferedReadStream and #upToAll:
Eric, Someone wrote a clean implementation of #upToAll: that does not use #position: - I forgot who - but it can be found in ZnCharacterReadStream>>#upToAll: I guess this could be copied over to ZnBufferedReadStream. The main reason that I was against #upToAll: was the implementation using #position: - but what Stef says it also very true: if you do not find what you are looking for, you will read up to end, which is not possible with network streams - you will hang. I also try to minimise the stream API in the newer streams, which is hard because the existing API is so broad. Personally, I never needed #upToAll: during parsing (I also always limit lookahead to 1). I am really curious why you need it ? Most users of #upToAll: search for CRLF, for which I would use a line reader class like ZnLineReader or ZnFastLineReader. Another point is that, if you absolutely need everything that is in the classic ReadStream (which is much more than a stream as it holds a collection of all its elements), in most cases, you could read your content first (assuming it is of known size) and wrap a classic stream around it. Sven > On 17 Mar 2019, at 15:45, Eric Gade wrote: > > Thanks Stef, > > I imagine that sven did not add it because on infinite stream it does not > make sense. > > Just to clarify my earlier email, I got here was by calling > `'/path/to/some/file' asFileReference binaryReadStream` which responds with > the ZnBufferedReadStream. I expected to be able to use something like > #upToAll: to find binary-formatted headers etc within some encoding > structure. It's entirely possible that this was the wrong expectation! > > On Sun, Mar 17, 2019 at 10:38 AM ducasse wrote: > Hi eric > > > Hi all, > > > > Was there a conscious decision not to include the #upToAll: method > > onZnBufferedReadStream?. This method is really useful for parsing files -- > > finding sub-patterns of bytes, etc. Perhaps #upToAll: is not the idiomatic > > way to do this, but I found it very useful to use in the plain old > > ReadStream classes. > > I imagine that sven did not add it because on infinite stream it does not > make sense. > Now it would be good to see how we can have useful extensions. But I let this > to sven. > > > > Sub-question: if I wanted to implement something like this and make a PR, > > would I be submitting to the Pharo dev repository or the Zinc repository? > > Right now to sven repo. In the future we want to have better tools to sync > back from a project to its components. > > Stef > > > > -- > > Eric > > > > > > -- > Eric
Re: [Pharo-dev] ZnBufferedReadStream and #upToAll:
Thanks Stef, I imagine that sven did not add it because on infinite stream it does not > make sense. > Just to clarify my earlier email, I got here was by calling `'/path/to/some/file' asFileReference binaryReadStream` which responds with the ZnBufferedReadStream. I expected to be able to use something like #upToAll: to find binary-formatted headers etc within some encoding structure. It's entirely possible that this was the wrong expectation! On Sun, Mar 17, 2019 at 10:38 AM ducasse wrote: > Hi eric > > > Hi all, > > > > Was there a conscious decision not to include the #upToAll: method > onZnBufferedReadStream?. This method is really useful for parsing files -- > finding sub-patterns of bytes, etc. Perhaps #upToAll: is not the idiomatic > way to do this, but I found it very useful to use in the plain old > ReadStream classes. > > I imagine that sven did not add it because on infinite stream it does not > make sense. > Now it would be good to see how we can have useful extensions. But I let > this to sven. > > > > Sub-question: if I wanted to implement something like this and make a > PR, would I be submitting to the Pharo dev repository or the Zinc > repository? > > Right now to sven repo. In the future we want to have better tools to sync > back from a project to its components. > > Stef > > > > -- > > Eric > > > > -- Eric
Re: [Pharo-dev] ZnBufferedReadStream and #upToAll:
Hi eric > Hi all, > > Was there a conscious decision not to include the #upToAll: method > onZnBufferedReadStream?. This method is really useful for parsing files -- > finding sub-patterns of bytes, etc. Perhaps #upToAll: is not the idiomatic > way to do this, but I found it very useful to use in the plain old ReadStream > classes. I imagine that sven did not add it because on infinite stream it does not make sense. Now it would be good to see how we can have useful extensions. But I let this to sven. > > Sub-question: if I wanted to implement something like this and make a PR, > would I be submitting to the Pharo dev repository or the Zinc repository? Right now to sven repo. In the future we want to have better tools to sync back from a project to its components. Stef > > -- > Eric
