Thank you, Sven! (I asked the question on StackOverflow) And also let me thank you for NeoJSON, NeoCSV and Zinc, which I use a lot and which are a joy to use! Also the documentation is very good and helps a lot. Your code works well and I save a bit of memory by avoiding intermediary data structures, but still this operation uses a lot more memory than I had expected (the example file I use is 80 MB). I tried to parse with PetitParser but the results were similar. I guess, i have to learn to find out were all the memory goes. Best regards, Martin. Sven Van Caekenberghe-2 wrote
(I don't do StackOverflow)
Reading the 'format' is easy, just keep on doing #next for each JSON expression (whitespace is ignored).
| data reader | data := '{"smalltalk": "cool"} {"pharo": "cooler"}'. reader := NeoJSONReader on: data readStream. Array streamContents: [ :out | [ reader atEnd ] whileFalse: [ out nextPut: reader next ] ].
Preventing intermediary data structures is easy too, use streaming.
| client reader data networkStream | (client := ZnClient new) streaming: true; url: 'https://github.com/NYPL-publicdomain/data-and-utilities/blob/master/items/pd...'; get. networkStream := ZnCharacterReadStream on: client contents. reader := NeoJSONReader on: networkStream. data := Array streamContents: [ :out | [ reader atEnd ] whileFalse: [ out nextPut: reader next ] ]. client close. data.
It took a couple of seconds, it is 80MB+ over the network for 50K items after all.
HTH,
Sven
On 21 Jan 2016, at 12:02, Esteban Lorenzano <
estebanlm@
> wrote:
Hi,
there is a question I donât know how to answer.
http://stackoverflow.com/questions/34904337/how-to-parse-ndjson-in-pharo-wit...
Transcript:
I want to parse ndjson (newline delimited json) data with NeoJSON on Pharo Smalltalk.
ndjson data looks like this:
{"smalltalk": "cool"} {"pharo": "cooler"} At the moment I convert my file stream to a string, split it on newline and then parse the single parts using NeoJSON. This seems to use an unnecessary (and extremely huge) amount of memory and time, probably because of converting streams to strings and vice-versa all the time. What would be an efficient way to do this task?
Takers? Esteban
Screen Shot 2016-01-21 at 13.33.57.png (480K) <http://forum.world.st/attachment/4873112/0/Screen%20Shot%202016-01-21%20at%2...;
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