November 2014 - Pharo-users

Glamour stream presentations
by Evan Donahue Nov. 12, 2014

Nov. 12, 2014

Hello, I was just wondering if it was possible to use list/table presentations (or an analogous presentation) in Glamour to display streams that load on demand as you page through them (rather than loading all entries into memory before displaying the first page). If not, does anyone have any tips on the best way to go about creating one? Thanks, Evan

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Anyone having a Rserve client?
by phil＠highoctane.be Nov. 12, 2014

Nov. 12, 2014

I am doing some R work and wanted to integrate with Pharo. Is there any support for Rserve around? http://www.rforge.net/Rserve/dev.html At this point I am doing OProcess style stuff with littler but Rserve would be cooler. There are binding for Ruby and Python. e.g. http://pythonhosted.org//pyRserve/ https://github.com/ralhei/pyRserve Stats are becoming bigger and bigger and the leader of the pack is R. DHB is fine and I do use some of it but let's face it, it is nowhere near the power of R... Phil

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Memoization Question
by Torsten Bergmann Nov. 12, 2014

Nov. 12, 2014

Werner Kassens wrote: >Hi, >now this a nice idea, especially the memoizedUsing:cache idea. i would >really appreciate it, if that would be MIT licenced. >werner It already is, thanks to the permission of author John Cromartie who answered us today. Both methods are in a slice already: Details in https://pharo.fogbugz.com/f/cases/14458 Thx T.

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String representation of Class
by Hilaire Nov. 12, 2014

Nov. 12, 2014

Hi, Dr. Geo script are becoming first class citizen -- before it was just a method hooked to an existing DrGeoUserScripts class ; then, it was easy to export the script method as a string to include it in the XML sketch file. Now to save a Dr. Geo sketch using a script, the whole script class needs to be embedded in the sketch XML representation. Is it possible to export a whole class as a string, then import it back from a string representation to a class? Thanks Hilaire -- Dr. Geo - http://drgeo.eu iStoa - http://istoa.drgeo.eu

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Re: [Pharo-users] Is there a way to store workspace 'gists' in Pharo?
by Andy Burnett Nov. 11, 2014

Nov. 11, 2014

Stef said: << I usually create a method and a class. because script do not compose well. >> á§ > > Thanks, that sounds interesting. And, just for clarity, do you mean that you create a single class e.g. MyGists and then create methods for each of your useful snippets? Or, is there a benefit in creating a class per gist? Cheers

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Re: [Pharo-users] Memoization Question
by Torsten Bergmann Nov. 11, 2014

Nov. 11, 2014

Phil wrote: >thanks for the pointer. >Now, how do I use that? First: create a method BlockClosure>>#memoized in your Pharo image (see https://gist.github.com/jcromartie/2705526) memoized "returns memoized version of an unary function" | cache | cache := Dictionary new. ^ [ :x | cache at: x ifAbsentPut: [ self value: x ] ]! So the idea of #memoized is to return a new "outer" block who evaluates the original block only when the computation of the inner block was not yet done/the result of the inner evaluation is not yet cached. As you see from the comment it works for "unary functions" which would mean it works for "one argument blocks". Simple example: |square memo | square:= [:x | Transcript show: 'Processing'. x * x]. memo := square memoized. memo value: 2. memo value: 3. memo value: 2. The Transcript only shows "Processing" two times instead of three times, so only for the first two #value: calls we have to calculate x * x. For the last evaluation on the memo block (with argument 2 again) the result is already known from the cache, so the square block is not evaluated again. Instead the cached result could be returned which could be faster than doing the computation again. x*x is only an example - this "memoization" can usually speed up when a block is costly (performancewise) and is often called with the same arguments. A precondition (for this caching) is that the block evalutes the same way/returns the same result for the same input argument. You also try the two prepared workspaces in Pharo: Non-memoized version: http://ws.stfx.eu/5ZE87XSFL9IH Memoized Version: http://ws.stfx.eu/QLQLSLT7PZ4C Hope this makes it more clear. This simple example is a nice performance trick and shows again the power of Smalltalk and block closures. Dont know about the license - but we could ask author John Cromartie for MIT license to include this simple method into the standard image. I will try to contact him. Bye T.

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Is there a way to store workspace 'gists' in Pharo?
by Andy Burnett Nov. 11, 2014

Nov. 11, 2014

>From time to time I write a workspace script that I would like to keep. Obviously, I could save them to a file, but I was wondering if there was a way of saving them in the image, and browsing them in some friendly way? Cheers Andy á§

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Memoization Question
by Torsten Bergmann Nov. 10, 2014

Nov. 10, 2014

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Re: [Pharo-users] Ploting all history of the commits in a Monticello repository
by Stephan Eggermont Nov. 10, 2014

Nov. 10, 2014

You might get some inspiration by taking a look at http://smalltalkhub.com/#!/~StephanEggermont/DeprecationFinder Stephan

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Re: [Pharo-users] Is there a way to store workspace 'gists' in Pharo?
by Andy Burnett Nov. 10, 2014

Nov. 10, 2014

á§ Doru said <<< If you work with Pharo 4, they should already be saved in a play-cache folder. >> Great, I shall go and experiment. Cheers Andy

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