- Pharo-users - lists.pharo.org

Pharo - database without database
by Adam Sept. 30, 2015

Sept. 30, 2015

Hello, I was wondering if it is possible for Pharo to load lots of data and query them without using external DB, just using object memory. Well, someting like GemStone/S, but not so sophisticated. I did some research so here is details what I found. I would appreciate if someone can tell me if any points of this agenda can be allready done or need to be programmed, or if this whole idea is waste of time and it is better to use external DB. 1) Object memory limit: Current object memory of Pharo is limited to 4GB. Free version of GemStone/S is also limited to 4GB, so I would rather stick with Pharo until I reach this level. And in the future this limit grow due to 64bit version of VM. 2) Saving to disk: Is it possible to save object or group of objects to disk and ensure consistency? With some transaction mechanism and transaction log? 3) RAM limit: Is it possible to delete objects from memory, move them to the disk and not break its connections to other objects? For example by redirecting object internal ID to some kind of hollow object, that will renew receiver of message from disk if necessary... This approach can also possibly split object memory into more "remote" sources. 4) Indexing: What optimalization for searching current collections in Pharo do? For example: how to store instances of City if I would like to search through it by name and also by its postal code? Is there some library for creating fulltext search (maybe Spotter uses that - I did not study it yet). Have a nice day, and thanks for any answer. Adam

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Pharo 5 update of Grafeo
by Stephan Eggermont Sept. 30, 2015

Sept. 30, 2015

Grafeo is a nice Morphic graph editing toolkit by Eiichiro Ito. It forms the basis for Fluo. https://vimeo.com/80749341 I've updated it for Pharo 5. I had to copy it to StephanEggermont/Documentation, as oohito/Fluo is not writable. Stephan Name: Grafeo-StephanEggermont.64 Author: StephanEggermont Time: 30 September 2015, 9:51:53.670434 am UUID: 5dc871e7-c1ea-4098-95c2-6c5741548ecb Ancestors: Grafeo-EiichiroIto.63 Changes for Pharo 5.0 Replaced deprecated menu methods Fixed one error message

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Dr. Geo script for primary school activity
by Hilaire Sept. 29, 2015

Sept. 29, 2015

Hi, Okay this one is really a complex one[1], but Dr. Geo scripts are definitely not 2 lines of code, but Smalltalk code[2] :) In a few words, it is a sketch for primary school learners. The student must build some expected polygons and the Dr. Geo script provides the appropriate textual and graphic feedback. Video demo: https://plus.google.com/+DrgeoEu/posts/CbXLuWhms8E Hilaire [1] How to decide two collections of points represent the same polygon? And we have to deal with point being Float... [2] Sketch file on request -- Dr. Geo http://drgeo.eu http://google.com/+DrgeoEu

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How to read the first line of content from a Playground?
by phil＠highoctane.be Sept. 29, 2015

Sept. 29, 2015

In the old workspace it was possible to ask for the first line of contents (to show it in a list). With a playground it seems harder... Lots of entries in there. Is there any short way to get that done? TIA Phil

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Question about color
by Offray Vladimir Luna CÃ¡rdenas Sept. 29, 2015

Sept. 29, 2015

Hi, At a local workshop we're working with the Pharo tutorial and we use the classical example of RGB colors for keyword messages. When we use the Prof Stef's example we get the following screenshot: While executing the same color in Wolfram Alpha gives us: As you can see, both colors are pretty different. Which is the reason behind the differences in the color that is shown in Pharo and the one in WA? Cheers, Offray

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Breakpoint ?
by Nic Sept. 29, 2015

Sept. 29, 2015

Hi all, on the ESUG 2014 was a demonstration of Breakpoints in Pharo. Did somebody know what project I can load to get them or how far they are with it? Regards, Nic

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not yet / should be implemented
by Peter UhnÃ¡k Sept. 29, 2015

Sept. 29, 2015

What is the difference? âââââââââââââââââââââââââââââââââââââ *ShouldBeImplemented* I am ShouldBeImplemented, an exception signaled when some method should have been implemented but was not. This is more like a placeholder during development. âââââââââââââââââââââââââââââââââââââ *NotYetImplemented* I am NotYetImplement, an exception signaled when a method is a stub for code that will be implemented in the future. This is used in incremental development, for example when doing Test First development. It is similar to ShouldBeImplemented, with a slightly different meaning. âââââââââââââââââââââââââââââââââââââ There seem to be some slight semantic difference but I'm failing to see it. I can even say "The method should be implemented, but is not yet implemented." It's saying the same thing with different words. Thanks, Peter

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Re: [Pharo-users] Morph: event handler on wrong morph/submorph
by Federico.Balaguer Sept. 28, 2015

Sept. 28, 2015

Thanks a lot! Federico -- View this message in context: http://forum.world.st/Morph-event-handler-on-wrong-morph-submorph-tp4852370… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

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PharoTouch Demo Video
by Marcus Denker Sept. 28, 2015

Sept. 28, 2015

Pharo touch demo with the new OSWindows architecture, touch events, vector graphics using Athens and libsdl2. Thanks the people involved (specifically for the touch project Christopher Coat, Mervan Ougdane, Jan-Baptiste Arnaud, Eric Lepors and Mathieu Lacaton) and to Thales for sponsoring this project. https://www.youtube.com/watch?v=ksyoGItedVg <https://www.youtube.com/watch?v=ksyoGItedVg>

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Dr Geo: A point needs to be animated over a preexisting object?
by Offray Vladimir Luna CÃ¡rdenas Sept. 28, 2015

Sept. 28, 2015

Hi, Here comes again. Sorry I send it from a wrong address. -------- Forwarded Message -------- Subject: Dr Geo: A point needs to be animated over a preexisting object? Date: Mon, 21 Sep 2015 20:09:29 -0500 From: Offray Vladimir Luna CÃ¡rdenas <offray.luna(a)mutabit.com> To: Any question about pharo is welcome <pharo-users(a)lists.pharo.org> Hi, Some of my students are exploring modeling as a tool to understand physical phenomena. In particular they're working on uniform movement. The idea is to take data from a lab experiment on uniform movement and plot it on a geometrical program and then use animation to reproduce the lab movement inside the plotting to see if they can get the analitycal expression which models the movement. The bridge between experimental data and the analytical expression is animation as a way to validate, reconstruct models. We're considering geogebra and DrGeo for this. I'm more familiar with smalltalk that with javascript, but the question we're facing is how to animate a point following a vector direction but going beyond it. Considering the following figure: So the idea is that A, B, C and D are points in a position versus time graph taken from the real lab experiment. "p" is a point which will follow the trajectory of the vector "u", which has the same direction of the segment that goes from A to B (it can be even overlapped) and is animated describing the red trajectory going for p to p' (which has the same x value of D, but a different y value). A way to do it will be put and invisible line that passing from A to B (and beyond) and make the point "p" move on it, but we're wondering if there is a way to just give vector direction and magnitude and make the point move, without creating an explicit line before. Seems that nor geogebra or DrGeo can deal with animating a free object following a (vectorial described) trajectory. Is this possible? Cheers, Offray

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