August 2009 - Pharo-dev - lists.pharo.org

[Pharo-project] [update] 10414
by Torsten Bergmann Aug. 13, 2009

Aug. 13, 2009

>Reorganize unit tests in a more modular way So I can delete this from my task list. Thanks! Bye Torsten -- Jetzt kostenlos herunterladen: Internet Explorer 8 und Mozilla Firefox 3 - sicherer, schneller und einfacher! http://portal.gmx.net/de/go/chbrowser

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[Pharo-project] Complex number support discussion
by Ken.Dickey Aug. 13, 2009

Aug. 13, 2009

Igor Stasenko > P.S. diving into complex plane uncovers many potential pitfalls to those > who expecting a certain behavior of mathematical functions over a real > numbers. In first place square and square root. > It is good that with introduction of a complex numbers we can be sure that > x sqrt squared = x for any real x. > > The complex numbers gives us a impression that from now on, the square > function and squared root functions is reversable. But they are not for a > complex numbers. > In practice this means, that one, who using a complex math in his code, > should know well the properties of complex numbers, because this is not so > trivial as with real numbers & school algebra. And such people, basically > don't need the things with questionable or controversial behavior such as > #< operators on a complex plane. Then the aim of Complex package developer > should be to not introduce more confusion to people who is not using/learnt > the complex numbers, and leave attempts to help people who can - because > they could care for themselves well. I guess here I go to high school physics, where electricity and magnetism use complex numbers and relativity uses hyperbolic trig. [Perhaps 1st year physics if your high school did not cover this]. My own experience is that adapting to floating point lossage was far more painful for me than learning 2d mathematics. Again, we can remove Complex totally and make that, hyperbolic trig, ln, and so forth into loadable packages. I would recommend that the error reports for sqrt and ln (if kept) of negative numbers make mention that a loadable package exists to give the expected functionality. A minimal base image (lacking even tools, perhaps even Morphic) is certainly useful in the build process at some point. I suspect there are those who would make such an image even smaller by removing fractions and perhaps even floats. My own preference is to leverage meta-programming aspects (traits, live code, intelligent toolsets) because I think that is where Pharo/Squeak excels. I am certainly happy to pay additional computational cost for better approximations to math (e.g. interval mathematics) because I like the system to tell me where the deep and shallow waters are. A factor of two or even ten slower sounds like a lot, but as speeds continue to double every 18 months, getting the right answers rather than "the wrong answer fast" is why one puts up with slower runtime systems. $0.02, -KenD PS: Thanks all for the helpful suggestions on tightening up the math. I will take a closer look at the branch cuts and so forth.

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[Pharo-project] Dumb question about inspectors
by Schwab,Wilhelm K Aug. 13, 2009

Aug. 13, 2009

Hello all, What makes inspectors prompt about discarding changes? Typically, I want to be told that I am about to lose changes to a browser source pane or a workspace, but almost always, I want inspectors to dumpt their content w/o a modal step. Is that behavior available at present? What preferences would I need to set? Bill

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[Pharo-project] PackageInfo>>addMethod:
by Alexandre Bergel Aug. 13, 2009

Aug. 13, 2009

This method is defined as: -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= addMethod: aMethodReference (self includesClass: aMethodReference class) ifTrue: [self addCoreMethod: aMethodReference] ifFalse: [self addExtensionMethod: aMethodReference] -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= I would have expected #actualClass to be sent to aMethodReference. This method has been written a long time ago, it probably not relevant to fix the bug, since method extension are handled by Monticello. Alexandre -- _,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;: Alexandre Bergel http://www.bergel.eu ^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;.

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[Pharo-project] Problem with new Inspector
by Mariano Martinez Peck Aug. 13, 2009

Aug. 13, 2009

Hi folks: I have a problem with the new inspector. To reproduce: 1) Go to a workspace. 2) Type ScriptLoader or any other class and inspect it. 3) If I want to sends messages to THAT object, it seems the place to do it is in the pane that is above on the right. Is this correct? The problem is that there the right button doesn't work. So, I can only use shortcuts. This is not good for newbie people. In addition, not all the commands are accessible by a shortcut. Any has the same problem? If so, I will open a bug ticket. Best, Mariano

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[Pharo-project] [Ann] RFB/VNC fully configurable by code.
by Miguel Enrique CobÃ¡ Martinez Aug. 13, 2009

Aug. 13, 2009

I have uploaded a new version of RFB to Lukas repo: http://source.lukas-renggli.ch/unsorted for you to test. This new version can be fully configured by code. In fact the RFBServer that manages the GUI menu has been moved to a new class RFBServerGUI. Also, the log is now handled by a dedicated class RFBLog. The implementation of the server is now using the singleton pattern because at any time just a server can be running. Known bugs (known to me, surely it has more that I don't know and are a result of my modifications to the code): - When you unload the class with Monticello, with the server running, the unload method of the class isn't called and the server doesn't restore the Display and Sensor clases to the original ones of the image (non RFB-enabled Display and Sensor). For the moment, if you want to unload the code, be sure to stop the server before the unload. - It brokes the class WAVNCController. The method isServerRunning it is: isServerRunning ^self serverInstance notNil but with this new version of RFB should be: isServerRunning ^self serverInstance isRunning. I have tested it on pharo1.0beta-10401web09.07.5 and pharo core 10408 and it works ok. Please test it and tell me if you find errors or different behavior that expected or intended. I duplicate here part of the RFBServer class comment for the examples of use:

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[Pharo-project] Socket>>connectTo:port: fail
by Serge Stinckwich Aug. 13, 2009

Aug. 13, 2009

Hi all, do some modifications occurs recently in the socket classes ? Because when i'm trying to do : | socket | socket := Socket newTCP. socket connectTo: #[127 0 0 1] port:6665. I have a DNU now : ByteArray>>doesNotUnderstand:#port: I'm using the last Pharo. Thank you, -- Serge Stinckwich UMI UMMISCO 209 (IRD/UPMC), Hanoi, Vietnam Smalltalkers do: [:it | All with: Class, (And love: it)] http://doesnotunderstand.org/

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[Pharo-project] Sideways marketing of pharo, seaside, etc.
by Lawson English Aug. 13, 2009

Aug. 13, 2009

Hey all, I'm in one of my manic brainstorming moods and whilest I'm working on a baby interface between Second Life and Squeak, it dawns on me that there is a huge potential for evangelicalism on your part here: One of hte myriad complains Second LIfe power users have is that the build-in programming tools are extremely limited. There are numerous options for plugins as with Eclipse and emacs (I believe) but they all run as standalone tools with no easy integration with the 3D virtual world experience, which is hte main reason why people bother to script things in SL in the first place: they have interactive feedback with potentialky thousands of other people. The point being that seaside runs just fine on localhost and the builtin SL browser works just fine with everything seaside I have tested. If someone wanted to entice potentially 100,000 Second LIfe users to install seaside, implementing a nice LSL scripting interface in a seaside webpage, complete with syntax coloring, databases of scripts, version control, etc etc, would go a long way toards convincing the Second Life powerusers, at least, that seaside is a worthwhile install. If/when I get my interface to the client-server packets proxy working, one could see potential for many more elaborate uses for squeak/seaside and Second LIfe. (interop between SL and Cobalt/Croquet is left as an exercise for the reader ;-)) Anyway, if someone with a talent for writing editor code wanted to look at the existing external LSL scripting editors and port something to squeak for use on a webpage in seaside, I can almost promise you that squeak/seaside useage would go up by a huge, HUGE factor. Such a project is beyond me, personally due to my lack of formal education, etc., but it should be a worthy project for anyone wishing to promote seaside/smalltalk use. Feel free to ask any questions, privately if appropriate. Lawson English LEnglish5 (at) cox [dot] net Saijanai Kuhn in Second Life

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Re: [Pharo-project] Extending #< to compare all numbers
by Ken.Dickey Aug. 13, 2009

Aug. 13, 2009

"Schwab,Wilhelm K" <bschwab(a)anest.ufl.edu> > Floating point is not always what it seems. Â Hence my comment that IEEE floats get "the wrong answer fast". I have used interval math, continued fractions, and linear fractional transforms (a.k.a. exact reals). I agree that each representation has its challenges. Let's talk for a second about integers. 0 = (0+0i) --> true 1 = (1+0i) --> true 0 < 1 --> true (0+0i) < (1+0i) --> ?? which answer here gives me the least surprise ?? To put it another way (A = a) --> true (B = b) --> true (A < B) --> true (a < b) --> ?? what do you expect to see here ?? > By extension, I argue that > computer-represented complex numbers are not always what they seem, only > more so. Â Agreements: computers don't do math well. Computers approximate math. We would prefer to get the best approximations possible and be told when we are in deep waters. There are math systems (e.g. using interval arithmetic) which either complain that they can't come up with a sensible answer (all the bits are roundoff error) or go back and recompute with higher precision numeric representations in order to get X digits of correct precision. I am _not_ proposing to make Pharo into such a system. > Intuition resulting from lots of exposure to mathematicians suggests that > they consider this non-trivial but well-known. I don't consider "What Every Computer Scientist Should Know About Floating-Point Arithmetic" trivial -- especially for us non-mathematician users of numbers. [ http://docs.sun.com/source/806-3568/ncg_goldberg.html ] > If I am reading this correctly, defining $< is making a promise we can't > keep, or perhaps we simply should not try. Again, I am using unit tests as a fixed point. I want "if A=a and B=b and A<B then a<b" to work as I expect. I consider anything else to be deeply broken. > If you can find something that claims to produce a sensible ordering of > complex numbers, please post a reference. Â For now, my sense is that such a > thing cannot exist. I posted what I consider a sensible ordering which unit tests the property I care about. It happens to be a total ordering (not that I really care). I can certainly remove Complex>>< from the code, but I deeply dislike breaking basic logic on integers. I would prefer to have something more meaningful than "mathematicians can't agree on a theoretical ordering of complex numbers, so practical logic must fail". Do you really not believe that (0+0i) = 0 ?? Why, such numbers must be imaginary!! ;^) -KenD

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[Pharo-project] Packages that load in Pharo [WAS] [Ann] RFB/VNC fully configurable by code.
by Mariano Martinez Peck Aug. 13, 2009

Aug. 13, 2009

Miguel created this page: http://code.google.com/p/pharo/wiki/PackagesTestedInPharo so that we can add there all the packages that load (and work) ok in Pharo. I trying to add some but I found a problem: there is a column called "Package version". I have a same project (for example SqueakDBX) with several Packages in the same monticello repository. There isn't a version for a repository, but for a package. So, what should I do if I have several packages? Best, Mariano ---------- Forwarded message ---------- From: Miguel Enrique CobÃ¡ Martinez <miguel.coba(a)gmail.com> Date: 2009/8/12 Subject: Re: [Pharo-project] [Ann] RFB/VNC fully configurable by code. To: Pharo-project(a)lists.gforge.inria.fr El miÃ©, 12-08-2009 a las 18:18 -0100, Mariano Martinez Peck escribiÃ³: > > > What sort of packages should be put there? For example, I am woring in > SqueakDBX and Glorp and both of them work there. However, they are not > dev tools or something like. Thus, I don't understand which type or > packages should be added. Every package that loads and runs ok on pharo. This will motivate to port even more packages. I hope it will be a catalyzer because if we can show that a lot of packages are already running ok on pharo, the stability and maturity of pharo will make it a good platform to base new software and to port software from other smalltalk versions. So, if you have a package that load/runs, please by any means add it. -- Miguel CobÃ¡ http://miguel.leugim.com.mx _______________________________________________ Pharo-project mailing list Pharo-project(a)lists.gforge.inria.fr http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project

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