- Pharo-dev - lists.pharo.org

Re: [Pharo-project] Issue 3188 in pharo: do we need SecurityManager?

by pharo＠googlecode.com

Comment #2 on issue 3188 by marcus.d...(a)gmail.com: do we need SecurityManager? http://code.google.com/p/pharo/issues/detail?id=3188 We need to integrate Issue 3818 before (changes / cleanups to startup logic)

April 9, 2011

Re: [Pharo-project] Have started an independent developer activity - Thank you

by Sven Van Caekenberghe

On 09 Apr 2011, at 09:34, laurent laffont wrote: > Hi, > > I discovered Smalltalk and Pharo almost three years ago and just after read Chad Fowler book "Passionate Programmer" (1st edition title was "My job went to India"). These have changed my developer life, how I perceive software and that great technology is fun, people doing it more. You're a cool community and I'm proud to be there. > > Now I've started an aside (paid :) independent developer activity thanks to a cool guy. That would not be possible without all the stuff I learn every day from the community and the urge to continue you give me. Great for you Laurent, you absolutely deserve, I wish you success. > Each time I've made a step forward (open a blog, write ProfStef, fix bugs, create PharoCasts) I've been amazed that the generated effects were those described in Passionate Programmer (go read it !) The last chapter is "Go independent" so now I need the sequel ;) > > Special big thank you to StÃ©phane Ducasse - you're crazy :) Long live Pharo ! > > > PS: nice piece of Passionate Programmer: > > When I was in India weeding through hundreds of candidates for only > tens of jobs, the interview team was exhausting itself and running out > of time because of a poor interview-to-hire hit rate. Heads hurting and > eyes red, we held a late-night meeting to discuss a strategic change in the > way we would go through the candidates. We had to either optimize the > process so we could interview more people or somehow interview better > people (or both). With what little was left of my voice after twelve straight > hours of trying to drag answers out of dumbstruck programmers, I argued > for adding Smalltalk to the list of keywords our headhunters were using > to search their rÃ©sumÃ© database. But, nobody knows Smalltalk in India, cried > the human resources director. That was my point. Nobody knew it, and > programming in Smalltalk was a fundamentally different experience than > programming in Java. The varying experience would give candidates a > different level of expectations, and the dynamic nature of the Smalltalk > environment would reshape the way a Java programmer would approach > a problem. My hope was that these factors would encourage a level of > technical maturity that I hadnât been seeing from the candidates Iâd met so > far. > The addition of Smalltalk to the requirements list yielded a candidate pool > that was tiny in contrast to our previous list. These people were diamonds > in the rough. They really understood object-oriented programming. They > were aware that Java isnât the idealistic panacea itâs sometimes made out > to be. Many of them loved to program! Where have you been for the past two > weeks? we thought. > Unfortunately, our ability to attract these developers for the salaries we > were able to pay was limited. They were calling the shots, and most of > them chose to stay where they were or to keep looking for a new job. > Though we failed to recruit many of them, we learned a valuable recruit- > ing lesson: we were more likely to extend offers to candidates with diverse > (and even unorthodox) experience than to those whose experiences were > homogenous. My explanation is that either the good people seek out > diversity, because they love to learn new things, or being forced into alien > experiences and environments created more mature, well-rounded soft- > ware developers. I suspect itâs a little of both, but regardless of why it > works, we learned that it works. I still use this technique when looking > for developers. Nice story, very true here as well, developers with broad interests are better, but there are not many of them. > Laurent Laffont - @lolgzs > > Pharo Smalltalk Screencasts: http://www.pharocasts.com/ > Blog: http://magaloma.blogspot.com/ > Developer group: http://cara74.seasidehosting.st > >

April 9, 2011

Re: [Pharo-project] Have started an independent developer activity - Thank you

by Marcus Denker

On Apr 9, 2011, at 9:34 AM, laurent laffont wrote: > Hi, > > I discovered Smalltalk and Pharo almost three years ago and just after read Chad Fowler book "Passionate Programmer" (1st edition title was "My job went to India"). These have changed my developer life, how I perceive software and that great technology is fun, people doing it more. You're a cool community and I'm proud to be there. > > Now I've started an aside (paid :) independent developer activity thanks to a cool guy. That would not be possible without all the stuff I learn every day from the community and the urge to continue you give me. > > Each time I've made a step forward (open a blog, write ProfStef, fix bugs, create PharoCasts) I've been amazed that the generated effects were those described in Passionate Programmer (go read it !) The last chapter is "Go independent" so now I need the sequel ;) > So we can add an entry to the "companies using pharo" soon, I hope! http://www.pharo-project.org/about/success-stories -- Marcus Denker -- http://www.marcusdenker.de INRIA Lille -- Nord Europe. Team RMoD.

April 9, 2011

Re: [Pharo-project] Have started an independent developer activity - Thank you

by StÃ©phane Ducasse

Tx :) I want more laurent laffont :) Stef On Apr 9, 2011, at 9:34 AM, laurent laffont wrote: > Hi, > > I discovered Smalltalk and Pharo almost three years ago and just after read Chad Fowler book "Passionate Programmer" (1st edition title was "My job went to India"). These have changed my developer life, how I perceive software and that great technology is fun, people doing it more. You're a cool community and I'm proud to be there. > > Now I've started an aside (paid :) independent developer activity thanks to a cool guy. That would not be possible without all the stuff I learn every day from the community and the urge to continue you give me. > > Each time I've made a step forward (open a blog, write ProfStef, fix bugs, create PharoCasts) I've been amazed that the generated effects were those described in Passionate Programmer (go read it !) The last chapter is "Go independent" so now I need the sequel ;) > > Special big thank you to StÃ©phane Ducasse - you're crazy :) Long live Pharo ! > > > PS: nice piece of Passionate Programmer: > > When I was in India weeding through hundreds of candidates for only > tens of jobs, the interview team was exhausting itself and running out > of time because of a poor interview-to-hire hit rate. Heads hurting and > eyes red, we held a late-night meeting to discuss a strategic change in the > way we would go through the candidates. We had to either optimize the > process so we could interview more people or somehow interview better > people (or both). With what little was left of my voice after twelve straight > hours of trying to drag answers out of dumbstruck programmers, I argued > for adding Smalltalk to the list of keywords our headhunters were using > to search their rÃ©sumÃ© database. But, nobody knows Smalltalk in India, cried > the human resources director. That was my point. Nobody knew it, and > programming in Smalltalk was a fundamentally different experience than > programming in Java. The varying experience would give candidates a > different level of expectations, and the dynamic nature of the Smalltalk > environment would reshape the way a Java programmer would approach > a problem. My hope was that these factors would encourage a level of > technical maturity that I hadnât been seeing from the candidates Iâd met so > far. > The addition of Smalltalk to the requirements list yielded a candidate pool > that was tiny in contrast to our previous list. These people were diamonds > in the rough. They really understood object-oriented programming. They > were aware that Java isnât the idealistic panacea itâs sometimes made out > to be. Many of them loved to program! Where have you been for the past two > weeks? we thought. > Unfortunately, our ability to attract these developers for the salaries we > were able to pay was limited. They were calling the shots, and most of > them chose to stay where they were or to keep looking for a new job. > Though we failed to recruit many of them, we learned a valuable recruit- > ing lesson: we were more likely to extend offers to candidates with diverse > (and even unorthodox) experience than to those whose experiences were > homogenous. My explanation is that either the good people seek out > diversity, because they love to learn new things, or being forced into alien > experiences and environments created more mature, well-rounded soft- > ware developers. I suspect itâs a little of both, but regardless of why it > works, we learned that it works. I still use this technique when looking > for developers. > > > Laurent Laffont - @lolgzs > > Pharo Smalltalk Screencasts: http://www.pharocasts.com/ > Blog: http://magaloma.blogspot.com/ > Developer group: http://cara74.seasidehosting.st > >

April 9, 2011

[Pharo-project] Have started an independent developer activity - Thank you

by laurent laffont

Hi, I discovered Smalltalk and Pharo almost three years ago and just after read Chad Fowler book "Passionate Programmer" (1st edition title was "My job went to India"). These have changed my developer life, how I perceive software and that great technology is fun, people doing it more. You're a cool community and I'm proud to be there. Now I've started an aside (paid :) independent developer activity thanks to a cool guy. That would not be possible without all the stuff I learn every day from the community and the urge to continue you give me. Each time I've made a step forward (open a blog, write ProfStef, fix bugs, create PharoCasts) I've been amazed that the generated effects were those described in Passionate Programmer (go read it !) The last chapter is "Go independent" so now I need the sequel ;) Special big thank you to StÃ©phane Ducasse - you're crazy :) Long live Pharo ! PS: nice piece of Passionate Programmer: When I was in India weeding through hundreds of candidates for only tens of jobs, the interview team was exhausting itself and running out of time because of a poor interview-to-hire hit rate. Heads hurting and eyes red, we held a late-night meeting to discuss a strategic change in the way we would go through the candidates. We had to either optimize the process so we could interview more people or somehow interview better people (or both). With what little was left of my voice after twelve straight hours of trying to drag answers out of dumbstruck programmers, I argued for adding Smalltalk to the list of keywords our headhunters were using to search their rÃ©sumÃ© database. But, nobody knows Smalltalk in India, cried the human resources director. That was my point. Nobody knew it, and programming in Smalltalk was a fundamentally different experience than programming in Java. The varying experience would give candidates a different level of expectations, and the dynamic nature of the Smalltalk environment would reshape the way a Java programmer would approach a problem. My hope was that these factors would encourage a level of technical maturity that I hadnât been seeing from the candidates Iâd met so far. The addition of Smalltalk to the requirements list yielded a candidate pool that was tiny in contrast to our previous list. These people were diamonds in the rough. They really understood object-oriented programming. They were aware that Java isnât the idealistic panacea itâs sometimes made out to be. Many of them loved to program! Where have you been for the past two weeks? we thought. Unfortunately, our ability to attract these developers for the salaries we were able to pay was limited. They were calling the shots, and most of them chose to stay where they were or to keep looking for a new job. Though we failed to recruit many of them, we learned a valuable recruit- ing lesson: we were more likely to extend offers to candidates with diverse (and even unorthodox) experience than to those whose experiences were homogenous. My explanation is that either the good people seek out diversity, because they love to learn new things, or being forced into alien experiences and environments created more mature, well-rounded soft- ware developers. I suspect itâs a little of both, but regardless of why it works, we learned that it works. I still use this technique when looking for developers. Laurent Laffont - @lolgzs <http://twitter.com/#!/lolgzs> Pharo Smalltalk Screencasts: http://www.pharocasts.com/ Blog: http://magaloma.blogspot.com/ Developer group: http://cara74.seasidehosting.st

April 9, 2011

Re: [Pharo-project] Unexpected behavior of roundTo:

by Marcus Denker

On Apr 9, 2011, at 9:09 AM, Andres Valloud wrote: > At the end of the day, we still insist on expecting there won't be loss of information just because we wrote a decimal print string for a binary floating point number. One can get offended or irritated all one wants, but the reality of the situation won't change. > > I think the real solution to these "problems" is to implement decimal floating point as per IEEE-754/2008. \\ The MPFR lib seems to me (as far as I understand) is inspired by IEEE 754 <SNIP> MPFR is a portable library written in C for arbitrary precision arithmetic on floating-point numbers. It is based on the GNU MP library. It aims to provide a class of floating-point numbers with precise semantics. The main characteristics of MPFR, which make it differ from most arbitrary precision floating-point software tools, are: â¢ the MPFR code is portable, i.e., the result of any operation does not depend on the machine word size mp_bits_per_limb (64 on most current processors); â¢ the precision in bits can be set exactly to any valid value for each variable (including very small precision); â¢ MPFR provides the four rounding modes from the IEEE 754-1985 standard, plus away-from-zero, as well as for basic operations as for other mathematical functions. .... The following five rounding modes are supported: â¢ MPFR_RNDN: round to nearest (roundTiesToEven in IEEE 754-2008), â¢ MPFR_RNDZ: round toward zero (roundTowardZero in IEEE 754-2008), â¢ MPFR_RNDU: round toward plus infinity (roundTowardPositive in IEEE 754-2008), â¢ MPFR_RNDD: round toward minus infinity (roundTowardNegative in IEEE 754-2008), â¢ MPFR_RNDA: round away from zero (experimental). The âround to nearestâ mode works as in the IEEE 754 standard: in case the number to be rounded lies exactly in the middle of two representable numbers, it is rounded to the one with the least significant bit set to zero. For example, the number 2.5, which is represented by (10.1) in binary, is rounded to (10.0)=2 with a precision of two bits, and not to (11.0)=3. This rule avoids the drift phenomenon mentioned by Knuth in volume 2 of The Art of Computer Programming (Section 4.2.2). </SNIP> > Then you can write something like 1.2345 and know for a fact the number represented is *exactly* 1.2345. At least one VisualWorks platform already supports decimal floating point in hardware (IBM's POWER line). C99 extensions exist at least in draft form to extend C so that it supports decimal floating point. IBM has released a GPL library in ANSI C that implements the feature. I am not sure what is the deal with the license and if you can e.g.: interface to it without making your whole Smalltalk GPL. > MPFR is LGPL, so linking that in the VM or using it via FFI is no problem license wise. Marcus -- Marcus Denker -- http://www.marcusdenker.de INRIA Lille -- Nord Europe. Team RMoD.

April 9, 2011

Re: [Pharo-project] Initial PetitC parser

by StÃ©phane Ducasse

in that case you have also cil in oCaml used by Frama-C. But I do not think that this is necessary to read all the ressources of earth. Javier contact nick because he started (I guess to implement a parser for C using PP). Stef On Apr 8, 2011, at 8:25 PM, Alexandre Bergel wrote: > A good source of ideas: http://www.sdml.info/projects/srcml/ > > Alexandre > > > On 8 Apr 2011, at 12:57, Javier PimÃ¡s wrote: > >> >> >> On Fri, Apr 8, 2011 at 1:08 PM, Alexandre Bergel <alexandre.bergel(a)me.com> wrote: >> What is tricky with analyzing C are macros and preprocessors directive. >> srcML does a satisfactory job. But indeed, having a solution based on PetitParser is indeed promising. >> >> Yes, and I don't know what to do, and would like to know if you or someone else have any idea of how to solve it. I will think some approach, but if you have some idea to share it would be better so I go directly to a good solution. I'm thinking that to feed the parser I'll have to preprocess the string with another parser, and make a string to string conversion by having a set of defines and paths so that #includes and #ifdefs work. But probably I'll need a cache because the generated string will be huge. >> >> What do you think? >> >> Regards, >> Javier. >> >> Cheers, >> Alexandre >> >> >> On 7 Apr 2011, at 23:53, Javier PimÃ¡s wrote: >> >>> by the way, the grammar is based on >>> >>> http://www.quut.com/c/ANSI-C-grammar-l-1998.html >>> >>> and >>> >>> http://www.quut.com/c/ANSI-C-grammar-y.html >>> >>> I'd be very grateful if you contribute to cover the full extent of it! >>> >>> >>> On Fri, Apr 8, 2011 at 12:37 AM, Javier PimÃ¡s <elpochodelagente(a)gmail.com> wrote: >>> Hi, >>> I took some time to start developing a C parser with PetitParser. I used the slides of the smalltalk school, they were pretty useful, and after some hours I have a very basic tokens scanner. The idea of this work is to be able to feed the parser with C headers and automagically get the C bindings done in smalltalk. >>> >>> Now I have to actually start doing something with the scanned code. How should I do that, all in the same class? What if I want to generate bindings for different kinds of FFIs? Other question, how should I handle preprocessing? (now there isn't any kind of preprocessing) >>> >>> You can see the code, download it and commit improvements to the repo at www.squeaksource.com/Bindings >>> >>> Anybody who is interested is welcomed to help in the development! >>> >>> Regards, >>> Javier. >>> >>> -- >>> Javier PimÃ¡s >>> Ciudad de Buenos Aires >>> >>> >>> >>> -- >>> Javier PimÃ¡s >>> Ciudad de Buenos Aires >> >> -- >> _,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;: >> Alexandre Bergel http://www.bergel.eu >> ^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;. >> >> >> >> >> >> >> >> >> >> -- >> Javier PimÃ¡s >> Ciudad de Buenos Aires > > -- > _,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;: > Alexandre Bergel http://www.bergel.eu > ^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;. > > > > > >

April 9, 2011

Re: [Pharo-project] Unexpected behavior of roundTo:

by Andres Valloud

At the end of the day, we still insist on expecting there won't be loss of information just because we wrote a decimal print string for a binary floating point number. One can get offended or irritated all one wants, but the reality of the situation won't change. I think the real solution to these "problems" is to implement decimal floating point as per IEEE-754/2008. Then you can write something like 1.2345 and know for a fact the number represented is *exactly* 1.2345. At least one VisualWorks platform already supports decimal floating point in hardware (IBM's POWER line). C99 extensions exist at least in draft form to extend C so that it supports decimal floating point. IBM has released a GPL library in ANSI C that implements the feature. I am not sure what is the deal with the license and if you can e.g.: interface to it without making your whole Smalltalk GPL. Food for thought... On 4/8/11 12:53 , Marcus Denker wrote: > > On Apr 8, 2011, at 7:48 PM, Hilaire Fernandes wrote: > >> Well, whatever the underneath representation, one can expect roundedTo: >> 2 to return a float with two decimals. >> > Sometimes I think we should use the resources that these amazing machines > give us these days to move programming languages closer to humans... > > There are better Float models than the ones that are implemented in hardware. > E.g. another INRIA Project is this GNU MPFR: > > "The MPFR library is a C library for multiple-precision floating-point computations with correct rounding." > > http://www.mpfr.org/ > > Why don't we make our language better at "real" math? The power in the machine is definitly there... > I am quite convincd that if there are normal programming languages in 50 years, the math part of them > will be closer to Mathematica then to C... > > Marcus > > > > > > -- > Marcus Denker -- http://www.marcusdenker.de > INRIA Lille -- Nord Europe. Team RMoD. > > >

April 9, 2011

Re: [Pharo-project] Unexpected behavior of roundTo:

by StÃ©phane Ducasse

>> > I played with my own modest Smalltalk implementation relying on > LargeInteger arithmetic > http://www.squeaksource.com/ArbitraryPrecisionFl.html > It implements correct rounding to (if correct is round to nearest even). Nicolas would it be a path for you and us so that we use your library? Ok it will put pressure on you but like that we move one the next age. Stef

April 9, 2011

Re: [Pharo-project] Unexpected behavior of roundTo:

by StÃ©phane Ducasse

Nicolas would not you like the write (I can help) a two three 5 pages document for the next book on this topics? :) I would be gorgeous and everybody would love that Stef On Apr 8, 2011, at 7:18 PM, Nicolas Cellier wrote: > Yes nice example to exhibit in school > > This again happens even if performed exactly (then rounded to nearest Float) > (2.8 asTrueFraction roundTo: 0.01 asTrueFraction) asFloat > > As soon as you write 0.01 instead of (1/100) or (0.01s2), the worm is > in the fruit. > > Nicolas > > 2011/4/8 Hilaire Fernandes <hilaire.fernandes(a)gmail.com>: >> Even better: >> >> 2.8 truncateTo: 0.01 >> -> 2.8000000000000003 >> >> >> Le 08/04/2011 18:52, Hilaire Fernandes a Ã©crit : >>> It looks like a known issue: >>> >>> printShowingDecimalPlaces: placesDesired >>> "This implementation avoids any rounding error caused by rounded or >>> roundTo: " >>> ^ self asTrueFraction printShowingDecimalPlaces: placesDesired >>> >>> >>> >>> Le 08/04/2011 18:47, Hilaire Fernandes a Ã©crit : >>>> 2.8011416510246336 roundTo: 0.01 >>>> >>>> returns >>>> >>>> 2.8000000000000003 >>>> >>>> >>>> Tested with 1.2 >>>> >>>> >>>> Should I fill a ticket, I don't see anythings similar? >>>> >>>> Hilaire >>>> >>> >>> >> >> >> -- >> Education 0.2 -- http://blog.ofset.org/hilaire >> >> >> >

April 9, 2011