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[Pharo-project] Beginner question about "self" in block
by Garret Raziel Jan. 28, 2012

Jan. 28, 2012

Hi, I have one begginer question. It is may be simple, but it very baffles me. I am reading Pharo by Example (great book btw, thanks!). I'm in chapter two where I'm creating Lights Out game. There is this simple code http://pastebin.com/eQregZ35. What baffles me is line 10. I assign "Block of code" to mouseAction variable of LOCell. In this Block, there is "self", that obviously refers to LOGame object in that time. But when is this Block actualy EVALUATED (when I click on Cell), "self" should be reffering to LOCell object, isn't it? If I inspect one LOCell, inspector shows that it has instance variable "mouseAction", which is BlockClosure, that looks like "[self toggleNeighboursOfCellAt: i at: j]". If "LOCell" is the "owner" of this block and also it is the one that evaluates it, shouldn't "self" refer to LOCell object? How BlockClosure desides where "self" actually points? Thanks for explanation. Jan

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[Pharo-project] Customizing Explore
by Ben Coman Jan. 28, 2012

Jan. 28, 2012

I want to customize the Explorer that comes up when you press <shift><alt><i> such that as well as browsing my model, I can have a custom menu on each displayed class to instantiate one of the relationships defined on that class. For example, if the Explorer shows a Library object, then right-clicking on that object will bring up a menu with item "Add book". What are the classes I should be looking at for examples? cheers, Ben

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Re: [Pharo-project] Beginner question about "self" in block
by Marcus Denker Jan. 27, 2012

Jan. 27, 2012

On Jan 27, 2012, at 3:26 PM, Ben Coman wrote: > StÃ©phane Ducasse wrote: >> I guess that in naked objects book they discussed some patterns for relationships. >> What I would love to have is first class slots so that we can easily express relationships like the ones you describe. >> But I have too busy. >> I'm rereading the paper of toon, camillo et all to see what we could reasonably do. >> For those who want to read it: http://rmod.lille.inria.fr/web/pier/publications/bib?&query=Verw11a&display… Toon Verwaest, Camillo Bruni, Mircea Lungu, and Oscar Nierstrasz. Flexible object layouts: enabling lightweight language extensions by intercepting slot access. In Proceedings of OOPSLA '11 Abstract --------- Programming idioms, design patterns and application libraries often introduce cumbersome and repetitive boilerplate code to a software system. Language extensions and external DSLs (domain specific languages) are sometimes introduced to reduce the need for boilerplate code, but they also complicate the system by introducing the need for language dialects and inter-language mediation. To address this, we propose to extend the structural reflective model of the language with object layouts, layout scopes and slots. Based on the new reflective language model we can 1) provide behavioral hooks to object layouts that are triggered when the fields of an object are accessed and 2) simplify the implementation of state-related language extensions such as stateful traits. By doing this we show how many idiomatic use cases that normally require boilerplate code can be more effectively supported. We present an implementation in Smalltalk, and illustrate its usage through a series of extended examples. -- Marcus Denker -- http://marcusdenker.de

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[Pharo-project] cogwin/Croquet (Win7) + Moose + very large models = crash (out of Memory)
by Hani Abdeen Jan. 27, 2012

Jan. 27, 2012

Hello, I'm using cogwin/Croquet VM (last version http://www.mirandabanda.org/files/Cog/VM/VM.r2522/) on windows7, and today I had this probelm: when the size of the pharo image become so large the VM crashes with reason 'out of memory'. The same problem with previous versions of cogwin. Note that I use a PC with 8G of RAM, so it's really damage to have such a problem. Any idea about another VM working well on Windows and does not have such an issues? Any urgent solution? Thanks, Hani

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[Pharo-project] Proposed (or just written down desired) Keyboard Event Model
by Guillermo Polito Jan. 27, 2012

Jan. 27, 2012

Following the Event chronicles :P Since I know that some people are working on event Stuff(Stef, Fernando, Igor), I'd like to listen to what they(or anybody else :) ) think about this. I've no code (yet) except for the one I've written to play with the vm and test the keyboard stuff :P. And I know there is some package where Stef and Igor where refactoring the event stuff and I don't want to duplicate efforts either, jeje. So, this is what from other models I think a complete keyboard event model should have: Keyboard interaction raises 3 events (3 different kind of objects!): - Keydown When a key is pressed, it informs the pressed key with modifiers (it should not send a unicode value of a character). Should understand the messages: "boolean indicating which modifiers where pressed" #alt #cmd #shift #ctrl #opt? "a collection of modifier objects" #modifiers "the key pressed. It is not a Character, it should be an instance of Key (read about Keys in the Glitches below)" #key "to know if the event wasHandled" #handled: #handled - Keypress When a key with a unicode representation is pressed, informs it. should understand the messages: "the unicode character representation of this event. It is a Character, not an instance of Key" #character "to know if the event wasHandled" #handled: #handled - Keyup When a key is released, it informs the released key with modifiers (it should not send a unicode value of a character). Should understand the messages: "the main key pressed. It is not a Character, it should be an instance of Key (read about Keys in the Glitches below)" #key "to know if the event wasHandled" #handled: #handled =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= *Glitches* 1) Today every keyboard event handled on the image side is handled on keypress, which: - limits the ammount of shortcuts you can have (because there are keys that you can't handle) - to make it work, there are some hacks (at image and vm side) to allow keys with no char representation enter as keypresses (like arrow keys). - changing this is ALOT of work :P 2) Some key representation varies from platform to platform. i.e.: A Shift-only press generates today a keydown event with: - a 254 keyCode value in unix - a 16 keyCode value in windows So I think a "table" has to be built and documented for mappings for each key in a keyboard. Examples of this can be found in enums/defs from other platforms: Windows platform: http://msdn.microsoft.com/en-us/library/windows/desktop/dd375731(v=vs.85).a… .Net: http://msdn.microsoft.com/en-us/library/system.windows.forms.keys(v=vs.71).… X11 (current used window system in unix vm): http://cgit.freedesktop.org/xorg/proto/x11proto/plain/keysymdef.h Javascript: http://www.cambiaresearch.com/articles/15/javascript-char-codes-key-codes Gtk: http://www.koders.com/c/fidD9E5E78FD91FE6ABDD6D3F78DA5E4A0FADE79933.aspx After that, both vm's and image should follow that table :). And of course, these keys should be reified in the image side independently of their character pairs. Guille

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[Pharo-project] This is so cool, and we can compute it !
by Sven Van Caekenberghe Jan. 27, 2012

Jan. 27, 2012

This is so cool, and we can compute it using Pharo Smalltalk. Try inspecting or printing the result of these expressions: 1/9801 asScaledDecimal: 200 1/998001 asScaledDecimal: 3000 And have a good look at the regularity in the digits of the fraction. Amazing ! Sven

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[Pharo-project] Pharo sprint in Brussels on Feb 4th
by Andy Kellens Jan. 27, 2012

Jan. 27, 2012

Dear Pharoers, In an earlier mail Stephan Eggermont already mentioned that there will be Pharo sprint collocated with the FOSDEM conference next week. This sprint will take place on Saturday February 4th from 10h until 18h in the rooms of the Software Languages Lab of the Vrije Universiteit Brussel. More precisely: Room 10F720 (10th floor of building F) Vrije Universiteit Brussel Pleinlaan 2 1050 Brussels Due to renovations to our building, you will have to enter via the entrance between buildings F and G. As the university is normally closed on a Saturday, you might have to pass via security in order to be allowed entrance to the building (they have been notified about the sprint). If you are coming by car, please send me your license plate so that I can make sure that you are allowed to enter the campus. To get some idea of how many people to expect, could you please let us know if you are planning to attend. Kind regards, Andy

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[Pharo-project] Enthousiasm is the main currency among developers
by Sven Van Caekenberghe Jan. 27, 2012

Jan. 27, 2012

The following 10 year old Usenet article is quite interesting: http://groups.google.com/group/comp.lang.lisp/msg/4563e504dba92253 Although it is quite long and partly about Common Lisp, its main point is that enthousiasm and positive energy are the main/natural currency among developers. I think that this is also the main driving force behind Pharo. The author is Erik Naggum (http://en.wikipedia.org/wiki/Erik_Naggum) a programmer and (in)famous, provocative participant to many discussions. He died a couple of years ago. Sven

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Re: [Pharo-project] Enthousiasm is the main currency among developers
by Fernando Olivero Jan. 27, 2012

Jan. 27, 2012

Gerald Weinberg accurately describes us in this book titled: The Psychology Of Computer Programming, published in 1971. He talked about Ego-less programming[2], which nowadays empowers open source projects. [1] http://www.amazon.com/Psychology-Computer-Programming-Silver-Anniversary/dp… [2] http://c2.com/cgi/wiki?EgolessProgramming On Fri, Jan 27, 2012 at 10:12 AM, dimitris chloupis <thekilon(a)yahoo.co.uk> wrote: > This article is really encapsulates the attitude and what is wrong with programming in general. The attitude of superiority and intelligence that seems to plague coders and being the biggest obstacle to progress. And what biggest proof of lack of progress than the fact that Lips is probably the very best that programming languages have to offer. 40 year old technology, how sad that is ? Actually if there is one thing thats driving the coding community is lack of enthusiasm, is about sticking to what is already there , is the fact of being "practical" and "realistic" about code in general. How much progress we have seen the last 40 years ? Sure its alot , but what happens if you take games out of it , how much hardware would have progress ? How much software ? Very little. > > If you take out games that exercise a clear push to graphics and processing power and complex data manipulation approaches , AI and many other things , the rest of software out there , if you remove some exceptions here and there, is the same boring stuff which makes you wait for a year to add a single feature you need with a dozen more you don't need. > > Its not enthusiasm that drives coding, its money and profit. > > Then we arrive at the open source phenomenon, which I agree its great and amazing and where exciting stuff really happens. But even open has some major issue to resolve. First is to anyone surprise is that all that open source is rarely used and recycled, most open source projects seem to start from scratch , rarely using source from other projects. And then of course there is the big issue of licence , its open source, but its not really open ... GPL as an example of Â a licence driving open source back instead of forward. > > For me the main problem with is the whole aura of Â "elitism" , what better example than Lisp, where beginners are attacked and be excluded. It took me 4 years to really get into Lisp after hearing about because of all the bad attitude. Its the whole motivation to prove that coding is for "smart people" and not "normal" people as he mentions in his article. There is something "mysteriously" superior about coders .... The only thing I find "mysterious" about coders is that they think they are "superior" or somewhat special. They are not. > > And if we can really kick all that non sense outside coding, if we can make coding for "stupid" , "normal" people and open source project non "VIP Clubs" , if we really make coding inviting for people then maybe just maybe we will see open source that instead of 10 developers and 1 million user will have 1 million developer that are also users. > > Of course in the end what is wrong with the coding community is not detached with what is wrong with the world and human attitude in general. > > Saying that I am not saying there not some amazing projects out there and some great people, but I really cant share his enthusiasm and optimism. > > PS : he seems to complain a lot about the forks of Lisp. Is it not Lisp a factory of programming languages ? I agree with him that those should not be called Common Lisp if they do not conform but I disagree that their existence is a bad thing. You cant go forward if you dont reinvent the wheel. Even though "reinventing" seems to be a forbidden word in coding. > > ________________________________ > From: Sven Van Caekenberghe <sven(a)beta9.be> > To: "Pharo-project(a)lists.gforge.inria.fr Development" <Pharo-project(a)lists.gforge.inria.fr> > Sent: Friday, 27 January 2012, 10:18 > Subject: [Pharo-project] Enthousiasm is the main currency among developers > > The following 10 year old Usenet article is quite interesting: > > Â http://groups.google.com/group/comp.lang.lisp/msg/4563e504dba92253 > > Although it is quite long and partly about Common Lisp, its main point is that enthousiasm and positive energy are the main/natural currency among developers. I think that this is also the main driving force behind Pharo. > > The author is Erik Naggum (http://en.wikipedia.org/wiki/Erik_Naggum) a programmer and (in)famous, provocative participant to many discussions. He died a couple of years ago. > > Sven > >

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[Pharo-project] Written down current Keyboard Event Model
by Guillermo Polito Jan. 27, 2012

Jan. 27, 2012

Maybe this has to be written in the wiki, the book, or something :P. Keyboard interaction raises 3 events: - Keydown When a key is pressed, it informs the same as a keystroke. *Nobody uses it :/.* Also, between platforms, the keydown events are different Â¬Â¬. Even more!! These events are not taken into account by morphic EventHandler :D. Just try: aMorph on: #keyDown send: #value to: [ UIManager inform: 'hello!'] - Keyup When a key is released, it informs the same as a keystroke. *Nobody uses it :/.* Also, between platforms, the keyup events are different Â¬Â¬. Even more!! Those events are not taken into account in morphic EventHandler :D. Just try: aMorph on: #keyUp send: #value to: [ UIManager inform: 'hello!'] - Keypress When a key with a unicode representation is pressed, informs: -modifiers. Hey guess what? If you type ctrl+a character, you'll get cmd+that character. Be careful ;). -keyCode: a value representing the key pressed (not the character equivalent) -keyCharacter: a character representing the key pressed. It may not be a printable character, so, be careful ;). to subscribe a morph to this event just do: Even more!! They are not took into account in morphic EventHandler :D. Just try: aMorph on: #keyStroke send: #value to: [ UIManager inform: 'hello!' ]. Guille, messing with events and stuff, and vms, and bored :P

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