October 2013 - Pharo-dev - lists.pharo.org

Re: [Pharo-dev] [Fuel] How to tell Fuel *not* to encode references?

by roberto.minelli＠usi.ch

Iâll look at the docâ¦ However if some of you is online in Skype we can have a chatâ¦ Cheers and thanks for help, Roby On Oct 28, 2013, at 11:45 PM, Mariano Martinez Peck <marianopeck(a)gmail.com> wrote: > Indeed, I think I agree with Max. You can also use the substitute feature and replace the instVars you don't want with nil or something...See the doc link Martin sent. > > > On Mon, Oct 28, 2013 at 7:00 PM, Max Leske <maxleske(a)gmail.com> wrote: > In my opinion the #fuelAccept: for the meta description object should be overridden and there the behaviour for problematic references should be defined. > > Roberto, what references does your meta object hold on to? > > Max > > > On 28.10.2013, at 22:16, Martin Dias <tinchodias(a)gmail.com> wrote: > >> >> >> >> On Mon, Oct 28, 2013 at 5:13 PM, roberto.minelli(a)usi.ch <roberto.minelli(a)usi.ch> wrote: >> The idea is that I have an object (a session) which has meta data (time, duration, author) and some other object inside. >> >> I want that Fuel serializes just that object and not pointes to other object, globals and what not. >> >> This causes me a lot of troubles, moreover it makes the fuel file bigger than the optimumâ¦ >> >> Still there is something that I don't understand in your problem. If you just prune the graph, what your objects represent (conceptually) can be lost. Did you pick one of your problematic "session objects" are explored it until find how the unwanted block closures are referenced? I mean, fuel doesn't invent the unwanted closures magically, you are saying to fuel to serialize the graph with the unwanted objects already there. >> >> >> Cheers, >> R >> >> >> On Oct 28, 2013, at 4:57 PM, Martin Dias <tinchodias(a)gmail.com> wrote: >> >> > >> > >> > >> > On Mon, Oct 28, 2013 at 4:47 PM, roberto.minelli(a)usi.ch <roberto.minelli(a)usi.ch> wrote: >> > Thanks, >> > >> > On Oct 28, 2013, at 4:36 PM, Martin Dias <tinchodias(a)gmail.com> wrote: >> > >> > > Currently there is no such option. >> > >> > Maybe it is something which is needed, what do you think? >> > >> > The idea is that, if you serialize: >> > >> > a -> b -> c >> > >> > fuel actually would encode: >> > >> > a -> b -> nil >> > >> > >> > that? >> > >> > >> >> >> > > > > > -- > Mariano > http://marianopeck.wordpress.com

Oct. 29, 2013

Re: [Pharo-dev] Are there still halos in Pharo 3.0?

by ClÃ©ment Bera

Well I use them all the time. I press shift then while shift is still pressed I select an area and all morphics inside are trapped in the halo. Very useful to delete multiple morphics at once. 2013/10/29 Nicolas Cellier <nicolas.cellier.aka.nice(a)gmail.com> > Thanks Esteban, > It works perfectly. > I would have sweared I've tried this combination... > > > 2013/10/29 Esteban Lorenzano <estebanlm(a)gmail.com> > >> yes. >> alt+shift works for me (in osx) >> >> On Oct 28, 2013, at 9:11 PM, Nicolas Cellier < >> nicolas.cellier.aka.nice(a)gmail.com> wrote: >> >> > I tried various key combinations with mouse click but no one worked... >> > >> > in Morph>>handleMouseDown: >> > it seems like this block never fires: >> > anEvent blueButtonChanged ifTrue:[^self blueButtonDown: anEvent]. >> > >> > Is it still possible to have these halos? >> >> >> >

Oct. 29, 2013

Re: [Pharo-dev] Tests with multiple processes

by David T. Lewis

I have some experience with this, not related to Smalltalk but maybe still relevant. I have worked with systems that were designed around networked message passing, implemented on platforms like MS-DOS with time slicing kernels, Series I, OS/2, etc. These systems were designed to operate with asynchronous message passing protocols. The asynchronous designs were intended to support primitive OS environments, including MS-DOS with software interrupts for multitasking. These are production-critical manufacturing applications, and in the course of modernizing them I have reimplemented the network protocols in Java and moved them to new computing platforms. Along the way I have found that the asynchronous designs could always be replaced by bidirectional send-receive transactions running in the context of a thread or process. Even the systems that appeared to be most complex have turned out to work perfectly well when modeled as synchronous send-receive transactions on a bidirectional communication channel. The software is much simpler to understand and debug when structured in this manner. My conclusion is that designing around asynchronous, loosely coupled channels sounds like a good idea, but in practice it leads to unnecessary complexity, and to systems that are difficult to debug and support. $0.02 Dave On Tue, Oct 29, 2013 at 01:19:17AM +0100, Igor Stasenko wrote: > Maybe i'm off track, but here my thoughts: > > - one big misconception (and most problems which arising from it), that > people tend to use a bidirectional communication models instead of > unidirectional. > In bidirectional you tend to think as if you using same channel for sending > and receiving data. > The truth is, that it is two unidirectional channels, wired in the way so > they look like single bidirectional channel. > > And what it means, that coupling sending and receiving activities in a > single thread is wrong: > - you should not wait for data only if you sent something > - you should not expect that activity from other end is possible only > after you _send_ something. > > If you treat connection as two unidirectional, loosely coupled channels, > instead of single bidirectional one, > you will find that in such setup you don't have many problems. > > You should definitely go for (2), e.g. you should decouple a > transport/communication layer > from your program/logic flow: if some process wants to send data and block > until some response to > that message arrived, you should do so. > You can simply put that process on semaphore, and adding it to the list of > 'awaiting answer' > processes in your scheduler which runs in separate process to handle > incoming data. > Then you can have different strategies, what to do if > a) data seems taking too long to arrive (signal timeout) > b) connection lost > c) etc.. > > ohh.. with smalltalk it is so easy to operate with those things (the fact > the VM is green-threaded doesn't > changes much). > > > > On 28 October 2013 23:52, Norbert Hartl <norbert(a)hartl.name> wrote: > > > > > Am 28.10.2013 um 23:50 schrieb Norbert Hartl <norbert(a)hartl.name>: > > > > Are there any approaches to simulate coroutines in a single thread > > environment or approaches to deal with multiple processes within one > > process? > > > > > > That should have been > > > > Are there any approaches to simulate coroutines in a single thread > > environment or approaches to deal with multiple processes within one test? > > > > Norbert > > > > > > -- > Best regards, > Igor Stasenko.

Oct. 29, 2013

Re: [Pharo-dev] Are there still halos in Pharo 3.0?

by Nicolas Cellier

Thanks Esteban, It works perfectly. I would have sweared I've tried this combination... 2013/10/29 Esteban Lorenzano <estebanlm(a)gmail.com> > yes. > alt+shift works for me (in osx) > > On Oct 28, 2013, at 9:11 PM, Nicolas Cellier < > nicolas.cellier.aka.nice(a)gmail.com> wrote: > > > I tried various key combinations with mouse click but no one worked... > > > > in Morph>>handleMouseDown: > > it seems like this block never fires: > > anEvent blueButtonChanged ifTrue:[^self blueButtonDown: anEvent]. > > > > Is it still possible to have these halos? > > >

Oct. 29, 2013

Re: [Pharo-dev] Tests with multiple processes

by Igor Stasenko

Maybe i'm off track, but here my thoughts: - one big misconception (and most problems which arising from it), that people tend to use a bidirectional communication models instead of unidirectional. In bidirectional you tend to think as if you using same channel for sending and receiving data. The truth is, that it is two unidirectional channels, wired in the way so they look like single bidirectional channel. And what it means, that coupling sending and receiving activities in a single thread is wrong: - you should not wait for data only if you sent something - you should not expect that activity from other end is possible only after you _send_ something. If you treat connection as two unidirectional, loosely coupled channels, instead of single bidirectional one, you will find that in such setup you don't have many problems. You should definitely go for (2), e.g. you should decouple a transport/communication layer from your program/logic flow: if some process wants to send data and block until some response to that message arrived, you should do so. You can simply put that process on semaphore, and adding it to the list of 'awaiting answer' processes in your scheduler which runs in separate process to handle incoming data. Then you can have different strategies, what to do if a) data seems taking too long to arrive (signal timeout) b) connection lost c) etc.. ohh.. with smalltalk it is so easy to operate with those things (the fact the VM is green-threaded doesn't changes much). On 28 October 2013 23:52, Norbert Hartl <norbert(a)hartl.name> wrote: > > Am 28.10.2013 um 23:50 schrieb Norbert Hartl <norbert(a)hartl.name>: > > Are there any approaches to simulate coroutines in a single thread > environment or approaches to deal with multiple processes within one > process? > > > That should have been > > Are there any approaches to simulate coroutines in a single thread > environment or approaches to deal with multiple processes within one test? > > Norbert > -- Best regards, Igor Stasenko.

Oct. 29, 2013

Re: [Pharo-dev] Are there still halos in Pharo 3.0?

by Esteban Lorenzano

yes. alt+shift works for me (in osx) On Oct 28, 2013, at 9:11 PM, Nicolas Cellier <nicolas.cellier.aka.nice(a)gmail.com> wrote: > I tried various key combinations with mouse click but no one worked... > > in Morph>>handleMouseDown: > it seems like this block never fires: > anEvent blueButtonChanged ifTrue:[^self blueButtonDown: anEvent]. > > Is it still possible to have these halos?

Oct. 29, 2013

Are there still halos in Pharo 3.0?

by Nicolas Cellier

I tried various key combinations with mouse click but no one worked... in Morph>>handleMouseDown: it seems like this block never fires: anEvent blueButtonChanged ifTrue:[^self blueButtonDown: anEvent]. Is it still possible to have these halos?

Oct. 29, 2013

Re: [Pharo-dev] Tests with multiple processes

by Sebastian Sastre

you can do stuff like that, just not sync (which when it's about networks is a good idea) sounds like you should design things javascript style. I mean, like if "everything" is a callback reacting to something.. yourAPIClient sendCommand: aCommand do: aBlockHandlingResponse my 2 cents On Oct 28, 2013, at 8:50 PM, Norbert Hartl <norbert(a)hartl.name> wrote: > Iâm working on project that deals with server to server communication. For the test suite it is necessary to simulate the two ends of the communication within one test. The problem is that in a single threaded environment you make a send call SC from server A to B but the response of B will happen before SC returned. That makes every state change the happens in A after SC bogus from a call flow perspective. > > There are two approaches that have their own problems. > > 1) Until now Iâm reordering parts of the call stack to simulate the return of a call before the actual call is sent. But now I have nested sends that make my simple approach not working anymore. I could elaborate my approach by using something like delimited continuations to make a less brittle approach to stack call reordering in order to cope with the problem. That would need some work and the stack in the debugger will look a little bit odd/confusing. > > 2.) The product will later have a dispatcher process that dispatches each send operation in its own process. That would solve one problem: the timing of when actions happen. But Iâm not sure if it will be easy to orchestrate actions in a way that I would call controlled in order to have reliable tests. > > Are there any approaches to simulate coroutines in a single thread environment or approaches to deal with multiple processes within one process? > > It is hard to explain and I hope my description of the problem is understandable > > thanks in advance, > > Norbert

Oct. 29, 2013

Re: [Pharo-dev] Tests with multiple processes

by Norbert Hartl

Am 28.10.2013 um 23:50 schrieb Norbert Hartl <norbert(a)hartl.name>: > Are there any approaches to simulate coroutines in a single thread environment or approaches to deal with multiple processes within one process? That should have been Are there any approaches to simulate coroutines in a single thread environment or approaches to deal with multiple processes within one test? Norbert

Oct. 28, 2013

Tests with multiple processes

by Norbert Hartl

Iâm working on project that deals with server to server communication. For the test suite it is necessary to simulate the two ends of the communication within one test. The problem is that in a single threaded environment you make a send call SC from server A to B but the response of B will happen before SC returned. That makes every state change the happens in A after SC bogus from a call flow perspective. There are two approaches that have their own problems. 1) Until now Iâm reordering parts of the call stack to simulate the return of a call before the actual call is sent. But now I have nested sends that make my simple approach not working anymore. I could elaborate my approach by using something like delimited continuations to make a less brittle approach to stack call reordering in order to cope with the problem. That would need some work and the stack in the debugger will look a little bit odd/confusing. 2.) The product will later have a dispatcher process that dispatches each send operation in its own process. That would solve one problem: the timing of when actions happen. But Iâm not sure if it will be easy to orchestrate actions in a way that I would call controlled in order to have reliable tests. Are there any approaches to simulate coroutines in a single thread environment or approaches to deal with multiple processes within one process? It is hard to explain and I hope my description of the problem is understandable thanks in advance, Norbert

Oct. 28, 2013