- Pharo-users - lists.pharo.org

Re: [Pharo-users] Trait composition on runtime

by Johan Fabry

Define 'widely used' and 'is it necessary' ;-) I would say, from the point of view of an Aspects guy (me), that a noticeable influence in the acceptance of the language AspectJ is that they have an acceptable level of IDE support. And there is no escaping the fact that sometimes the decomposition of the system will lead to code that is scattered around different places. Single inheritance with objects is not a silver bullet. But it can be 'good enough' â¦ worse is better ... On Aug 22, 2013, at 4:25 PM, Juraj Kubelka <juraj.kubelka(a)gmail.com> wrote: > Is there any "more complex" system which is widely used? I am interested if it has a sense to spend time on researching something better than single-inheritance OOP, traits, etc. Because "Worse is Better" is maybe the point. > > For example I found easier to improve (optimize) an existing application structure by using traits/aspects/etc. But for a new parts of system it looks easier to think in single-inheritance-objects. About optimisation developers think when it is necessary. Is it? > > Cheers, > Jura > > El 22-08-2013, a las 16:11, Johan Fabry <jfabry(a)dcc.uchile.cl> escribiÃ³: > >> >> I think that indeed you touch on 2 important cultural issues, first the entire "Worse is Better" discussion (started by Richard Gabriel), and second that IDE support is key for getting more advanced forms of modularity in use. In my experience, sadly, Traits support in Pharo has been less than ideal. In 2.0 it has improved though, so I am happy about that. >> >> On Aug 22, 2013, at 4:03 PM, Juraj Kubelka <juraj.kubelka(a)gmail.com> wrote: >> >>> Interesting. Is it only problem of system complexity? I have the impression the problem is that people do not changed his mind in order to think in traits. (or generally speaking in any other system like mixins, aspects, etc.) It looks like objects with single-inheritance are simple and powerful enough. >>> >>> Or maybe any system like traits have not come with efficient enough IDE? >> >> >> >> ---> Save our in-boxes! http://emailcharter.org <--- >> >> Johan Fabry - http://pleiad.cl/~jfabry >> PLEIAD lab - Computer Science Department (DCC) - University of Chile >> >> > ---> Save our in-boxes! http://emailcharter.org <--- Johan Fabry - http://pleiad.cl/~jfabry PLEIAD lab - Computer Science Department (DCC) - University of Chile

Aug. 22, 2013

Re: [Pharo-users] Trait composition on runtime

by Juraj Kubelka

Is there any "more complex" system which is widely used? I am interested if it has a sense to spend time on researching something better than single-inheritance OOP, traits, etc. Because "Worse is Better" is maybe the point. For example I found easier to improve (optimize) an existing application structure by using traits/aspects/etc. But for a new parts of system it looks easier to think in single-inheritance-objects. About optimisation developers think when it is necessary. Is it? Cheers, Jura El 22-08-2013, a las 16:11, Johan Fabry <jfabry(a)dcc.uchile.cl> escribiÃ³: > > I think that indeed you touch on 2 important cultural issues, first the entire "Worse is Better" discussion (started by Richard Gabriel), and second that IDE support is key for getting more advanced forms of modularity in use. In my experience, sadly, Traits support in Pharo has been less than ideal. In 2.0 it has improved though, so I am happy about that. > > On Aug 22, 2013, at 4:03 PM, Juraj Kubelka <juraj.kubelka(a)gmail.com> wrote: > >> Interesting. Is it only problem of system complexity? I have the impression the problem is that people do not changed his mind in order to think in traits. (or generally speaking in any other system like mixins, aspects, etc.) It looks like objects with single-inheritance are simple and powerful enough. >> >> Or maybe any system like traits have not come with efficient enough IDE? > > > > ---> Save our in-boxes! http://emailcharter.org <--- > > Johan Fabry - http://pleiad.cl/~jfabry > PLEIAD lab - Computer Science Department (DCC) - University of Chile > >

Aug. 22, 2013

Re: [Pharo-users] Trait composition on runtime

by Johan Fabry

I think that indeed you touch on 2 important cultural issues, first the entire "Worse is Better" discussion (started by Richard Gabriel), and second that IDE support is key for getting more advanced forms of modularity in use. In my experience, sadly, Traits support in Pharo has been less than ideal. In 2.0 it has improved though, so I am happy about that. On Aug 22, 2013, at 4:03 PM, Juraj Kubelka <juraj.kubelka(a)gmail.com> wrote: > Interesting. Is it only problem of system complexity? I have the impression the problem is that people do not changed his mind in order to think in traits. (or generally speaking in any other system like mixins, aspects, etc.) It looks like objects with single-inheritance are simple and powerful enough. > > Or maybe any system like traits have not come with efficient enough IDE? ---> Save our in-boxes! http://emailcharter.org <--- Johan Fabry - http://pleiad.cl/~jfabry PLEIAD lab - Computer Science Department (DCC) - University of Chile

Aug. 22, 2013

Re: [Pharo-users] Trait composition on runtime

by Juraj Kubelka

El 22-08-2013, a las 14:12, StÃ©phane Ducasse <stephane.ducasse(a)inria.fr> escribiÃ³: >>> >>>> Does pharo support runtime trait composition or does it only work on class definition time. I mean something like >>>> >>>> anObject addTrait: MySpecialCapability >>>> anObject removeTrait: MySpecialCapability >>> >>> Nope :) >>> traits are static :) >> >> Sad. You know I was not asking about trait but about runtime composable behavior. I'm not sure what you mean with "traits are static". If traits are static in pharo that's fine. If you think traits are static by design then I was looking for something that has a different name :) > > :) > > What I think is that traits are cool but not powerful enough but even the ones that we have right now > makes the system more complex and this is what makes me sad :) I would prefer something more powerful > and simpler: the graal :) > > Stef Interesting. Is it only problem of system complexity? I have the impression the problem is that people do not changed his mind in order to think in traits. (or generally speaking in any other system like mixins, aspects, etc.) It looks like objects with single-inheritance are simple and powerful enough. Or maybe any system like traits have not come with efficient enough IDE? Cheers, Jura

Aug. 22, 2013

Re: [Pharo-users] Trait composition on runtime

by Johan Fabry

Norbert, do you want to be able to programmatically add and remove traits at runtime? I wrote a small utility for that a while ago that still works OK (All tests are still green in 2.0). See http://www.squeaksource.com/TraitsApplication.html Hope this helps. On Aug 22, 2013, at 1:19 PM, Norbert Hartl <norbert(a)hartl.name> wrote: > > Sad. You know I was not asking about trait but about runtime composable behavior. I'm not sure what you mean with "traits are static". If traits are static in pharo that's fine. If you think traits are static by design then I was looking for something that has a different name :) ---> Save our in-boxes! http://emailcharter.org <--- Johan Fabry - http://pleiad.cl/~jfabry PLEIAD lab - Computer Science Department (DCC) - University of Chile

Aug. 22, 2013

Re: [Pharo-users] Trait composition on runtime

by StÃ©phane Ducasse

>> >>> Does pharo support runtime trait composition or does it only work on class definition time. I mean something like >>> >>> anObject addTrait: MySpecialCapability >>> anObject removeTrait: MySpecialCapability >> >> Nope :) >> traits are static :) > > Sad. You know I was not asking about trait but about runtime composable behavior. I'm not sure what you mean with "traits are static". If traits are static in pharo that's fine. If you think traits are static by design then I was looking for something that has a different name :) :) What I think is that traits are cool but not powerful enough but even the ones that we have right now makes the system more complex and this is what makes me sad :) I would prefer something more powerful and simpler: the graal :) Stef

Aug. 22, 2013

Re: [Pharo-users] Trait composition on runtime

by Norbert Hartl

Am 22.08.2013 um 16:25 schrieb StÃ©phane Ducasse <stephane.ducasse(a)inria.fr>: > > On Aug 22, 2013, at 3:23 PM, Norbert Hartl <norbert(a)hartl.name> wrote: > >> Does pharo support runtime trait composition or does it only work on class definition time. I mean something like >> >> anObject addTrait: MySpecialCapability >> anObject removeTrait: MySpecialCapability > > Nope :) > traits are static :) Sad. You know I was not asking about trait but about runtime composable behavior. I'm not sure what you mean with "traits are static". If traits are static in pharo that's fine. If you think traits are static by design then I was looking for something that has a different name :) Norbert >> >> Norbert > >

Aug. 22, 2013

Re: [Pharo-users] Trait composition on runtime

by StÃ©phane Ducasse

On Aug 22, 2013, at 3:23 PM, Norbert Hartl <norbert(a)hartl.name> wrote: > Does pharo support runtime trait composition or does it only work on class definition time. I mean something like > > anObject addTrait: MySpecialCapability > anObject removeTrait: MySpecialCapability Nope :) traits are static :) > > Norbert > >

Aug. 22, 2013

Re: [Pharo-users] Trait composition on runtime

by Sebastian Tleye

Hi Norbert, You can do anObject setTraitComposition: aTraitComposition but only works for behavior objects 2013/8/22 Jorge Ressia <jorge.ressia(a)gmail.com> > Hi Norbert, > > It sounds like you want something like talents Talents > http://scg.unibe.ch/research/bifrost/talents. > However, there is no running version on pharo 3.0 yet. > > I am not aware of work on object-specific traits, I could be wrong though. > > Cheers, > > > On Thu, Aug 22, 2013 at 3:23 PM, Norbert Hartl <norbert(a)hartl.name> wrote: > >> Does pharo support runtime trait composition or does it only work on >> class definition time. I mean something like >> >> anObject addTrait: MySpecialCapability >> anObject removeTrait: MySpecialCapability >> >> Norbert >> >> >> > > > -- > Jorge Ressia > www.jorgeressia.com >

Aug. 22, 2013

Re: [Pharo-users] Trait composition on runtime

by Jorge Ressia

Hi Norbert, It sounds like you want something like talents Talents http://scg.unibe.ch/research/bifrost/talents. However, there is no running version on pharo 3.0 yet. I am not aware of work on object-specific traits, I could be wrong though. Cheers, On Thu, Aug 22, 2013 at 3:23 PM, Norbert Hartl <norbert(a)hartl.name> wrote: > Does pharo support runtime trait composition or does it only work on class > definition time. I mean something like > > anObject addTrait: MySpecialCapability > anObject removeTrait: MySpecialCapability > > Norbert > > > -- Jorge Ressia www.jorgeressia.com

Aug. 22, 2013