I opened an issue: https://pharo.fogbugz.com/f/cases/12731/Traits-modifications-cause-a-DNU
I marked it as a show stopper because right now you cannot load a package with Traits in the image. I am not sure about triggering the event for subclasses, but I can certainly understand that it can be useful for tools. However, the problem is that we are trying to figure out isPropagation after we trigger it, instead of doing it while triggering for a subclass. So, one possibility would be to distinguish between ClassModified and SuperclassModified. I tried to search in the code quickly but could not locate the exact place. I will try again later if nobody beats me to it. Cheers, Doru On Sun, Jan 26, 2014 at 11:29 PM, Esteban Lorenzano <[email protected]>wrote: > can you propose a fix? > > On 26 Jan 2014, at 22:56, Martin Dias <[email protected]> wrote: > > > > > On Sun, Jan 26, 2014 at 10:50 PM, Martin Dias <[email protected]>wrote: > >> >> >> >> On Sun, Jan 26, 2014 at 4:07 PM, Tudor Girba <[email protected]>wrote: >> >>> I looked more into it, and here is a smaller example: >>> Gofer new >>> smalltalkhubUser: 'Moose' project: 'MooseAlgos'; >>> package: 'Moose-Algos-Graph'; >>> load >>> >>> This one does open the debugger, so the other emergency evaluator issue >>> comes from somewhere else. >>> >>> The problem seems to come from a Trait being defined in this package, >>> and loading this trait triggers ClassModifiedClassDefinition which stumbles >>> in >>> >>> ClassModifiedClassDefinition>>isPropagation >>> "If there is not slot changes, I can assume that there is a propagation >>> (the change is in one of the superclasses)" >>> self oldClassDefinition layout ifNil: [ ^ false ]. >>> ^ self newClassDefinition layout instanceVariables = self >>> oldClassDefinition layout instanceVariables >>> >>> >> Despite of the name of ClassModifiedClassDefinition, it is announced also >> when traits are modified. I don't know if Trait should implement #layout... >> but it is not. >> >> I reproduced using this: >> >> Trait named: #DDDD. >> Trait >> named: #DDDD >> uses: {TSortable} >> category: 'a'. >> >> I guess that ClassModifiedClassDefinition is not only being announced >> when a class changed but also it is being announced when its superclass >> changed (in the case, "propagated"). So the purpose of #isPropagation is >> the check that. But I'm not sure this announcement should be done for the >> subclasses... >> >> >> > Yes, when a class is redefined, the change is announced for subclasses > also. Maybe we shouldn't, no? > > code to reproduce: > > > aClass := Object subclass: #A. > aClass subclass: #B. > > anns := OrderedCollection new. > SystemAnnouncer uniqueInstance > when: ClassModifiedClassDefinition > send: #add: > to: anns. > > Object > subclass: #A > instanceVariableNames: 'a'. > > anns. ---> > an OrderedCollection(a ClassModifiedClassDefinition a > ClassModifiedClassDefinition) > > > > MartÃn > > > -- www.tudorgirba.com "Every thing has its own flow"
