[R] Re : Re : ReferenceClasses examples {method}

[Marc Carpentier]

I hadn't found any message on this subject.
Nevertheless you're right again : I've posted this report on r-devel-list where 
it obviously belongs...

Marc




----- Message d'origine ----
De : David Winsemius <dwinsemius at comcast.net>
À : Marc Carpentier <marc.carpentier at ymail.com>
Cc : r-help at r-project.org
Envoyé le : Ven 28 janvier 2011, 18h 59min 16s
Objet : Re: Re : [R] ReferenceClasses examples {method}


On Jan 28, 2011, at 12:35 PM, Marc Carpentier wrote:

> Right. Shame on me : Friday's tiredness ; I don't know why I stuck on that.
> Please just consider the main topic of my message, regarding the example of
> ReferenceClasses (supposing it's appropriate) and sorry for the subsequent
> question...

I'm definitely the wrong one to tackle any S4 or ReferenceClasses questions. 
There have been some discussion on r-devel about how to pick up the 
ReferenceClasses methods but they flew right over my greying head. The latest 
incarnation of Baron's RSiteSearch allows searching the r-devel archives:

http://search.r-project.org/cgi-bin/namazu.cgi?query=ReferenceClasses&max=100&result=normal&sort=score&idxname=functions&idxname=Rhelp10&idxname=R-devel


And maybe other search strings could be even more productive, since I only tried 
one. I would have thought the ReferenceC;asses part of your question to be more 
appropriate for r-devel anyway.

--David.



> 
> 
> ----- Message d'origine ----
> 
> De : David Winsemius <dwinsemius at comcast.net>
> À : Marc Carpentier <marc.carpentier at ymail.com>
> Cc : r-help at r-project.org
> Envoyé le : Ven 28 janvier 2011, 17h 39min 59s
> Objet : Re: [R] ReferenceClasses examples {method}
> 
> 
> On Jan 28, 2011, at 11:05 AM, Marc Carpentier wrote:
> 
>> Dear help, dear John Chambers,
>> I'm trying to learn OOP-possibilities in R and I was going through the
>> documentation 'ReferenceClasses {methods}'. (great work, by the way...)
>> Reading associated Examples, something bothers me : it seems to me that there
>> are errors in 'edit' and 'undo' methods. I think that :
>> - 'undo' should update 'edits' field with :
>> length(edits) <<- length(edits) - 1 #(and not - 2)
>> - and for coherence, 'edit' should store modifications in an 'append'-style :
>> edits <<- c(edits,list(backup)) #as opposed to c(list(backup),edits)
>> 
>> I hope I'm not wrong.
>> 
>> As a complementary question, suppose one kept 'c(edits,list(backup))', does
>> anyone know how todiscard first element(s) of a list? For a vector :
>> vedits<<-vedits[-1]
>> But lists can't be selected that way ( edits<<- edits [[-1]] #wrong )
> 
> You are confusing "[" and "[["
> 
>> ll <- list(a=1,b=2,cc=3)
>> ll[-1]
> $b
> [1] 2
> 
> $cc
> [1] 3
>> 
> --
> David Winsemius, MD
> West Hartford, CT
> 
> 
> 

David Winsemius, MD
West Hartford, CT