R help - Sep 2013 - Setting a new method for generic function to satisfy "R CMD check"

Dear All,

Can somebody explain me how to correctly set a new class-specific method
for generic functions (e.g. for "plot", "summary" and
"print"). I simply
programmed these functions with the class names and it works perfectly.
E.g.:

x<-2
y<-3
class(x)<-"newclass"
class(y)<-"newclass"
print.newclass<-function(x){ cat(x*10) }
print(x)
print(y)

However, I need the new methods for a new package, and the "R CMD
check"
gives me warnings that my approach is not correct. I have to define
"methods" and do not use full names as "print.newclass".
I read the "Writing R Extensions" and it is not explained there (at
least
to such level that I could get it) and I didn't get anything understandable
by googling.

Maybe someone can help me?

Many thanks in advance!
Mikhail

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On 13-09-21 3:30 PM, Mikhail Beketov wrote:
> Dear All,
>
> Can somebody explain me how to correctly set a new class-specific method
> for generic functions (e.g. for "plot", "summary" and
"print"). I simply
> programmed these functions with the class names and it works perfectly.
> E.g.:
>
> x<-2
> y<-3
> class(x)<-"newclass"
> class(y)<-"newclass"
> print.newclass<-function(x){ cat(x*10) }
> print(x)
> print(y)
>
> However, I need the new methods for a new package, and the "R CMD
check"
> gives me warnings that my approach is not correct. I have to define
> "methods" and do not use full names as
"print.newclass".
> I read the "Writing R Extensions" and it is not explained there
(at least
> to such level that I could get it) and I didn't get anything
understandable
> by googling.
>
> Maybe someone can help me?
You need to declare methods in the NAMESPACE file, and there is special 
markup for them in Rd files.

Duncan Murdoch