[Rd] Problems with package containing S4 classes

cstrato cstrato at aon.at
Fri Mar 16 23:35:06 CET 2007

Dear Benilton

Yes, but the error disappears only when I define it twice.

For my package I create three files:

1. MyClasses.R:
Here I define the classes only using

2. methods.baseClass.R
Here I define the methods for baseClass
setGeneric("export", function(object,...) standardGeneric("export"))
setMethod("export", "baseClass", export.baseClass);

3. methods.derivedClass.R
Here I define the methods for derivedClass
setGeneric("export", function(object,...) standardGeneric("export"))
setMethod("export", "derivedClass", export.derivedClass);

As you see, I need to define setGeneric twice, otherwise I get the error.
It is not clear to me, why this is the case?

I know, that BioBase has a file AllGeneric.R, but I would like to define
the generics in the respective methods files.

Best regards

Benilton Carvalho wrote:
> do you have a generic for 'export'?
> On Mar 16, 2007, at 5:38 PM, cstrato wrote:
>> Dear Benilton
>> Thank you, now my package works.
>> Do you have an explanation for my second problem:
>> * Installing *source* package 'mytest' ...
>> ** R
>> ** save image
>> Error in setMethod("export", "derivedClass", export.derivedClass) :
>>        no existing definition for function "export"
>> Error: unable to load R code in package 'mytest'
>> Execution halted
>> What may be the reason for this error?
>> Best regards
>> Christian

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