[R-pkg-devel] S4 methods

Sebastian Meyer @eb@meyer @end|ng |rom |@u@de
Tue Jun 2 12:12:15 CEST 2020

This is a new check in R-devel. The NEWS say:

> R CMD check etc now warn when a package exports non-existing S4 classes or methods, also in case of no "methods" presence

In your case, the NAMESPACE contains

> exportClasses(classify)

> exportClasses(gonad_mature)

> exportClasses(morphMat)

but your package does not define these S4 classes.

You seem to instruct roxygen2 to create these invalid directives using
@exportClass tags manually instead of just @export. Simply remove these
wrong @exportClass tags from your source files and regenerate your

Best regards,

	Sebastian Meyer

Am 02.06.20 um 10:01 schrieb Edgar Josymar Torrejón-Magallanes:
> Dear members
> I just finished some minor updates to an R package (sizeMat) I've had on
> CRAN (haven't had to update in a month). My package passes Check on my
> local machine, but it just bounced back from CRAN with the message
> Warning: S4 exports specified in 'NAMESPACE' but not defined in package
> 'sizeMat'
> I use roxygen2 to build my package NAMESPACE and don't have any S4 exports
> that I'm aware of.
> Perhaps this might be related to changes in R version 4.0.0?
> How could I fix this problem?
> Thanks.

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