[Bioc-devel] methods package is not attached in .onLoad for Biobase

Florian Hahne fhahne at gmx.de
Thu Feb 2 17:31:22 CET 2006

Hi everyone,
I just noticed some strange behaviour when starting R with a saved
workspace containing objects of class cytoFrame or cytoSet. These
classes are defined in my own package prada and make heavy use of
Biobase generics. I get the error

Error in .initContents() : couldn't find function "isGeneric"
Error: .onLoad failed in 'loadNamespace' for 'Biobase'
Fatal error: unable to restore saved data in .RData

When looking at the .onLoad function for Biobase I realized that the
methods package is not attached, thus isGeneric can not be found in the
call to .initContents().
Adding a required(methods) to .onLoad fixed this for me. To my
understanding, attaching methods is mandatory for every package that
uses the S4 system  (at least that's what's stated in the writing R
extensions documentation), so I guess it should be fixed?!

Best wishes,

Florian Hahne
European Bioinformatics Institute
European Molecular Biology Laboratory
Cambridge CB10 1SD
Web: www.ebi.ac.uk

More information about the Bioc-devel mailing list