class ActiveFedora::DelegatedAttribute

def writer(obj, v)
  ds = datastream_for_attribute(obj, dsid)
  obj.mark_as_changed(field) if obj.value_has_changed?(field, v)
  if ds.kind_of?(ActiveFedora::RDFDatastream)
    write_rdf(ds, v)
  else
    write_om(ds, v)
  end
end