[Rcpp-devel] Create an instance of a reference class for a C++ class exported as a module from within C++?

Sorry for the long subject line but I hope it describes what I want to
do.  I have a C++ class, dgTMatrix, that is exported in a module
definition.

RCPP_MODULE(RcppSp) {
...
   class_<dgCMatrix>("dgCMatrix")
   ...
   ;
}

Many of the methods for this class return other members of this class.
Can I create a new instance of the reference class in R from within
the module?  I'm sure it is possible, I'm just wondering if there is
an easy way to do this without duplicating large chunks of the code in
Rcpp/src/Module.cpp.  Can i somehow clone the SEXP representing the
current instance then swap the external pointer to the C++ object?