otherstack.top().bparams = new BufferParams(buffer_.params());
DocumentClassConstPtr olddc = buffer_.params().documentClassPtr();
buffer_.params() = *undo.bparams;
otherstack.top().bparams = new BufferParams(buffer_.params());
DocumentClassConstPtr olddc = buffer_.params().documentClassPtr();
buffer_.params() = *undo.bparams;