I did send a ~200KB patch do Dan (I supposed it to be to big for the list).
It implements the proposed class hierarchy: default ... implementing almost nothing, throwing exceptions | | | scalar ... most of previous default | | | perlint, perlnum, ... Sub Continuation .... It's not finished, there are many questions ("bitwise or" for perlnum ....), some other issues (copy a string or not) and so on. But, it is IMHO a starter, to get towards a consistent class interface - and it run's all tests ok. So if someone else is interested in looking at it, I'll send a copy. Thanks, leo