But names in the AC are, in a sense, global by default, unless restricted explicitely.
So, the question is: How much would I lose if I changed AC to have all names' scopes restricted by default to some local context in each process, and only allowing external references by some sort of 'importing' mechanism.
My feeling is that, at least from a 'practical' point of view, not much would be lost, but I don't yet have enough understanding of the theory to be able to assert that with confidence.
it would probably depend on what your "importing mechanism" can and cannot do. if you have no restrictions on scope extension, you should be OK. many subcalculi of pi have been looked at where you can export only restricted names, and the results are generally nice. the first paper to study this is
pi-calculus, internal mobility and agent-passing calculi
(ftp://ftp-sop.inria.fr/mimosa/personnel/davides/piI.ps.gz)by davide sangiorgi.
martin