Sat Mar 27 17:52:59 CET 2010
So, the code in rp.ss  seems complete. It implements a generic
dataflow network with bi-directional linking (one direction for pull
functional dependencies and the other for push invalidation
The main idea to make this fit well embedded in Scheme seems to be: to
use ordinary lexical scope for the functional dependencies, and weak
hashes for the inverse dependencies.