Tue Mar 27 11:13:48 EDT 2007

the road to PF

ok. time to write PF in forth, by gradually bootstrapping into
different languages. the lifts are:

1. vector -> linear lists
2. non-managed -> refcount managed
3. untyped -> type/polymorph
4. proper GC
5. scheme

the first lift is the same as the one i already did, which is lifting
native code to vectored rep. the lower interpreter's composites become
the higher interpreter's primitives. however, if data is also being
lifted, the change is in no way trivial: primitives won't accept the
data until it's moved to a linear stack.

so maybe this needs to be separated. the lift to lists is different
for data than it is for code. on the other hand, it does look like a
nice place to insert some type checking code.

need to think a bit more..