Wed Aug 5 15:49:26 CEST 2009

Unsafe pointers

I get it now: by making sure the atom_class pointer is the slot one
_before_ the atom pointer, it is possible to write unsafe functions
without too much hassle.

The free() pointer is stored in a class object.  This class object is
the value's type.  Some values however are only statically typed, and
appear as unsafe pointers if they make it into Scheme land.