&rest some bindings
added get-slot-value which elides boundedness errors and supports calling with slot-defs
Made accesses allow specification of type which is particularly needed
on setting

eg: (setf (accesses foo '(:a :type :plist) '(:b :type :alist)) 15 )

Now works correctly even in light of foo being nil and the value of a
being nil.  This is important if something is expecting an ALIST and
is currently nil