(VAR X Y Z)
(STRATEGY CONTEXTSENSITIVE 
  (from 1)
  (cons 1)
  (s 1)
  (sel 1 2)
  (0)
)
(RULES 
from(X) -> cons(X,from(s(X)))
sel(0,cons(X,Y)) -> X
sel(s(X),cons(Y,Z)) -> sel(X,Z)
)