PCES PI Meeting     Feb 2001
27
Some Simple Programs
•eval : �A ® A
•   eval (x) = let box u = x in u
•quote : �A ® ��A
•   quote (x) = let box u = x in box (box u)
•app : �(A ® B) ® �A ® �B
•   app (f) (x) =
•         let box g = f in
•              let box u = x in box (g u)