Pitfalls ...

• Repeating arguments can cause exponential computation duplication: [Jones et al., p. 119.]

  
  (defun f (n)
    (if (= n 0)
        1
        (g (f (- n 1)) ) ) )
  
  (defun g (m) (+ m m))
  

• The user should not have to understand the logic of the output program, nor understand how the partial evaluator works.

• Speedup of partial evaluation should be predictable.

• Partial evaluation should deal with typed languages and with symbolic facts, not just constants.