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Evaluation of Dylan Expressions (20 points)

Determine the value to which the following Dylan expressions evaluate and draw a box around the resulting value. You need not show the steps in the substitution model needed to calculate the value.

a.

(head ((method (x) (pair x '())) 3))

 

b.

(((method (x) (method (f) (f x))) 3) (method (y) (+ 2 y)))

 

c.

(tail (head (tail (pair 1 (pair (pair 2 (pair (pair 3 4) 5)) 6)))))

 

d.

(define foo (method (x) (method (y) (+ x y))))
(define bar (foo 3))
(+ (bar 4) (bar 7))

e.

((method (f) (method (x) (f 1 (f 2 x)))) +)

 

f.

(define baz 
   (method (f x a)
     (bind-methods 
       ((frob (y z) 
          (if (null? y) z (frob (tail y) (f (head y) z)))))
      (frob x a))))

(baz + (list 1 2 3) 0)

Next: Analysis of Algorithms (30 Up: CS212 Preliminary Exam I Previous: CS212 Preliminary Exam I