learning-sicp

My embarrassing half assed SICP run.
git clone https://kaka.farm/~git/learning-sicp
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exercise-39.scm (541B)

      1 ;; Exercise 2.39
      2 
      3 (define (exercise-2.39)
      4   (define (reverse-my-fold-right sequence)
      5     (my-fold-right
      6      (lambda (x y)
      7        (append y
      8                (list x)))
      9      '()
     10      sequence))
     11 
     12   (define (reverse-my-fold-left sequence)
     13     (my-fold-left
     14      (lambda (x y)
     15        (append (list y)
     16                x))
     17      '()
     18      sequence))
     19 
     20   (test-begin "2.39")
     21   (test-equal
     22       '(4 3 2 1)
     23     (reverse-my-fold-right '(1 2 3 4)))
     24   (test-equal
     25       '(4 3 2 1)
     26     (reverse-my-fold-left '(1 2 3 4)))
     27   (test-end "2.39"))
     28 
     29 (exercise-2.39)