SICP Exercise 2.47 make-frame

Exercise 2.47.  Here are two possible constructors for frames:

(define (make-frame origin edge1 edge2)
  (list origin edge1 edge2))

(define (make-frame origin edge1 edge2)
  (cons origin (cons edge1 edge2)))


For each constructor supply the appropriate selectors to produce an implementation for frames.

SOLUTION

 The code and tests are here.

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