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Exercise solution:
Generation of get-prop

Here is my solution:

 (define (configure-get-prop comparison not-found-value)
  (letrec ((get-prop
             (lambda (key property-list)
               (cond ((null? property-list) not-found-value)
                     ((null? (cdr property-list))
                      (error "Malformed property list"))
                     ((comparison key (car property-list))
                      (list key (car (cdr property-list))))
                     (else (get-prop key (cdr (cdr property-list))))))))
    get-prop))

Notice the use of the letrec namebinding in order to provide for recursion in the generated function.