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A general pattern of classes with inheritance
The following shows a template of a function that serves as a subclass of another class
(define (class-name parameters)
 (let ((super (new-part super-class-name some-parameters))
       (self 'nil))
   (let ((instance-variable init-value)
     (define (method parameter-list)
     (define (dispatch message)
       (cond ((eqv? message 'selector) method)
             (else (method-lookup super message))))
     (set! self dispatch))
A simulation of the root of a class hierarchy.
Accompanying functions for instantiation, message passing, and method lookup.