src/commodities.lisp


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(defpackage :commodities
  (:use :cl)
  (:export :new-commodity
		   :name
		   :price))

(in-package :commodities)

(defclass commodity ()
  ((name :initarg :name
		 :reader name)
   (price :initarg :price
		  :accessor price)))

(defun new-commodity (name price)
  (when (> price 0)
	(make-instance 'commodity
				   :name name
				   :price price)))