p10.scm

;;; P10 - Evaluación Matemática

(define mateval
  (lambda (expr)
    (cond
      ((number? expr) expr)
      (else
        (cond
          ((eqv? 'ADD (car expr)) (+
                                    (mateval (cadr expr))
                                    (mateval (caddr expr))))
          ((eqv? 'SUB (car expr)) (-
                                    (mateval (cadr expr))
                                    (mateval (caddr expr))))
          ((eqv? 'MUL (car expr)) (*
                                    (mateval (cadr expr))
                                    (mateval (caddr expr))))
          ((eqv? 'DIV (car expr)) (/
                                    (mateval (cadr expr))
                                    (mateval (caddr expr))))
          ((eqv? 'MOD (car expr)) (remainder
                                    (mateval (cadr expr))
                                    (mateval (caddr expr)))))))))

;;; Prueba

(print (mateval '(ADD 3 (MUL 2 5))))
(print (mateval '(MOD 10 (MUL (DIV 8 4) (SUB 5 3)))))