Implement 5.30; on to last section; let's go!

ex-5_23-30.scm

@@ -158,14 +158,38 @@
 
 (display "\nex-5.30 - error-handling\n")
 
+; a
 (set-register-contents! eceval 'exp
   '(begin
      (define (foo x) x)
      (foo a)))
 (start eceval)
 (newline)
-(assert (get-register-contents eceval 'val) 'unbound-variable-error))
+(assert (get-register-contents eceval 'val) 'error-unbound-variable))
+
+; b
+(define (check-apply-division args)
+  (cond
+    ((not (= (length args) 2)) 'error-div-wrong-number-of-args)
+    ((= (cadr args) 0) 'error-div-by-zero)
+    (else 'ok)))
+
+(set-register-contents! eceval 'exp
+  '(begin
+     (/ 1 0)))
+(start eceval)
 (newline)
+(assert (get-register-contents eceval 'val) 'error-div-by-zero)
 
-;; CONTINUE HERE
+(define (check-apply-car args)
+  (cond
+    ((not (pair? (car args))) 'error-car-no-pair)
+    (else 'ok)))
+
+(set-register-contents! eceval 'exp
+  '(begin
+     (car 3)))
+(start eceval)
+(newline)
+(assert (get-register-contents eceval 'val) 'error-car-no-pair)