Add missing token.

dvanhorn · dvanhorn · commit a587d3e26fde · 2019-09-19T08:14:22.000-04:00
diff --git a/www/assignments/3.scrbl b/www/assignments/3.scrbl
@@ -173,6 +173,7 @@ which are defined as:
 ;; | 'add1
 ;; | 'sub1
 ;; | 'zero?
+;; | 'if
 ;; | 'cond
 ;; | 'else
 ;; | 'abs
