exam2.4.1

;; mht created on Nov 8, 2011

;; Errors
;(+ (10) 20)
;; to produce : function call (10) : expected a name after an open parentesis, but found a number

;(10 + 20)
;; to produce : function call (10 : expected a name after an open parenthesis, but found a number

(+ +)
;; to produce : +: expectes argument of type <number>; given +