(if (= (+ 2 2) 4)
  (println "Maths works!") ; this gets evaluated if 2 + 2 = 4
  (println "UH OH"))       ; this gets evaluated if 2 + 2 != 4
 
;; Uncomment this and you'll get an error.
;(if (= (+ 2 2) 4)
;  (println "Maths works!")
;  (println "Maths still works!")
;  (println "UH OH"))
 
(if (= (+ 2 2) 4)
  (do                               ; all of this gets evaluated if 2 + 2 = 4
    (println "Maths works!")
    (println "Maths still works!"))
  (println "UH OH"))
 
(def does-maths-work (if (= (+ 2 2) 4) "Maths works!" "UH OH"))
 
(println does-maths-work)

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