(print 
    (concat
        (->string (+ 2)) " "
        (->string (+ 4 5)) " "
        (->string (+ 0.9)) " "
        (->string (+ 2.9 4)) " "
        (->string (+ 2 4.5)) " "
        (->string (+ 6 7 8 15))))

; 2 9 0.9 6.9 6.5 36