def (f a b) (a ++ b) def (add a b) (a + b) def (catstrs strs) (foldr f (head strs) (tail strs)) def strs ["aa", "bb"] def (mymap f xs) if ((length xs) == 0) then xs else (: (f (head xs)) (mymap f (tail xs))) def main if (2 < 3) then (print (mymap add [1,2,3,4 , 5])) else (print "")