Add example on how a Haskeller would write this function

VL2.tex

@@ -494,6 +494,8 @@ square xs = map (\x -> x * x) xs
 
 absList :: [Int] -> [Int]
 absList xs = map (\x -> abs x) xs
+-- a haskeller would write, GHCi...
+absList = map abs
 \end{haskellcode}
 \pause
 Cool, right? So now we have abstracted out the \textbf{recursion pattern} that is all the same for those 3 functions. \code{map} is actually part of the standard library (called \emph{Prelude}).