module Util (
+ foldl1',
+
-- general list processing
zipEqual, zipWithEqual, zipWith3Equal, zipWith4Equal,
zipLazy, stretchZipWith,
infixr 9 `thenCmp`
\end{code}
+\begin{code}
+#if __GLASGOW_HASKELL__ < 603
+-- foldl1' was introduce in GHC 6.4
+foldl1' :: (a -> a -> a) -> [a] -> a
+foldl1' f (x:xs) = foldl' f x xs
+foldl1' _ [] = errorEmptyList "foldl1'"
+#endif
+\end{code}
+
%************************************************************************
%* *
\subsection{A for loop}