[Haskell-cafe] List of numbers to list of ranges

Hi all, Here's my attempt to convert a list of integers to a list of range tuples - Given [1,2,3,6,8,9,10], I need [(1,3),(6,6),8,10)] My attempt using foldl yields me the output in reverse. I can ofcourse reverse the result, but what would be a better way? f xs = foldl ff [] xs where [] `ff` i = [(i,i)] ((s,e):ns) `ff` i = if i == e+1 then (s,i):ns else (i,i):(s,e):ns Regards, Kashyap