Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/prelude/PreludeList/Foldl1.hs
module Prelude where foldl1 :: (a -> a -> a) -> [a] -> a foldl1 f (x:xs) = foldl f x xs foldl1 f [] = error "PreludeList.foldl1: empty list"
