Am Sonntag, 10. April 2005 19:46 schrieb Daniel Fischer: > > so it doesn't work in all cases. The idea is nice, though: > > > > import Data.Maybe > > > > finit = catMaybes . foldr f [Nothing] . map Just > > where > > f x ys = case ys of > > [Nothing] -> [] > > _ -> x:ys > > > > will do fine. > > Ooooops, only for nonempty lists!
Replace catMaybes with 'map (maybe (error "init of []") id)' and it'll work also for empty lists. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
