Haskell Powerset in Lexicographic Order -

i want write powerset function in haskell function declaration of:

powerset :: ord => [a] -> [[a]]

however, i'm trying make lexicographical ordering that:

powerset [1,2,3] = [[], [1], [1,2], [1,2,3], [1,3], [2], [2,3], [3]]

i've found other ways of doing powerset, such as:

powerset = filterm (const [true, false])

but nothing provides powerset in lexographic order. there way write powerset function provide or sort unsorted powerset ordering?

you may right fold:

powerset :: foldable t => t -> [[a]] powerset xs = []: foldr go [] xs     go x acc = [x]: fmap (x:) acc ++ acc

then:

\> powerset [1, 2] [[],[1],[1,2],[2]] \> powerset [1, 2, 3] [[],[1],[1,2],[1,2,3],[1,3],[2],[2,3],[3]]

_{(edited answer remove call tail function)}

Ben