Check if two lists have the same elements

Question

I'm trying to write a function wich given two lists returns a boolean responding if the two lists have the same elements, even if they do not appear in the same order. I've got something like this:

function :: [a] -> [a] -> Bool
function (x:xs) y = elem x y && function xs y

The problem with this is that there's no pattern when xs is empty, and I do not have any idea how to deal with that case. Any other way to solve this will be really welcome, I am quite new to Haskell.

Thanks all!

Answer 1

This works as well

import Data.List

function :: (Eq a) => [a] -> [a] -> Bool
function x y = null (x \\ y) && null (y \\ x)

Answer 2

Use the clause:

function [] y = True

All the elements of the empty list are in the list y.