Javascript array, is Sub Set

isSubSet.js

isSubSet = function(ar1, ar2) {
    // Test if ar1 is a subset of ar2
    ar1 = _.uniq(ar1);
    ar2 = _.uniq(ar2);            
    if (ar1.length > ar2.length) {
        return false;
    }
    _.each(ar1, function(el){
        if (ar2.indexOf(el) === -1){
            return false;
        }
    });
    return true;
}

ar1 = [1,2,3];
ar2 = [1,2];
ar3 = [1, 2, "foo"];
b = ["a", "b", "c"];
ar4 = [2, b];
ar5 = [b];

//alert(isSubSet(ar5, ar4));
//alert(isSubSet(ar5, ar5));
//alert(isSubSet(ar4, ar5));
//res = isSubSet(ar1, ar2);
//alert(res);
//res = isSubSet(ar2, ar1);
//alert(res);
//res = isSubSet(ar3, ar2);
//alert(res);
//res = isSubSet(ar2, ar3);
//alert(res);

z = [["foo", "bar"], b];
x = [["foo", "bar"], ["a", "b", "c"], 5];
//alert(isSubSet(z, x));


// BAD CASES ??

//alert(isSubSet([], [1,2,3])); //true - I think this is right.

http://jsfiddle.net/SBwpn/3/