define(['./filter'], function(filter){

    /**
     * @return {array} Array of unique items
     */
    function unique(arr, compare){
        compare = compare || isEqual;
        return filter(arr, function(item, i, arr){
            var n = arr.length;
            while (++i < n) {
                if ( compare(item, arr[i]) ) {
                    return false;
                }
            }
            return true;
        });
    }

    function isEqual(a, b){
        return a === b;
    }

    return unique;
});