Array.prototype.unique

gistfile1.txt

Array.prototype.unique = (function () {
    var TYPE_MAP = {
        'object'   : 1,
        'function' : 1 
    }   
    return function () {
        var map = {},
            objects = [],
            unique = [];
        for (var i = 0, len = this.length; i < len; i++) {
            var val = this[i];
            
            if (TYPE_MAP[typeof val] && val) {
                if (!val.__unique__) {
                    unique.push(val);
                    objects.push(val);
                    val.__unique__ = 1;
                }
            } 
            else if (!map[val]) {
                unique.push(val);
                map[val] = 1;
            }
        }
        
        for (i = objects.length; i--;) {
            delete objects[i].__unique__;
        }
        
        return unique;
    };
})();