underscore.js mixin for checking if an array has a list of values or an object has a list of keys

_has_values.js

_.mixin({
    has_values: function( ){
        var args = _.values(arguments),
            list = args.shift(),
            length = args.length;
        
        if (_.isObject(list))
            list = _.values(list);

        return (_.intersection(list,args).length === length);

    },
    has_keys: function(){
        var args = _.values(arguments),
            list = args.shift(),
            length = args.length;
        
        if (_.isObject(list))
            list = _.keys(list);

        return (_.intersection(list,args).length === length);

    }
});


// Tests and usage

// True
console.log(_.has_values([1,2,3,4], 2, 3));
console.log(_.has_values([1,2,3,4], 2));
console.log(_.has_values([1,2,3,4]));
console.log(_.has_values({a:1,b:2,c:3,d:4 }, 2,3));

// False
console.log(_.has_values([1,2,3,4], 2, 3, 5));
console.log(_.has_values({a:1,b:2,c:3,d:4 }, 2,3,5));