Preparing plugin for $.plugin() usage instead of $(selector).plugin()
<p>Simply:</p>

<pre><code>(function($){
    $.fn.plugin = function()
    {
        // results in error
        // when called like
        // $.plugin();
    }
})(jQuery);
</code></pre>

<p>The error is (copied from Chrome console): </p>

<pre><code>Uncaught TypeError: Object function ( selector, context ) {
        // The jQuery object is actually just the init constructor 'enhanced'
        return new jQuery.fn.init( selector, context, rootjQuery );
    } has no method 'plugin'
</code></pre>

<p>What rules I have to follow in order to make my plugin work without the element selection?</p>
