Why does it cause error when I try to extend JQuery function?
<p>I'm a beginner of Javascript and JQuery. After I learned the source code of jHtmlArea , I try to write the following code,but it return error when I run the code, I don't know what cause error, could you help me? Thanks!</p>

<pre><code>&lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"&gt;
&lt;html xmlns="http://www.w3.org/1999/xhtml"&gt;
&lt;head&gt;
    &lt;title&gt;&lt;/title&gt;
    &lt;script src="Js/jquery-1.7.1.min.js" type="text/javascript"&gt;&lt;/script&gt;
    &lt;script src="Js/SetUI.js" type="text/javascript"&gt;&lt;/script&gt;
    &lt;link href="Css/SetUI.css" rel="stylesheet" type="text/css" /&gt;

    &lt;script type="text/javascript"&gt;
        $(function () {
            var aa="";
            $("#MyDiv").SetUI(aa, "math");
        });
    &lt;/script&gt;
&lt;/head&gt;
&lt;body&gt;
      &lt;div id="MyDiv"&gt;
      &lt;/div&gt; 
&lt;/body&gt;
&lt;/html&gt;




(function ($) {
    $.fn.SetUI = function (editor, opts) {
        if (opts == "math") SetMath.init(this, editor);
    };

    var SetMath = function (obj, editor) {
        init: function () {
            priv.initToolBar(SetMathOptions);
        }
    };

    SetMathOptions = {
        toolbar: [
          ["p", "h1", "h2", "h3", "h4", "h5", "h6"],
          ["cut", "copy", "paste"]
        ],
        toolbarText: {
            p: "Paragraph", h1: "Heading 1", h2: "Heading 2", h3: "Heading 3", h4: "Heading 4", h5: "Heading 5", h6: "Heading 6",
            cut: "Cut", copy: "Copy", paste: "Paste"
        }
    };

    var priv = {
        initToolBar: function (options) {           
        }
    };
})(jQuery);
</code></pre>
