title: How can I determine in JS if a function/method exists in IE7?
body: <p>I wrote a quick and dirty logger as a jQuery plugin...</p>
  
  <pre><code>(function($){   
      $.log = function(debug) {       
          if (console.debug) {            
              console.debug(debug);           
          };      
      };
  })(jQuery);
  </code></pre>
  
  <p>It works fine in Firefox, but in IE7, I'm getting the error...</p>
  
  <blockquote>
    <p>console.debug is null or not an object</p>
  </blockquote>
  
  <p>How do I perform a function exists in JavaScript that's compatible with IE7?</p>