What does arguments reference when used as an argument?
<p>Here is _.extend from <a href="http://underscorejs.org/" rel="nofollow">underscore</a>.</p>

<pre><code>  // Extend a given object with all the properties in passed-in object(s).
  _.extend = function(obj) {
    each(slice.call(arguments, 1), function(source) {
      if (source) {
        for (var prop in source) {
          obj[prop] = source[prop];
        }
      }
    });
    return obj;
  };
</code></pre>

<p>The function <code>call</code> expects a this value followed by a list of arguments.</p>

<p>If the only argument passed is '1', then slice will return an array omitting the first item.</p>

<p>However, how can arguments be used as a this value as defined my MDN.</p>

<p>MDN</p>

<p><a href="https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Function/call" rel="nofollow">call</a></p>

<p><a href="https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Array/slice" rel="nofollow">slice</a></p>

<p><a href="https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Functions_and_function_scope/arguments" rel="nofollow">arguments</a></p>
