title: AssertionError: View function mapping is overwriting an existing endpoint function: main
body: <p>Does anyone know why I can't overwrite an existing endpoint function if i have two url rules like this</p>
  
  <pre><code>app.add_url_rule('/',
                   view_func=Main.as_view('main'),
                   methods=["GET"])
  
  app.add_url_rule('/&lt;page&gt;/',
                   view_func=Main.as_view('main'),
                   methods=["GET"])
  </code></pre>
  
  <p>Traceback:</p>
  
  <pre><code>Traceback (most recent call last): 
    File "demo.py", line 20, in &lt;module&gt; methods=["GET"]) 
    File ".../python2.6/site-packages/flask‌​/app.py", 
      line 62, in wrapper_func return f(self, *args, **kwargs) 
    File ".../python2.6/site-packages/flask‌​/app.py", 
      line 984, in add_url_rule 'existing endpoint function: %s' % endpoint)  
  AssertionError: View function mapping is overwriting an existing endpoint 
      function: main
  </code></pre>