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POPython decorators that are part of a base class cannot be used to decorate member functions in inherited classes
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copied!<p>Python decorators are fun to use, but I appear to have hit a wall due to the way arguments are passed to decorators. Here I have a decorator defined as part of a base class (the decorator will access class members hence it will require the self parameter).</p> <pre><code>class SubSystem(object): def UpdateGUI(self, fun): #function decorator def wrapper(*args): self.updateGUIField(*args) return fun(*args) return wrapper def updateGUIField(self, name, value): if name in self.gui: if type(self.gui[name]) == System.Windows.Controls.CheckBox: self.gui[name].IsChecked = value #update checkbox on ui elif type(self.gui[name]) == System.Windows.Controls.Slider: self.gui[name].Value = value # update slider on ui ... </code></pre> <p>I've omitted the rest of the implementation. Now this class is a base class for various SubSystems that will inherit from it - some of the inherited classes will need to use the UpdateGUI decorator.</p> <pre><code>class DO(SubSystem): def getport(self, port): """Returns the value of Digital Output port "port".""" pass @SubSystem.UpdateGUI def setport(self, port, value): """Sets the value of Digital Output port "port".""" pass </code></pre> <p>Once again I have omitted the function implementations as they are not relevant. </p> <p>In short the problem is that while I can access the decorator defined in the base class from the inherited class by specifiying it as SubSystem.UpdateGUI, I ultimately get this TypeError when trying to use it: </p> <p><code>unbound method UpdateGUI() must be called with SubSystem instance as first argument (got function instance instead)</code></p> <p>This is because I have no immediately identifiable way of passing the <code>self</code> parameter to the decorator! </p> <p>Is there a way to do this? Or have I reached the limits of the current decorator implementation in Python?</p>

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