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Missing methodΒΆ

I have heard that in Ruby there is a conventional method which is automatically called when a method is missing. You can put code there which will be executed whenever you call a missing method. In Python, there is a similar mechanism exist, but there is one more indirection. If a missing method is called, self.__getattr__ will be called and it needs to return a callable which itself will be called in place of the missing method.

>>> class toto(object):
...     def method(self,string):
...         return string
...     def missing_method(self,*args):
...         return "Warning: method does not exists (you gave %s)" % args
...     def __getattr__(self, *args):
...         return self.missing_method
>>> t = toto()
>>> print t.method("Hello World")
Hello World
>>> print t.unexisting_method("knock knock knock")
Warning: method does not exists (you gave knock knock knock)

10 May 2010