How to override the [] operator in Python? How to override the [] operator in Python? python python

How to override the [] operator in Python?


You need to use the __getitem__ method.

class MyClass:    def __getitem__(self, key):        return key * 2myobj = MyClass()myobj[3] #Output: 6

And if you're going to be setting values you'll need to implement the __setitem__ method too, otherwise this will happen:

>>> myobj[5] = 1Traceback (most recent call last):  File "<stdin>", line 1, in <module>AttributeError: MyClass instance has no attribute '__setitem__'


To fully overload it you also need to implement the __setitem__and __delitem__ methods.

edit

I almost forgot... if you want to completely emulate a list, you also need __getslice__, __setslice__ and __delslice__.

There are all documented in http://docs.python.org/reference/datamodel.html


You are looking for the __getitem__ method. See http://docs.python.org/reference/datamodel.html, section 3.4.6


matomo