As subclassing list has a problem when using __getitem__, __delitem__ and __setitem__ methods with slices (they don't get called because parent implements __getslice__, __delslice__ and __setslice__ respectively), I've coded this UserList class that is a subclass of list, but overwrites these methods. By subclassing this class, you can overwrite __getitem__ and it will be called correctly for slices.
Python, 12 lines
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class UserListSubclass(list): def __getslice__(self, i, j): return self.__getitem__(slice(i, j)) def __setslice__(self, i, j, seq): return self.__setitem__(slice(i, j), seq) def __delslice__(self, i, j): return self.__delitem__(slice(i, j)) # Subclass this class if you need to overwrite __getitem__ and have it called # when accessing slices. # If you subclass list directly, __getitem__ won't get called when accessing # slices as in mylist[2:4].
Tags: list, slices, subclass, __getitem__