Python: how to get error from list[-1]? -


is there way return error index value [-1]?

>>>l=[1,2,3] >>>l[-1] error:list index out of range

not built-in list type, can define own class has stricter indexing rules:

>>> class strictlist(list): ...     def __getitem__(self, index): ...             if index < 0: ...                     raise indexerror("negative integers forbidden") ...             return list.__getitem__(self, index) ... >>> seq = strictlist([1,2,3]) >>> seq[-1] traceback (most recent call last):   file "<stdin>", line 1, in <module>   file "<stdin>", line 4, in __getitem__ indexerror: 'negative integers forbidden'

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