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0 pointsslurgfest13y ago0 comments

True and False are not 1 and 0 in Python.

     >>> (1 is True) or (True is 1)
    False
    >>> (0 is False) or (False is 0)
    False

    >>> isinstance(0, bool) or isinstance(1, bool)
    False
    >>> isinstance(False, bool) and isinstance(True, bool)
    True

Indexing with boolean expressions is bad style to begin with, but if you are going to do it then a bool cast shows explicitly what you are trying to do.

0 comments

peter-fogg13y ago

You'll find that they are integers, though:

>>> isinstance(True, int)

True

>>> bool.__mro__

(<type 'bool'>, <type 'int'>, <type 'object'>)

Although they aren't literally the same object, 1 == True does evaluate to True.

slurgfestOP13y ago

Downvoting notwithstanding, the statement that 1 and 0 ARE True and False is flat false. It's not even kind of true: True is not 1 and False is not 0, the type of True and False is not int, and the established convention for comparing to these values is to use 'is' if you are not using the vaguer 'if cond' or 'if not cond'.

kzrdude13y ago

You are missing the point. The original code was making detours instead of using True as the list index (which you can do).

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