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Equality of negated True/False and None

When implementing a board game, a board cell can be in one of the three different possible states available: True (cell occupied by first player), False (cell occupied by second player) or None (cell is empty).

My question is that:

Why does 

not(True) == None 
return True

whereas that it should actually return False?

And why does 

not(False) == None 
return True

whereas that it should actually return False?

Could this be a possible bug in Python that should be reported up to the developers, whom from among them, as soon as possible?

Solution

  • not is not a function, and not(True) is not a function call.

    not(True) == None is parsed as not (True == None), because not has lower precedence than ==.

    Please keep Python's operator precedence in mind when writing expressions, and don't treat things like functions if they're not functions.