[Python-Dev] bool does not want to be subclassed?

Bob Ippolito bob at redivi.com
Thu Feb 12 15:02:38 EST 2004

On Feb 12, 2004, at 2:50 PM, Aahz wrote:

> On Thu, Feb 12, 2004, François Pinard wrote:
>> Hi, people.  I just noticed this:
>>>>> class booleen(bool):
>> ...   def __repr__(self):
>> ...     if self:
>> ...         return "Vrai"
>> ...     return "Faux"
>> ...
>> Traceback (most recent call last):
>>   File "<stdin>", line 1, in ?
>> TypeError: type 'bool' is not an acceptable base type
> Just to bolster Francois's case, I ran into this precise use case a 
> week
> ago myself (where I wanted a bool but needed to change the output
> string).  Didn't bother complaining about it, though.  ;-)

Shouldn't you be "adapting" the objects for display with some kind of 
value transformer.. instead of trying to change the objects themselves 
in the "model"?  You could do this with something like PyProtocols, for 
example.  You really have to do something like this in most cases 
anyway, because __repr__ gets coerced to str if you use the repr() 


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