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

François Pinard pinard at iro.umontreal.ca
Thu Feb 12 14:41:27 EST 2004

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

and am a bit surprised that `bool' refuses to be sub-classed.  Not that
I cannot live without it, of course!  But it might be useful being
able to "cast" a `bool' into something for which I could control the
representation, while keeping all other properties of `bool'.

Is there a deep reason behind the forbidding?  Or was it merely for
possibly protecting users against themselves? :-) For me, this is a
question, much more than an issue.  Yet, if there is no deep reason,
maybe the forbidding could be lifted?

François Pinard   http://www.iro.umontreal.ca/~pinard

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