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

[François Pinard]

[Joshua Marshall]

> [...] if it doesn't make sense to create a sort of boolean which isn't
> in the set { true, false }, then it doesn't make sense to create a
> sort of integer which isn't in the set { ..., -2, -1, 0, 1, 2, ... }.

Merely chatting, here.

In that same big application for which I considered (for a short moment)
sub-classing `bool' to "mark" booleans with their computation origin,
we have a particular other kind-of-boolean type, heavily used in the
application, which runs six values from full falsity to full truth.
Python surely made it very elegant.  This one, I would have never
ever considered sub-typing from `bool' :-). For fun, we named the
constructor `poul' and we speak of pouleans, as a friendly tease to the
mathematician in the team who decided the details of this particular
logic (Jacques Poulin).

About interesting extensions to integers, and to all kind of numbers in
fact, including wet ones :-), a good read is the John Conway book: "On
games and numbers".  However, it is not worth a Python module yet! :-)

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