[Python-Dev] RE: Hot-To Guide for Descriptors - Nits! :-)

[Chermside, Michael]

François Pinard writes:
> Would it be more precise to state:
> "... new style objects or classes (those for which the meta-class is a
> subtype of `type')"?  Being sub-classed from object or type is just a
> way, among others, for identifying `type' as the meta-class; but being
> sub-classed from object is not really required.

Raymond Hettinger responds:
> Nope, new-style is taken to mean objects/classes inheriting from
> object/type.  Meta-class objects are neither new-style nor old-style.
> While there is room to argue with this arbitrary distinction, it is
> consistent with Guido's essay and especially relevant to my article
> because most of the rules don't necessarily apply when meta-classes
> are used.  This is because the machinery for descriptors is 
> embedded in type.__getattribute__ and object.__getattribute__.  
> Override or fail to inherit either of these and all bets are off.

Really? I realize the utility of having a term for objects-with-a-
meta-type-of-type, but I had always understood "new-style" to mean
things-that-are-not-old-style-classes. I can live with either
definition, but the Python community should make sure that we use
the term "new-style class" in a consistent fashion.

Did everyone else agree with Raymond so François and I are the odd
men out, or is there a larger confusion over how we use the term?

-- Michael Chermside


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