[Python-3000] Types and classes

[Guido van Rossum]

I have no idea what you are saying here (and I did s/since/sense/ :-).

On Wed, Apr 2, 2008 at 3:34 PM, Benjamin Peterson
<musiccomposition at gmail.com> wrote:
>
>
>
>
> On Wed, Apr 2, 2008 at 5:20 PM, Guido van Rossum <guido at python.org> wrote:
> >
> > On Wed, Apr 2, 2008 at 3:03 PM, Amaury Forgeot d'Arc <amauryfa at gmail.com>
> wrote:
> > >  On Wed, Apr 2, 2008 at 11:57 PM, Paul Prescod <paul at prescod.net> wrote:
> >
> > >  >  But does anyone else find it odd that the types of some things are
> > >  >  classes and the classes of some things are types?
> > >  >
> > >  >  >>> type(socket.socket())
> > >  >  <class 'socket.socket'>
> > >  >  >>> type("abc")
> > >  >  <type 'str'>
> > >  >  >>> socket.socket().__class__
> > >  >  <class 'socket.socket'>
> > >  >  >>> "abc".__class__
> > >  >  <type 'str'>
> > >  >
> > >  >  In a recent talk I could only explain this as a historical quirk. As
> I
> > >  >  understand, it is now possible to make types that behave basically
> > >  >  exactly like classes and classes that behave exactly like types. Is
> > >  >  there any important difference between them anymore?
> > >
> > >  I can find one difference:
> > >  - types are written in C
> > >  - classes are written in Python
> > >
> > >  and there is a difference in behaviour:
> > >  most types don't have a writable __dict__, and you cannot add members.
> > >  classes are more flexible.
> >
> > That's more correctly described as the difference between built-in
> > types/classes and user-defined types/classes.
> >
> > I think it's still just a historical quirk; maybe we should bite the
> > bullet and fix this in py3k. (Still, 'type' and 'class' will both be
> > part of the language, one as a built-in function and metaclass, the
> > other as a keyword.)
> Especially because of that I think we should change. list, dict, and set
> aren't metaclasses, so it would make since to fix it.
> >
> >
> > --
> >
> > --Guido van Rossum (home page: http://www.python.org/~guido/)
> >
> >
> >
> >
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>
>
>
> --
> Cheers,
> Benjamin Peterson



-- 
--Guido van Rossum (home page: http://www.python.org/~guido/)