[Python-3000] PEP 3133: Introducing Roles

Steven Bethard steven.bethard at gmail.com
Wed May 16 01:43:53 CEST 2007

On 5/15/07, Collin Winter <collinw at gmail.com> wrote:
> On 5/14/07, Steven Bethard <steven.bethard at gmail.com> wrote:
> > On 5/14/07, Collin Winter <collinw at gmail.com> wrote:
> > > You may like adding the extra complexity
> > > and indirection to the VM necessary to support
> > > issubclass()/isinstance() overriding, but I don't.
> >
> > Have you looked at Guido's issubclass()/isinstance() patch
> > (http://bugs.python.org/1708353)?  I'd hardly say that 34 lines of C
> > code is substantial "extra complexity".
> This is what I don't understand: ABCs require changing the VM, roles
> don't; all that change buys you is the ability to spell "performs()"
> as "isinstance()".

Sorry, I can't really respond to this until you give me some idea what
your implementation is.  You keep saying that roles don't require
changing the VM, but I don't know what they *do* involve changing. So
I can't judge how different that is from allowing isinstance() to be

I'm not *in*-sane. Indeed, I am so far *out* of sane that you appear a
tiny blip on the distant coast of sanity.
        --- Bucky Katt, Get Fuzzy

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