On Wed, May 9, 2012 at 5:57 AM, "Martin v. Löwis" <martin@v.loewis.de> wrote:
On 27.04.2012 09:34, Eric Snow wrote:
On Thu, Apr 26, 2012 at 8:31 AM, Barry Warsaw<barry@python.org>  wrote:
It's somewhat of a corner case, but I think a PEP couldn't hurt.  The
rationale section would be useful, at least.

  http://mail.python.org/pipermail/python-ideas/2012-April/014954.html

Interesting proposal. I have a number of comments:

- namespace vs. dictionary. Barry was using it in the form
 sys.implementation.version. I think this is how it should work,
 yet the PEP says that sys.implementation is a dictionary, which
 means that you would need to write
 sys.implementation['version']

 I think the PEP should be silent on the type of sys.implementation,
 in particular, it should not mandate that it be a module (else
 "from sys.implementation import url" ought to work)

 [Update: it seems this is already reflected in the PEP. I wonder
  where the requirement for "a new type" comes from. I think making
  it a module should be conforming, even though probably discouraged
  for cpython, as it would make people think that they can rely on
  it being a module.

That stems from people arguing over whether sys.implementation should be a dict or a tuple, and people going "it shouldn't be a sequence since it lacks a proper order", but then others saying "it shouldn't be a dict because it isn't meant to be mutated" (or something since I argued for the dict). So Eric (I suspect) went with what made sense to him.
 
I wish there was a builtin class

    class record:
       pass

  which can be used to create objects which have only attributes
  and no methods.

I have heard this request now a bazillion times over the years. Why don't we have such an empty class sitting somewhere in the stdlib with a constructor classmethod to simply return new instances (and if you want to get really fancy, optional keyword arguments to update the instance with the keys/values passed in)? Is it simply because it's just two lines of Python that *everyone* has replicated at some point?

-Brett

 
Making it a type should also work:

   class implementation:
      name = "cpython"
      version = (3,3,0)

 in which case it would an instance of an existing type, namely,
 "type"]

- under-specified attributes: "run-time environment" doesn't mean much
 to me - my first guess is that it is the set of environment variables,
 i.e. a dictionary identical to os.environ. I assume you mean something
 different ...
 gc_type is supposedly a string, but I cannot guess what possible
 values it may have. I also wonder why it's relevant.

Regards,
Martin