[Python-Dev] sys.implementation

Wed May 9 11:57:59 CEST 2012

On 27.04.2012 09:34, Eric Snow wrote:
> On Thu, Apr 26, 2012 at 8:31 AM, Barry Warsaw<barry at 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. I wish there was a builtin class
 class record:
 pass
 which can be used to create objects which have only attributes
 and no methods. 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