Eric Snow wrote:
On Mon, Apr 30, 2012 at 3:04 PM, Barry Warsaw firstname.lastname@example.org wrote:
On Apr 27, 2012, at 12:36 AM, Eric Snow wrote:
``sys.implementation`` is a dictionary, as opposed to any form of "named" tuple (a la ``sys.version_info``). This is partly because it doesn't have meaning as a sequence, and partly because it's a potentially more variable data structure.
I agree that sequence semantics are meaningless here. Presumably, a dictionary is proposed because this
cache_tag = sys.implementation.get('cache_tag')
is nicer than
cache_tag = getattr(sys.implementation, 'cache_tag', None)
That's a good point. Also, a dict better reflects a collection of variables that a dotted-access object, which to me implies the potential for methods as well.
Dicts have methods, and support iteration.
A dict suggests to me that an arbitrary number of items could be included, rather than suggesting a record-like structure with an fixed number of items. (Even if that number varies from release to release.)
On the other hand, a dict supports iteration, and len, so even if you don't know how many fields there are, you can always find them by iterating over the record.
Syntax-wise, dotted name access seems right to me for this, similar to sys.float_info. If you know a field exists, sys.implementation.field is much nicer than sys.implementation['field'].
I hate to admit it, but I'm starting to think that the right solution here is something like a dict with dotted name access.
sort of thing.