Patches item #1615701, was opened at 2006-12-14 08:08 Message generated for change (Comment added) made by rhettinger You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=305470&aid=1615701&group_id=5470
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Core (C code) Group: Python 2.6 Status: Open Resolution: None Priority: 5 Private: No Submitted By: Walter Dörwald (doerwalter) Assigned to: Nobody/Anonymous (nobody) Summary: Creating dicts for dict subclasses Initial Comment: This patch changes dictobject.c so that creating dicts from mapping like objects only uses the internal dict functions if the argument is a *real* dict, not a subclass. This means that overwritten keys() and __getitem__() methods are now honored. In addition to that the fallback implementation now tries iterkeys() before trying keys(). It also adds a PyMapping_IterKeys() macro. ---------------------------------------------------------------------- >Comment By: Raymond Hettinger (rhettinger) Date: 2006-12-19 16:07 Message: Logged In: YES user_id=80475 Originator: NO I'm -1 on making ANY guarantees about which methods underlie others -- that would constitute new and everlasting guarantees about how mappings are implemented. Subclasses should explicity override/extend the methods withed changed behavior. If that proves non-trivial, then it is likely there should be a has-a relationship instead of an is-a relationship. Also, it is likely that the subclass will have Liskov substitutability violations. Either way, there is probably a design flaw. ---------------------------------------------------------------------- Comment By: Walter Dörwald (doerwalter) Date: 2006-12-19 14:23 Message: Logged In: YES user_id=89016 Originator: YES iteritems() has to create a new tuple for each item, so this might be slower. ---------------------------------------------------------------------- Comment By: Jim Jewett (jimjjewett) Date: 2006-12-19 12:50 Message: Logged In: YES user_id=764593 Originator: NO Why are you using iterkeys instead of iteritems? It seems like if they've filled out the interface enough to have iterkeys, they've probably filled it out all the way, and you do need the value as soon as you get the key. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=305470&aid=1615701&group_id=5470 _______________________________________________ Patches mailing list Patches@python.org http://mail.python.org/mailman/listinfo/patches
