Another way to do it is to use CFDictionaryRef and use the integers directly.
NSInteger type; dateFormatterStorage = CFDictionaryCreateMutable( kCFAllocatorDefault, 0, 0, &kCFTypeDictionaryValueCallBacks ); formatter = (NSDateFormatter*)CFDictionaryGetValue( dateFormatterStorage, (void*)type); CFDictionarySetValue( dateFormatterStorage, (void*)type, formatter ); Perfectly legal and something recommended to us at one of the performance talks at WWDC. On Oct 29, 2010, at 6:29 AM, Graham Cox wrote: > I have a need to associate objects with an arbitrary unsigned integer, which > can be pretty much anything. I figured a dictionary with NSNumbers as keys > would be perfect, where the NSNumber is created using > +numberWithUnsignedInteger: > > Trouble is, each time I create the number, it's a new object even if it > contains a value NSNumber has seen before, so the lookup fails. > > So, I thought I'd just create suitable static NSNumbers, but I have the same > problem in another place, since I then need to know which static NSNumbers > I've allocated already to a given integer, which means looking them up. While > I could just add them to an array and conduct a linear search - for the > current situation efficiency isn't likely to be an issue - this solution > wouldn't scale very well if it ever needed to. > > Is there an obvious alternative I'm overlooking? > > --Graham > > > _______________________________________________ > > Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) > > Please do not post admin requests or moderator comments to the list. > Contact the moderators at cocoa-dev-admins(at)lists.apple.com > > Help/Unsubscribe/Update your Subscription: > http://lists.apple.com/mailman/options/cocoa-dev/alex%40webis.net > > This email sent to a...@webis.net Alex Kac - President and Founder Web Information Solutions, Inc. "Champions aren't made in the gyms. Champions are made from something they have deep inside of them - a desire, a dream, a vision. They have last-minute stamina, they have to be a little faster, they have to have the skill, and the will. But the will must be stronger than the skill." -- Muhammad Ali _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
