On Mon, Jul 13, 2009 at 12:53 PM, I. Savant<[email protected]> wrote: > On Jul 13, 2009, at 12:41 PM, Quincey Morris wrote: > >> What you *don't* get for free from subclassing is an internal storage >> mechanism -- you have to invent that for yourself (usually by putting a real >> NSArray instance variable in your subclass :) ). You also need a pretty >> clear understanding of how class clusters work, and that's where confusion >> can set in. > > These two sentences are exactly my point. Perhaps we have differing > opinions of what makes an angry, fire-breathing, treasure-grubbing dragon. > :-)
I agree with Quincey. The difficulty of subclassing a class cluster is often over-stated on this list. There's really not much to it. Just implement the primitive methods - by providing your own storage, or by using a "real" collection object in an instance variable - and bob's your uncle. > What's more (said in an off-list discussion with the OP): It's just not > worth it to say "give me a mutable array with a single instance of a certain > class". Sure, if I wanted an easy way to get a single-element array of Foo, I'd implement +arrayWithSingleFoo on the Foo class. I'd do it that way even if NSArray were not a class cluster - there's no need to create a whole new class just for such a simple task. sherm-- -- Cocoa programming in Perl: http://camelbones.sourceforge.net _______________________________________________ Cocoa-dev mailing list ([email protected]) 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 [email protected]
