On Fri, Jan 22, 2016, at 08:14 AM, Dave wrote: > > > On 21 Jan 2016, at 23:40, Quincey Morris > > <quinceymor...@rivergatesoftware.com> wrote: > > > > On Jan 21, 2016, at 15:22 , Dave <d...@looktowindward.com > > <mailto:d...@looktowindward.com>> wrote: > >> > >> I’m relying of the copy attribute for the NSString’s, do I need to change > >> these to do a [xxxxxxx copy] too > > > > If you’re writing the setter yourself, you must do the copy yourself. If > > you’re using the synthesized setter, it’s done for you. > > > > In your own code, you may as well be liberal with ‘copy’. It’s basically > > free (in run-time cost) in situations where you don’t need it. You don’t > > save anything by leaving it out. > > > > I’ve always been confused over what *actually* happens when you do > something like this: > > @property (copy) NSString* pString; > > > self.pString = [anotherString copy]; > > Do two new NSString objects get created? (I mean using the synthesized > setter)
No. -copy is equivalent to -retain for immutable strings, so in the best case this code causes zero copies (when anotherString is immutable), and in the worst case it causes one (when anotherString is mutable). --Kyle Sluder _______________________________________________ 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: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
