On May 24, 2012, at 3:14 AM, Gerriet M. Denkmann wrote: > Without Arc, this: > > NSString *s = [ [ NSString alloc ] initWithFormat: ...]; > [ someCollection addObject: s ]; > [ s release ]; > > is clearly more efficient (because not using autoreleasepools) than: > > NSString *s = [ NSString stringWithFormat: ...]; > [ someCollection addObject: s ]; > > But what about Arc? > Is the compiler clever enough to make both versions equally efficient?
Maybe. You can't know if the NSString implementation was itself compiled with ARC. If it was, then there is a *possible* optimization that can avoid the autorelease+retain. However, you can't rely on this. > Or should one still avoid using the convenience method stringWithFormat: ? Are you programming for iOS? The recommendation for that is still to avoid autoreleased objects so as to keep the high-water mark of memory usage down. For Mac OS X it's never been that big a concern except for code in a loop or the like. Regards, Ken _______________________________________________ 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: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to [email protected]
