Hi Mike, Given that the caller can pass a NSDictionary or an NSMutableDictionary, I wanted to test its mutability before calling setObject:forKey:. In order to avoid calling mutableCopy each time, I thought it would be more efficient to test it and then call mutableCopy only when needed.
Thanks for the help, -- Tito On Jan 14, 2011, at 12:15 PM, Mike Abdullah wrote: > If you want to test if a dictionary is immutable, you are almost certainly > doing it wrong. When passed a dictionary in to a method either: > > A) Make a mutable copy if that's what you need > B) -copy it if you want it to be immutable. (This is not inefficient as it > sounds because immutable objects implement -copy to do a -retain and return > self instead) > > On 14 Jan 2011, at 10:48, Tito Ciuro wrote: > >> Hello, >> >> Trying to determine whether an NSDictionary is mutable or not fails with >> these two tests: >> >> // Variable info could be NSDictionary or NSMutableDictionary. Assume it's >> an NSDictionary. >> >> BOOL isKindOfClass = [info isKindOfClass:[NSMutableDictionary class]]; >> BOOL respondsToSelector = [info >> respondsToSelector:@selector(setObject:forKey:)]; >> >> After executing the above statements, both variables 'isKindOfClass' >> and'respondsToSelector' are set to YES. >> >> When I obtain the class type of 'info', I get: >> >> (gdb) po [info class] >> NSCFDictionary >> >> The question is: if 'info' is an immutable dictionary, why is isKindOfClass >> and respondsToSelector telling me that it is mutable? >> >> Thanks, >> >> -- Tito >> _______________________________________________ >> >> 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/cocoadev%40mikeabdullah.net >> >> This email sent to cocoa...@mikeabdullah.net > _______________________________________________ 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
