Type comparison warning
I'm probably missing something simple, but I don't understand why this line: return (i == -1 ? [NSNull null] : [NSNumber numberWithInteger:i]); (where i is an NSInteger) produces this warning: comparison of distinct Objective-C types lacks a cast (The return type of the method is id.) ___ 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 [EMAIL PROTECTED]
Re: Type comparison warning
On Oct 30, 2008, at 10:12 AM, DKJ wrote: I'm probably missing something simple, but I don't understand why this line: return (i == -1 ? [NSNull null] : [NSNumber numberWithInteger:i]); (where i is an NSInteger) produces this warning: comparison of distinct Objective-C types lacks a cast (The return type of the method is id.) The ternary conditional operator requires that both sides of the : are the same type. In your case, one is a NSNull* and one is a NSNumber*, and C has no idea that a NSNull* and a NSNumber* are in any way the same kind of pointer, which means that it has no idea what the type of the overall statement is. This would compile: return (i == -1 ? (id)[NSNull null] : (id)[NSNumber numberWithInteger:i]); -- Dave Carrigan [EMAIL PROTECTED] Seattle, WA, USA PGP.sig Description: This is a digitally signed message part ___ 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 [EMAIL PROTECTED]
Re: Type comparison warning
First off, NSInteger is an object not an int and can't be directly compared to an int. Second, i is not likely an NSInteger, it's a pointer to an NSInteger, which means it can be compared to an int, via implicit or explicit casting, but in the absence of an explicit cast, the compiler assumes that's probably not what you intended to do. Next, NSNull NSNumber are distinct types; the ternary operator wants both potential returns to be of the same type (or compatible types for some meaning of compatible), so the compiler will warn you about that once you fix the first problem. Just cast both to id and you'll be fine--assuming the code that receives this id properly handles the fact that it may point to different types. I started to say this is all basic C stuff, but that's not quite fair. It's the intersection of Objective-C extensions with the basic C rules, which still hold true. -- Scott Ribe [EMAIL PROTECTED] http://www.killerbytes.com/ (303) 722-0567 voice ___ 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 [EMAIL PROTECTED]
Re: Type comparison warning
On Thu, Oct 30, 2008 at 10:47 AM, Scott Ribe [EMAIL PROTECTED] wrote: First off, NSInteger is an object not an int and can't be directly compared to an int. Not true, NSInteger and NSUInteger are typedefs for plain integer types, *not* Objective-C objects. -- Clark S. Cox III [EMAIL PROTECTED] ___ 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 [EMAIL PROTECTED]
Re: Type comparison warning
Not true, NSInteger and NSUInteger are typedefs for plain integer types, *not* Objective-C objects. Yes, yes, yes. Thanks for pointing that out. I'm not doing 10.5-only development yet, so I read NSNumber because I'm not used to seeing NSInteger anywhere. -- Scott Ribe [EMAIL PROTECTED] http://www.killerbytes.com/ (303) 722-0567 voice ___ 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 [EMAIL PROTECTED]
Re: Type comparison warning
Le 30 oct. 08 à 19:01, Scott Ribe a écrit : Not true, NSInteger and NSUInteger are typedefs for plain integer types, *not* Objective-C objects. Yes, yes, yes. Thanks for pointing that out. I'm not doing 10.5-only development yet, so I read NSNumber because I'm not used to seeing NSInteger anywhere. NSInteger can safely be used for developpement that target any OS 10 version (it is binary compatible with previous OS X version). All my projects that target 10.4 already use NSInteger (and are 64 bits safe). ___ 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 [EMAIL PROTECTED]
Re: Type comparison warning
All my projects that target 10.4 already use NSInteger (and are 64 bits safe). I got an error when I first tried. Perhaps that was with a project that still supports 10.3.9... -- Scott Ribe [EMAIL PROTECTED] http://www.killerbytes.com/ (303) 722-0567 voice ___ 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 [EMAIL PROTECTED]
Re: Type comparison warning
On Oct 30, 2008, at 6:03 PM, Scott Ribe wrote: I got an error when I first tried. Perhaps that was with a project that still supports 10.3.9... If you're using an older SDK, then you can support NS(U)Integer and CGFloat in your older code just by copying the definitions from the Leopard SDK, taking out all of the 64-bit code (__LP64__), and putting the definitions in a place where they will be loaded _after_ the Foundation framework headers but _before_ your own code. This will help you get ready for 64-bit development when you're ready to take the plunge. Nick Zitzmann http://www.chronosnet.com/ ___ 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 [EMAIL PROTECTED]
