Laurent Sansonetti
lsans****@apple*****
Sat Dec 9 21:43:11 JST 2006
Hi Kimura-san,
On Dec 9, 2006, at 11:54 AM, kimura wataru wrote:
> Hi,
>
> RubyCocoa automatically converts Array->NSArray and Hash-
> >NSDictionary.
> But treatment of nil value is different between Ruby and Cocoa.
>
> Ruby:
> Array, Hash key, Hash value - allows nil
> Cocoa:
> Array, Hash key - not allows nil
> Hash value - allows nil as NSNull
>
> I wrote a patch to add assertions at conversion and tests.
>
> * raise ArgumentError for a nil value at Array->NSArray conversion
> * raise ArgumentError for a nil key at Hash->NSDictionary conversion
> * use NSNull for a nil value of Hash at Hash->NSDictionary conversion
>
> I think this feature is useful on debugging RubyCocoa applications.
>
Good catch!
However, it looks like NSNull can also be used as NSArray value and
NSDictionary key. Why not always using NSNull?
>> x = NSMutableArray.alloc.init
=> #<OSX::NSCFArray:0x24555e class='NSCFArray' id=0x37b420>
>> x.addObject(NSNull.alloc.init)
=> nil
>> x.objectAtIndex(0)
=> #<OSX::NSNull:0x23f9a6 class='NSNull' id=0xa0277020>
>> d = NSMutableDictionary.alloc.init
=> #<OSX::NSCFDictionary:0x2372ec class='NSCFDictionary' id=0x524500>
>> d.setValue_forKey('xxx', NSNull.alloc.init)
=> nil
>> d.allKeys.to_a
=> [#<OSX::NSNull:0x23f9a6 class='NSNull' id=0xa0277020>]
Laurent