Re: Initing sublacss with superclass method

Hi Wolfgang,

nice to read you.

Wolfgang Lux wrote:
> Come on Riccardo, before accusing Apple of lying, you should better check the facts first.:-)

well.. I checked what the code does when "compiled" not only the 
documentation.

on 10.13 XCode indeed has:

+ (NSMutableCharacterSet 
<apple-reference-documentation://hcbtoad_se>*)characterSetWithCharactersInString:(NSString 
<apple-reference-documentation://hcdPnFRdoM>*)aString;


in the documentation box, so as you suppose, perhaps they just 
subclassed and implemented it.
> If you use any of the character set class methods, Xcode says that they return a NSCharacterSet *, which is what you’d expect. It‘s only when you use them for NSMutableCharacterSet that Xcode says that they return a NSMutableCharacterSet *. And that is correct as well, as a quick look at either the online documentation for class NSMutableCharacterSet or at the header NSCharacterSet.h in any recent version of the OS would have revealed: Apple simply has chosen to redeclare (and likely reimplement) all of the class methods In NSMutableCharacterSet to return a NSMutableCharacterSet.
I think I got confused by the class being NSCFCharacterSet

Execution of this code:

     NSMutableCharacterSet *cs;

     cs = [NSMutableCharacterSet characterSetWithCharactersInString:@"a"];
     NSLog(@"class of cs %@ is %@", cs, NSStringFromClass([cs class]));

     if ([cs isKindOfClass:[NSCharacterSet class]])
       NSLog(@"is NSCharacterSet");
     if ([cs isKindOfClass:[NSMutableCharacterSet class]])
       NSLog(@"is NSMutableCharacterSet");

yields this:

2025-07-22 13:21:52.461091+0200 CSTest[606:9532] class of cs 
<__NSCFCharacterSet: 0x1020049b0> is __NSCFCharacterSet
2025-07-22 13:21:52.461141+0200 CSTest[606:9532] is NSCharacterSet
2025-07-22 13:21:52.461165+0200 CSTest[606:9532] is NSMutableCharacterSet

so... it is a NSMutableCharacterSet

and it also means I need to redo the test on 10.4, I got confused by the 
class name __NSCFCharacterSet

Riccardo