NSString question...

• T Reaves NSString question... Dec 16 2003, 14:00
  If I have two lines of code:
  NSSLog("Test");
  NSLog(@"Test");
  I know that the first line is wrong, and the second line is correct.
  But I was wondering what the actual difference is?  I made the mistake
  of doing the first one, and got a sig11.
  
  Just wondering.
• SD Re: NSString question... Dec 16 2003, 14:15
  "Test" is just an array of characters.
  
  @"Test" is a NSString object.
  
  NSLog expects to have an NSString object as the first argument.  If
  you give it something else, it will try to read it as a NSString.
  Probably causing a crash or other funniness.
  
  SD
• Chad Leigh -- ObjectWerks Inc. Re: NSString question... Dec 16 2003, 14:18
  On Dec 16, 2003, at 2:58 PM, T Reaves wrote:
  
  

  > If I have two lines of code:
  > NSSLog("Test");
  

  
  this is a c string  (char* or variant)
  
  

  > NSLog(@"Test");
  

  
  this is a NSString* .
  
  

  > I know that the first line is wrong, and the second line is correct.
  > But I was wondering what the actual difference is?  I made the mistake
  > of doing the first one, and got a sig11.
  

  
  Since NSLog() looks for an NSString* argument, it tries to message your
  c string and since it is not an object it fails
  
  Chad
  
  

  >
  > Just wondering.
  
• Shawn Erickson Re: NSString question... Dec 16 2003, 14:26
  On Dec 16, 2003, at 1:58 PM, T Reaves wrote:
  
  

  > If I have two lines of code:
  > NSSLog("Test");
  > NSLog(@"Test");
  > I know that the first line is wrong, and the second line is correct.
  > But I was wondering what the actual difference is?  I made the mistake
  > of doing the first one, and got a sig11.
  >
  > Just wondering.
  

  
  Well @" ... " tells the compiler to create a NSString instance
  (actually a constant string subclass of NSString) while " ... " is just
  a plain old null terminated C string. I am sure this is covered in
  Apple's Objective-C docs, which can be found online.
  
  In the case of NSLog it expects an object not a null terminated string.
  
  -Shawn
• Fabien Roy Re: NSString question... Dec 16 2003, 17:45
  This would work also (printf like syntax for printing scalars and
  CStrings):
  NSSLog(@"%s %d","Test",1);
  
  On Dec 16, 2003, at 2:23 PM, Shawn Erickson wrote:
  
  

  >> If I have two lines of code:
  >> NSSLog("Test");
  >> NSLog(@"Test");
  >> I know that the first line is wrong, and the second line is correct.
  >> But I was wondering what the actual difference is?  I made the
  >> mistake of doing the first one, and got a sig11.
  >>
  >> Just wondering.