Re: nil pointers

FROM : glenn andreas
DATE : Tue Jul 11 20:07:14 2006

On Jul 11, 2006, at 12:41 PM, Uli Kusterer wrote:

> Am 11.07.2006 um 19:06 schrieb Bill Bumgarner:

>> NSArray *arrayIAmGoingToGetFromSomewhereMaybe = (id) 0x1;

>
>  Whoa! I think I'm going to request that that be made an official 
> constant:
>
> #define INVALID ((id) 0x01)
>
>  that guarantees an access exception. For platforms that have no 
> address that's guaranteed to be invalid, they could always create a 
> singleton that just dies on receiving any message.


How about something more "deadbeef"ish like:

#define COCOA_INVALID ((id) 0xC0C0ABAD)

That way your not likely to get confused with a stray 1 or -1 (for 
example, register coloring may result in sharing a local variable 
with an integer that could easily be 1 or -1, and C0C0ABAD would be 
clearly an "invalid initialized" id instead of an "accidentally 
uninitialized variable")


Glenn Andreas                      <email_removed>
  <http://www.gandreas.com/> wicked fun!
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