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Re: Help with detecting invalid object when in if() test....
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Re: Help with detecting invalid object when in if() test....


  • Subject: Re: Help with detecting invalid object when in if() test....
  • From: lbland <email@hidden>
  • Date: Fri, 15 Aug 2003 15:17:28 -0400

On Friday, August 15, 2003, at 01:34 PM, Steven M.Palm wrote:

Correction to the last message...

NSLog(@"sig = %d, %@", sig, sig);

I get this consistently when it's bad.

sig = -1609366696, null

Yet a comparison to NULL, nil, or even [NSNull null] doesn't match. Hmmm....

On Friday, August 15, 2003, at 01:46 PM, Steven M.Palm wrote:

if ([sig isEqualTo:NULL])

Actually, I need more sleep... That didn't work either, however, this did....

([sig isEqualTo:[NSNull null]])

What a brain block, and for something so simple.

hi-

on my computer...

printf("[NSNull null]: %d\n", [NSNull null]);

gives this:

[NSNull null]: -1609366696

printf("[[NSNull null] class]: %d\n", [[NSNull null] class]);

gives this:

[[NSNull null] class]: 433168

NSLog(@"[NSNull null]: %@ \n", [[NSNull null] class]);

gives this:

2003-08-15 15:15:21.127 test[752] [NSNull null]: NSNull

... which I never knew. Learn something new every day. Does that explain it? Thanks for bringing that up.

Lance Bland
mailto:email@hidden
VVI
888-VVI-PLOT
http://www.vvi.com
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 >Re: Help with detecting invalid object when in if() test.... (From: "Steven M.Palm" <email@hidden>)

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