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Re: NSNull and @""
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Re: NSNull and @""


  • Subject: Re: NSNull and @""
  • From: "Kyle Sluder" <email@hidden>
  • Date: Sat, 11 Oct 2008 14:03:45 -0400

On Sat, Oct 11, 2008 at 1:57 PM, Seth Willits <email@hidden> wrote:
> If it's what I think you're talking about then: No, nil is used as a marker
> for the variable argument list to say "this is the end of the list." It's
> not actually inserted into the dictionary at all. Why it's required is
> really beyond me, but it's simply an Obj-C syntax thing.

It's required because the arguments are simply passed on the stack one
after the other.  Their size is known from the type, but not their
number.  The nil is a sentinel so the code doesn't simply fall off the
end of the stack and into garbage memory looking for parameters.

--Kyle Sluder
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References: 
 >NSNull and @"" (From: DKJ <email@hidden>)
 >Re: NSNull and @"" (From: Seth Willits <email@hidden>)
 >Re: NSNull and @"" (From: Ian Joyner <email@hidden>)
 >Re: NSNull and @"" (From: Seth Willits <email@hidden>)
 >Re: NSNull and @"" (From: "Stelian Iancu" <email@hidden>)
 >Re: NSNull and @"" (From: Seth Willits <email@hidden>)

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