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Re: [Chicken-hackers] The use of the null-pointer and null-pointer? proc
From: |
Peter Bex |
Subject: |
Re: [Chicken-hackers] The use of the null-pointer and null-pointer? procedures |
Date: |
Wed, 11 May 2011 17:14:15 +0200 |
User-agent: |
Mutt/1.4.2.3i |
On Wed, May 11, 2011 at 08:21:32AM -0400, Felix wrote:
> > On Wed, May 11, 2011 at 05:25:12AM -0400, Felix wrote:
> >> > I was wondering what use does (null-pointer?) has.
> >>
> >> Historical. I will deprecate.
> >
> > Thanks, Felix. I noticed the documentation says
> > "Another way to say (address->pointer 0)". Should the address->pointer
> > procedure return #f when given 0?
>
> No, otherwise you couldn't create a pointer object containing a NULL
> pointer... :-) I think we can expect a user to be able to code this.
I understand that this wouldn't be possible. But what is the reason
this has to be possible, considering null pointers are represented
as #f everywhere else? For consistency it would make sense to return
#f here too, but of course you could also argue that it would be more
consistent to always return a pointer...
Ah well
Cheers,
Peter
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