Subject: Re: Summary: Thoughts on implementing Scheme in C
From: rpw3@rigden.engr.sgi.com (Rob Warnock)
Date: 2000/11/10
Newsgroups: comp.lang.scheme
Message-ID: <8ugr9o$e163l$1@fido.engr.sgi.com>
 <stephan@pcrm.win.tue.nl> wrote:
+---------------
| Rob Warnock <rpw3@rigden.engr.sgi.com> wrote:
| >And by preallocating all the values for a type (say, characters)
| >in a single array, one can use simple C pointer arithmetic --
| >*without* ugly casts -- to perform things like "char->integer"
| >or "integer->char".
| 
| Not according to ANSI C. Only pointer comparisons where both
| pointers lay in the same array are guaranteed to produce
| meaningful results.
+---------------

Uh... Did you even *read* the text you were objecting to?!?
I *said*, "by preallocating all the values for a type (say,
characters) IN A SINGLE ARRAY"!!  A "single array" is surely
the "same array" as itself, no?


-Rob

-----
Rob Warnock, 31-2-510		rpw3@sgi.com
Network Engineering		http://reality.sgi.com/rpw3/
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