From: "John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Newbie Question: Index lookup coord. checking...
Date: Mon, 28 Jul 1997 20:12:42 +0000
Organization: Two pounds of chaos and a pinch of salt
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Badman wrote:
> 
> Hello, I have a simple question: Can you check coordinates for an index
> lookup (so you don't get an error) and check that same index in the same
> if() statement?
[examples snipped]

Yes; the order of logical processing in C requires that this be safe to
do; the evaluation of a truth expression is halted once the truth or
falsehood is known.  But I would recommend handling the out of range
errors separately; they may signify bugs in your program.

-- 
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|      John M. Aldrich       | "It may be better to be a live jackal|
|       aka Fighteer I       | than a dead lion, but it is better   |
|   mailto:fighteer AT cs DOT com   | still to be a live lion."            |
| http://www.cs.com/fighteer |                - Lazarus Long        |
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