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Date: 04 Feb 2004 13:19:49 +0200
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From: Eli Zaretskii <eliz AT elta DOT co DOT il>
To: djgpp AT delorie DOT com
In-reply-to: <20040204035022.22737.00000765@mb-m19.aol.com> (sterten@aol.com)
Subject: Re: array indices  [i][j]
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> From: sterten AT aol DOT com (Sterten)
> Newsgroups: comp.os.msdos.djgpp
> Date: 04 Feb 2004 08:50:22 GMT
> 
> why should someone want to take a value - and then discard it ?

It is useful when the computation has a side effect.  For example:

   for (x = 1, y = 0, z = 100; x < 100; x++, y++)

Here the expression "x = 1" yields a value of 1, but it also has a
side effect of assigning 1 to x.

> I mean, if this A[i,j,k] isn't really needed, then can't we
> define it to be A[i][j][k] ?

No, we can't, since the basic syntax of C cannot be changed without
changing the language.

>  >  #define MA(i,j,k) A[i][j][k]
>  >
>  >(note the use of parentheses instead of square brackets), or a similar
>  >definition of an inline function.
> 
> very good !

Actually, not very good because using macros to change a syntactic
appearance of a programming language is generally a bad habit.  For
starters, people who read your program will have difficulty
understanding the code.  And you yourself prevent yourself from
learning C faster.