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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Loops (was Re: do { quit; } else { })
Date: Tue, 03 Feb 2026 03:47:30 -0800
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Xref: csiph.com comp.lang.c:396565

Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:

[...]

> I could write a macro like:
>
> #define ITERATE(var, from, to) for ((var) = (from); (var) < (to); (var)++)
>
> but then anyone reading the code has to understand both how C-style
> for loops work and how the ITERATE macro works.  Does the expansion
> use < or <=?  What happens if "to" is INT_MAX?  Did the author of
> the macro get everything right?

An advantage of using a macro is that these questions need be
answered only once, rather than at every place a for() loop
would appear.

> Now if someone else finds that such a macro makes things easier for
> them, that's fine.  But often, *in my opinion*, such macros make code
> harder to read for someone who knows C well.

Whether using a macro like ITERATE() makes code harder to read
or easier to read is a testable proposition, and as such it
deserves to be treated as a question of fact rather than as
a matter of opinion.