Re: (0 == foo), rather than (foo == 0)

From: Willy Tarreau
Date: Thu Mar 11 2004 - 02:08:12 EST


On Wed, Mar 10, 2004 at 06:36:22PM -0800, Linus Torvalds wrote:
> And while "0 == foo" may be logically the same thing as "foo == 0", the
> fact is, the latter is what people are used to seeing. And by being used
> to seeing it, they have an easier time thinking about it.
> As a result, using the former just tends to increase peoples confusion by
> making code harder to read, which in turn tends to increase the chance of
> bugs.

I have a friend who constantly uses it, and his code is unreadable, because
sometimes, a "0 == xxx" becomes "0 <= xxx" or "0 >= xxx" which is difficult
to understand. Thinking that xxx is negative because it's written on the
right side of a >= is complicated. And the worst he does is when he uses
functions :

if (0 < strcmp(a, "xxx")) ...
if (sizeof(t) > read(fd, t, sizeof(t)) ...

I have already helped him track bugs in his programs, and some of them were
just related to this usage, because nobody's brain can understand these
constructions immediately without thinking a bit. So I'm all against this
sort of thing.


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at