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From: karl@haddock.ima.isc.com (Karl Heuer)
Newsgroups: comp.lang.c
Subject: Re: Using Macros
Message-ID: <17332@haddock.ima.isc.com>
Date: 9 Aug 90 22:40:33 GMT
References: <362.26be9dcc@astro.pc.ab.com> <21057@grebyn.com> <642@travis.csd.harris.com> <17298@haddock.ima.isc.com> <46860@brunix.UUCP> <10881@crdgw1.crd.ge.com> <1752@tuvie>
Reply-To: karl@kelp.ima.isc.com (Karl Heuer)
Organization: Interactive Systems, Cambridge, MA 02138-5302
Lines: 21

The source of the problem is the name of the macro.  It's not at all clear
whether `CHECK' should mean `assert' or `forbid'.

In article <1752@tuvie> hp@vmars.tuwien.ac.at (Peter Holzer) writes:
>Karl obviously interpreted it the same way [as a `forbid' macro]

I noticed that the `||' version had the `assert' semantics, which I retained
in my second example (which I actually wrote first), assuming this was the
intent.  I then wrote the `?:' version while looking at the `if' version of
the original.  I even checked it against the copy in <assert.h>, noting that
the operands were in the opposite order, which I accepted because the `if'
version did indeed have the semantics of `forbid' rather than `assert'.  It
completely slipped my mind that I'd just made the opposite observation a
minute earlier!

>It is amazing though, that the Walking Lint missed the ||-&& confusion.

What I missed was that the two versions were inconsistent--I actually had the
right model for `a || b' in mind.

Karl W. Z. Heuer (karl@kelp.ima.isc.com or ima!kelp!karl), The Walking Lint