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From: david@csource.oz.au (david nugent)
Newsgroups: comp.lang.c
Subject: Re: TRUE and FALSE
Message-ID: <664@csource.oz.au>
Date: 27 Aug 90 19:44:54 GMT
References: <11215@alice.UUCP> <514@demott.COM>
Reply-To: david@csource.oz.au
Organization: Unique Computing Pty Ltd, Melb, Aust.
Lines: 46

In <514@demott.COM> kdq@demott.COM (Kevin D. Quitt) writes:

> >Unfortunately, using TRUE and FALSE opens a great gaping hole:
> >one would expect that
> >
> >	x == TRUE
> >
> >would mean the same as
> >
> >	x != FALSE
> >
> >but of course it doesn't -- at least not if you use the usual C
> >convention that 0 is false and any other value is true.

> We use 

> #define	TRUE	(1==1)
> #define	FALSE	(1!=1)

>     defined that way for hysterical raisins (broken compiler).  We are
> aware of the problem above, and never test booleans that way.  TRUE and
> FALSE are used for assignment purposes only.  It makes the intent of the
> code more obvious. 


Shouldn't

 # define FALSE 0
 # define TRUE  (!FALSE)
 
_always_ work?

I have been using this for a considerable amount of time, and so far
haven't seen any problems with it.  Or are there some circumstances
where this might not cover all cases?

Regards,

david


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