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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: Two different Results between C and C++
Date: Tue, 02 Jun 2020 11:51:54 -0700
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Lew Pitcher <lew.pitcher@digitalfreehold.ca> writes:
> On June 2, 2020 12:26, Keith Thompson wrote:
>> mark.bluemel@gmail.com writes:
>> [...]
>>> (1!=1) is a C boolean value, which is an int.
>> 
>> Not exactly.  C does have a boolean type, called _Bool (or bool if
>> you've included <stdbool.h>.  But equality and comparison operators
>> yield values of type int, not of type bool.
>
> I believe that Mark was trying to indicate the distinction between how C++ 
> interprets (1!=1) and how C interprets it.
>
> In the C++ case, (1!=1) results in a boolean type, holding a boolean value 
> (or so Mark implies; I don't know C++)
>
> In the C case, (1~=1) results in an int type (which Mark does point out), 
> holding value that indicates the truth or falsehood of the assertion (a 
> "boolean" value).
>
> Perhaps Mark will clarify his post for us.

Yes, what Mark said is mostly correct.  My quibble is about the
phrase "C boolean value".  I suppose you could say that 0 (of type
int) is a "C boolean value", but it would make more sense to apply
that term to a value of the C type _Bool.

In C90, where _Bool didn't yet exist, I wouldn't have much of a
problem referring to 0 as a "C boolean value".

And just to add to the frivolity, the macros "false" and "true"
in <stdbool.h> expand to 0 and 1, respectively, which are of type
_Bool, not int.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Philips Healthcare
void Void(void) { Void(); } /* The recursive call of the void */