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"Malcolm McLean" <> writes:
> "user923005" <> wrote in message
>
>> #define TRUE 1 #define YES 1
>> #define FALSE 0 #define NO 0
>
>> #define TRUE -1 is also very neat.

It would have to be
#define TRUE (-1)

> A single set bit is -1 in two's complement notation, but the real
> advantage is now we can say
> ~TRUE == FALSE.

-1 has *all* bits set, not a single bit. And I fail to see the
advantage of ~TRUE == FALSE. Surely !TRUE == FALSE is better.

Define TRUE and FALSE as 1 and 0 also matches the results of the
equality and relational operators (though of course any non-zero value
is true).

--
Keith Thompson (The_Other_Keith) <kst->
[...]
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

On Dec 28, 5:39 pm, Chris McDonald <ch...@csse.uwa.edu.au> wrote:
> Ivan Novick <i...@0x4849.net> writes:
> >If you are trying to get existing code to compile and don't have bool
> >on your system try typedefing it.
> >typedef short bool
> >#define true 1
> >#define false 0
>
> (Serious question) why have you chosen to use a short (not a char, not an int)?
> Thanks,
>
> --
> Chris.

I agree, it should be char.

Regards,
Ivan Novick
http://www.0x4849.net

Malcolm McLean wrote:

> "user923005" <> wrote in message
>
>> #define TRUE 1 #define YES 1
>> #define FALSE 0 #define NO 0
>
>> #define TRUE -1 is also very neat.
Why did you precede that line by >? it was not in the post you were
replying to. Btw, I'd add parentheses, just to avoid... er... TRUE[ptr]
do the wrong thing.

> A single set bit is -1 in two's complement notation, but the real advantage
> is now we can say
> ~TRUE == FALSE.
I fail to see why that's an advantage.
--
Army1987 (Replace "NOSPAM" with "email")

Army1987 wrote:
> Malcolm McLean wrote:
>
>> "user923005" <> wrote in message
>>
>>> #define TRUE 1 #define YES 1
>>> #define FALSE 0 #define NO 0
>>> #define TRUE -1 is also very neat.
> Why did you precede that line by >? it was not in the post you were

Your newsreader must have missed a message

Army1987 wrote, On 29/12/07 15:30:
> Malcolm McLean wrote:
>
>> "user923005" <> wrote in message
>>
>>> #define TRUE 1 #define YES 1
>>> #define FALSE 0 #define NO 0
>>> #define TRUE -1 is also very neat.
> Why did you precede that line by >? it was not in the post you were
> replying to. Btw, I'd add parentheses, just to avoid... er... TRUE[ptr]
> do the wrong thing.

Indeed.

>> A single set bit is -1 in two's complement notation, but the real advantage
>> is now we can say
>> ~TRUE == FALSE.
> I fail to see why that's an advantage.

Once upon a time in a land far far away there existed processors where
it made sense to use -1 for one of the two logical values. Well, the
land was not very far away, but processors have been able to do
efficient comparisons against 0 for a very long time, so it really was
long long ago.

Of course, as I said earlier comparing against TRUE is a very dangerou
thing to do. Doing it with TRUE defined as -1 is more dangerous because
the expressions ((1==1)==TRUE) would yield 0, i.e. false. So we have the
following:

if ((1==1) == TRUE)
puts("Not completely broken definition of TRUE");
else
puts("A completely broken definition of TRUE");

Will correctly report "A completely broken definition of TRUE".
--
Flash Gordon

Golden California Girls <> writes:
> Army1987 wrote:
>> Malcolm McLean wrote:
>>
>>> "user923005" <> wrote in message
>>>
>>>> #define TRUE 1 #define YES 1
>>>> #define FALSE 0 #define NO 0
>>>> #define TRUE -1 is also very neat.
>> Why did you precede that line by >? it was not in the post you were
>
> Your newsreader must have missed a message

No, I just checked. The lines

#define TRUE 1 #define YES 1
#define FALSE 0 #define NO 0

were in user923005's message (quoted from the FAQ); the line

#define TRUE -1 is also very neat.

was not; it first appeared in Malcolm's message with a ">" prefix.

--
Keith Thompson (The_Other_Keith) <kst->
[...]
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

Golden California Girls wrote:

> Army1987 wrote:
>> Malcolm McLean wrote:
>>
>>> "user923005" <> wrote in message
>>>
>>>> #define TRUE 1 #define YES 1
>>>> #define FALSE 0 #define NO 0
>>>> #define TRUE -1 is also very neat.
>> Why did you precede that line by >? it was not in the post you were
>
> Your newsreader must have missed a message
Even if it has, someone used a wrong number of > signs.
The lines " #define TRUE 1 #define YES 1" and "#define TRUE -1 is ..."
appear to be both by user923005, whose message I have, but the latter line
doesn't appear there.


--
Army1987 (Replace "NOSPAM" with "email")

Army1987 wrote:
> Golden California Girls wrote:
>
>> Army1987 wrote:
>>> Malcolm McLean wrote:
>>>
>>>> "user923005" <> wrote in message
>>>>
>>>>> #define TRUE 1 #define YES 1
>>>>> #define FALSE 0 #define NO 0
>>>>> #define TRUE -1 is also very neat.
>>> Why did you precede that line by >? it was not in the post you were
>> Your newsreader must have missed a message
> Even if it has, someone used a wrong number of > signs.
> The lines " #define TRUE 1 #define YES 1" and "#define TRUE -1 is ..."
> appear to be both by user923005, whose message I have, but the latter line
> doesn't appear there.

It appears as if Malcolm started his response with a ">" character. Likely was
on the wrong line when he typed it. My newsreader does have a blank line
between his response and the quoted material above.

Golden California Girls wrote:

> Army1987 wrote:
>> Golden California Girls wrote:
>>
>>> Army1987 wrote:
>>>> Malcolm McLean wrote:
>>>>>> #define TRUE -1 is also very neat.
>>>> Why did you precede that line by >? it was not in the post you were
>>> Your newsreader must have missed a message
>> Even if it has, someone used a wrong number of > signs.
>> The lines " #define TRUE 1 #define YES 1" and "#define TRUE -1 is ..."
>> appear to be both by user923005, whose message I have, but the latter line
>> doesn't appear there.
>
> It appears as if Malcolm started his response with a ">" character. Likely was
> on the wrong line when he typed it. My newsreader does have a blank line
> between his response and the quoted material above.

And what I asked to Malcom was exactly why did he add a > at the beginning
of the line.

--
Army1987 (Replace "NOSPAM" with "email")

On Tue, 1 Jan 2008 11:06:17 -0600, Army1987 wrote
(in article <fldru9$tpn$>):

> Golden California Girls wrote:
>
>> Army1987 wrote:
>>> Golden California Girls wrote:
>>>
>>>> Army1987 wrote:
>>>>> Malcolm McLean wrote:
>>>>>>> #define TRUE -1 is also very neat.
>>>>> Why did you precede that line by >? it was not in the post you were
>>>> Your newsreader must have missed a message
>>> Even if it has, someone used a wrong number of > signs.
>>> The lines " #define TRUE 1 #define YES 1" and "#define TRUE -1 is ..."
>>> appear to be both by user923005, whose message I have, but the latter line
>>> doesn't appear there.
>>
>> It appears as if Malcolm started his response with a ">" character. Likely
>> was
>> on the wrong line when he typed it. My newsreader does have a blank line
>> between his response and the quoted material above.
>
> And what I asked to Malcom was exactly why did he add a > at the beginning
> of the line.

In the spirit of those "making mountains out of molehills", have you
all really never made a simple typo when editing a response to a long
threaded post with lots of different levels of '>>>>' indentation?

It happens. Furrfu.


--
Randy Howard (2reply remove FOOBAR)
"The power of accurate observation is called cynicism by those
who have not got it." - George Bernard Shaw