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From: Ben Bacarisse <ben@bsb.me.uk>
Newsgroups: comp.lang.c
Subject: Re: question about nullptr
Date: Thu, 11 Jul 2024 00:25:42 +0100
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Janis Papanagnou <janis_papanagnou+ng@hotmail.com> writes:

> On 09.07.2024 00:55, Ben Bacarisse wrote:
>> Janis Papanagnou <janis_papanagnou+ng@hotmail.com> writes:
>> 
>>> On 08.07.2024 18:23, Ben Bacarisse wrote:
>>>> Janis Papanagnou <janis_papanagnou+ng@hotmail.com> writes:
>>>>
>>>>> On 08.07.2024 12:18, Ben Bacarisse wrote:
>>>>>> Janis Papanagnou <janis_papanagnou+ng@hotmail.com> writes:
>>>>>>>
>>>>>>> What's superfluous to one is useful for others (e.g. for grep'ing
>>>>>>> occurrences of a null-pointer value in source codes);
>>>>>>
>>>>>> This is been suggested twice now but I'm struggling to see why that is
>>>>>> useful.  I can see management wanting one to find all uses of a null
>>>>>> pointer constant to check that they have all been replaced by the
>>>>>> "safer" nullptr, but what's the value in searching for nullptr?
>>>>>
>>>>> Bug-tracking.
>>>>
>>>> Can you say more?
>>>
>>> Frankly, no. [...]
>> 
>> OK.
>
> So the text you snipped from my reply did not trigger any insight?

I didn't read it.  You said you could not say more so I assumed what
you'd written was not saying more but something else like repeating what
you'd already said.

> Another, last try...
> Compare it to 'enum' constants. When I code or debug I want to track
> (search and find) them by name not by integer number.
> Similar with the 'enum' bool type we introduced (when there was not
> yet a bool type existing in C or C++) with literal constants 'true'
> and 'false'. (Only two values, but still as important.)
> Similar with the dedicated pointer value 0 (these days we used the
> literal 'null'). (Only one value, still useful for tracking eq/ne
> comparisons and initializations.)

Yes, you've said that before.  You want to search for nullptr.  I can't
think of how that might help find a real bug, if that's what you mean by
bug-tracking.

I was hoping for a story... "Once I had this bug where... and if I'd
been using nullptr I'd have found it a day earlier" kind of thing.  I'd
found a lot of bugs over the years, but I don't recall any that would
have been easier to find had I been able to search for nullptr.

I was looking for real-world insight here.  Obviously one could make up
a bug where p = nullptr; was written where, say, p = null - ptr; was
intended, but that's not what I mean.

Without such an example, your argument seems to be overly generic.
Would you welcome the introduction of the keyword unity -- with the
value 1 and type int -- into C because one could then search for it?

-- 
Ben.