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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: NULL as the empty string
Date: Sat, 09 Dec 2017 11:53:20 -0800
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jacobnavia <jacob@jacob.remcomp.fr> writes:
> Le 09/12/2017 à 02:47, Keith Thompson a écrit :
>> Would it be more convenient to treat a floating-point NaN as equivalent
>> to 0.0?  
[...]
> What is your point here? We are talking about strings, not floating 
> point numbers. I just made a comparison between a representation of 
> something that is a special value (NAN or inf) and the representation of 
> the empty string, that could be the NULL pointer.

My point is that in floating-point we have a clear and useful
distinction between a "null" value, 0.0, and a representation that
isn't a numeric value, NaN.

For char*, we have a clear distinction between a pointer to an
empty string and a pointer that doesn't point to a string at all.
They're logically quite distinct, and in my opinion it's a very
useful distinction.

I concede that it's not a very compelling point.  Still, I don't
think treating a null pointer as if it were a pointer to an empty
string is a good idea.  It's not a *horrible* idea, and if it were
added to a future standard I'd accept it with a little grumbling.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"