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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: absence of max
Date: Mon, 28 Nov 2016 23:23:03 -0800
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BartC <bc@freeuk.com> writes:
> On 29/11/2016 00:14, Ben Bacarisse wrote:
>> BartC <bc@freeuk.com> writes:
>> <snip>
>>> C allows this:
>>>
>>>   char* s = "Hello world";
>>>   int n = 5;
>>>
>>>   printf("%s\n", s + n);
>>>   printf("%d\n", s + n);
>>>   printf("%p\n", s + n);
>>>
>>> So it can add a number to a string
>>
>> No it can't.
>
> Yes it can; that's what the code is doing.
>
> s is used to refer to a string.

Yes, s is used to refer to a string.  s is not a string.  s is a
pointer.  You understand that, but you spread confusion by pretending
not to.  Stop it.

> n is a number.

Yup.  (More precisely an integer, even more precisely an object of type
int).

> The language allows you to add those together using 's + n'.

Yes, you can add a pointer and an integer, with semantics that have been
discussed at length.

> Of course the actual operation it does, because of how C works, is not 
> very interesting: it takes the address of the start of the string, and 
> steps it by 5. It doesn't end up with "Hello world5" or, after trying to 
> convert "Hello World" to number and getting 0, adding 5 to that.

Oh?  I'd call it very interesting.  It's at the core of how C deals with
arrays and their elements.  Of course you pretend not to understand that
because it helps you spread confusion.

> But then exactly what 'add number to a string' does hasn't been defined.

No, it hasn't, because it doesn't make any sense.  Please stop making
things up.  C can be confusing enough.  Stop trying to make it worse.

[...]

-- 
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"