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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Difference between these pointer syntaxes
Date: Thu, 18 Aug 2016 13:22:52 -0700
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Les Cargill <lcargill99@comcast.com> writes:
> Keith Thompson wrote:
[...]
>> But the "arrays are really pointers" misconception is a *bad*
>> abstraction.
>>
>> Perhaps the worst problem with it (and I blame the design of C for this)
>> is that you can do a lot of stuff based on the assumption that arrays
>> and pointers are interchangeable.  But sooner or later you'll run into
>> things that can't be explained under that model.  `sizeof array_object`
>> yields the size of *something*, but what exactly, if there's no such
>> thing as an array?  If `ptr = array;` is valid, then `ptr = &array;`
>> is a compile-time error -- but why?
>>
>
> But we all understand ( after a learning period ) that "sizeof()"
> information is lost.

And I understand *when and why* it's lost -- but only because I
clearly distinguish between arrays and pointers.

[...]

>>>> Can you explain the behavior of `sizeof` while pretending that there's
>>>> no such thing as an array?  (Array type, array object, array whatever.)
>>>>
>>>> Can you explain what
>>>>
>>>>       int arr[10];
>>>>
>>>> does in terms of pointers, without references to arrays?  Can you
>>>> explain the result of `sizeof arr`?

[SNIP]

>> Sorry, that didn't help at all.  Can you explain it in terms of the
>> specific example I used?
>>
>>      int arr[10];
>>
>
> Sure!
>
> alternate declaration 1:
>
> int arr[] = static_allocate(10,); // no initial values.
>
> alternate declaration 2:
>
> int *arr = static_allocate(10,); // no initial values.
>
> The only difference then between them is that
> "arr = <anything>" is a diagnostic.

I asked you to explain the result of `sizeof arr`.  I don't see how your
static_allocate() thingie (not sure what it is) helps with that.

[...]

-- 
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"