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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Pointers, constant values
Date: Fri, 16 Oct 2015 12:06:22 -0700
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supercat@casperkitty.com writes:
> On Friday, October 16, 2015 at 10:25:16 AM UTC-5, Keith Thompson wrote:
>> Not everyone will agree with this; some will argue that using the []
>> notation is a reminder that it points to an element of an array, not
>> just a single int object.  Which is a valid point -- but in my opinion
>> the reminder that it's really a pointer is more valuable.
>
> How about, following along with the idea of "[static n]", how about adopting
> the convention of using "TYPE *name" in cases where the parameter might
> sometimes legitimately be null, and "TYPE name[]" in cases where the the
> parameter could never legitimately be null.  Using that convention...
>
>      void process_things(THING *things, int n);
>
> would suggest that process_things(NULL, 0); would do nothing, while
>
>      void process_things(THING things[], int n);
>
> would suggest that it must never be.
[...]

C already has a notation for asserting that a pointer parameter must be
non-null:

    void process_things(THING things[static 1], int n);

That's "asserting" in the sense that violating the assertion causes undefined
behavior.  Of course you can also add
    assert(things != NULL);
if you like, or treat it as a run-time error, or whatever.

-- 
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"