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From: Kaz Kylheku <643-408-1753@kylheku.com>
Newsgroups: comp.lang.c
Subject: Re: Code guidelines
Date: Tue, 1 Oct 2024 21:39:21 -0000 (UTC)
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On 2024-10-01, Vir Campestris <vir.campestris@invalid.invalid> wrote:
> On 03/09/2024 17:23, Thiago Adams wrote:
><snip>
>> but...maybe, is better to be a little redundant here?
>> I think I prefer to leave "obj->member1->member2 && " even if I know
>> it should not be null.
>> 
>> if (obj->member1 &&
>>      obj->member1->member2 &&
>>      obj->member1->member2->member3)
>> {
>> 
>> }
>
> I think I'd prefer to _omit_ the check that obj->member1->member2 isn't 
> null.
>
> If the code is running correctly that check will never trigger, and is 
> redundant, and will slow things slightly.

How about:

  #define vassert(x) (assert(x), 1)

  if (obj->member1 &&
      vassert(obj->member1->member2) &&
      obj->member1->member2->member3)

If NDEBUG is defined, that just reduces to 1, and is optimized
away. If NDEBUG is absent, the null pointer crash is replaced
by an assertion failure.

-- 
TXR Programming Language: http://nongnu.org/txr
Cygnal: Cygwin Native Application Library: http://kylheku.com/cygnal
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