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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: size_t best practice
Date: Thu, 22 Aug 2024 06:12:53 -0700
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Ike Naar <ike@sdf.org> writes:

> On 2024-08-22, Tim Rentsch <tr.17687@z991.linuxsc.com> wrote:
>
>> Andrey Tarasevich <andreytarasevich@hotmail.com> writes:
>>
>>> We can immediately apply the pattern I demonstrated above to this
>>> and get
>>>
>>>   for (size_t i = v->_size - 1; i != index - 1; --i)
>>>     v->_values[i + 1] = v->_values[i];
>>>
>>> Done.  No need for an extra safeguard.
>>
>> Better (please ignore cosmetic layout differences):
>>
>>     for( size_t i = v->_size;  i > index;  i--  ){
>>         v->_values[i] = v->_values[i-1];
>>     }
>
> Or even get rid of the for loop, and use memmove() :
>
>   memmove(v->_values + index + 1, v->_values + index,
>           (v->_size - index) * sizeof *v->_values);

Yes, although that ignores the context of the question
that was asked, about how to deal with loop index
variables in the presence of possible "underflow".