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Subject: Re: [PATCH 2/3] dynarray: Implement remove function
To: Alexander Monakov <amonakov@ispras.ru>
Cc: libc-alpha@sourceware.org
References: <1518008967-8310-1-git-send-email-adhemerval.zanella@linaro.org>
 <1518008967-8310-2-git-send-email-adhemerval.zanella@linaro.org>
 <alpine.LNX.2.20.13.1802071744380.25773@monopod.intra.ispras.ru>
From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Message-ID: <f54369de-8bd1-4ed1-b5a0-dadc860bedba@linaro.org>
Date: Wed, 07 Feb 2018 17:16:00 -0000
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On 07/02/2018 12:48, Alexander Monakov wrote:
> On Wed, 7 Feb 2018, Adhemerval Zanella wrote:
> 
>> This patch implements the remove item function for dynarray array.
>> It is a costly operation, since it requires a memory move operation
>> possible as large as the array size less one element.
> 
> If preserving order is not required, then removing an element is as
> cheap as moving only the last element to the position of the removed.
> 
> If order preservation, is, in fact, part of the intended interface,
> then shouldn't the new function be named like '..._ordered_remove'
> to reflect that?
> 
> Alexander
> 

I see dynarray works similar to c++ vector container and the remove
usage on subsequent patch expects order preservation.  So I would
prefer to use the other way around your suggestion: to add a
unordered_remove if the case.