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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Deleting elements from a Vector
Date: Mon, 20 Apr 2015 12:13:30 +0100
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Date: 2015-04-20T12:13:30+01:00
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Georg Bauhaus <bauhaus@futureapps.invalid> writes:

> On 20.04.15 09:56, Simon Wright wrote:
>
>>>> Is there a proper idiom for doing this job? Should I maybe go over the
>>>> Vector in reverse order and use the version of Delete that uses the
>>>> index?
>>>
>>> Indeed that seems safer. Note also RM A.18.2(240/2..243/2) for the
>>> definition and properties of an "ambiguous" cursor. This also suggests
>>> traversing the vector in reverse index order.
>>
>> Like this:
>>
>>     for J in reverse 1 .. V.Last_Index loop
>>        if V (J) < 0 then
>>           Put_Line ("deleting element " & Integer'Image (V (J)));
>>           V.Delete (J);
>>        else
>>           Put_Line ("skipping element " & Integer'Image (V (J)));
>>        end if;
>>     end loop;
>
> +1; also, as this entails sliding, copying to a new vector and
> dumping the old seems another option that prevents any tampering.

Profiling needed! Thanks for the idea ...