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From: Georg Bauhaus <bauhaus@futureapps.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Deleting elements from a Vector
Date: Mon, 20 Apr 2015 10:39:07 +0200
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Date: 2015-04-20T10:39:07+02:00
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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.