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From: Brian Drummond <brian@shapes.demon.co.uk>
Newsgroups: comp.lang.ada
Subject: Re: asynchronous task communication
Date: Tue, 8 Jan 2013 12:02:52 +0000 (UTC)
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Date: 2013-01-08T12:02:52+00:00
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On Mon, 07 Jan 2013 11:27:20 -0700, Jeffrey Carter wrote:

> On 01/07/2013 03:49 AM, Brian Drummond wrote:
>>
>> Then how do you maintain links from one such object to others, to build
>> a network or graph? You can access a vector element via a cursor - is
>> it safe and reasonable to store and use cursors to maintain references
>> to an object as the vector grows?
> 
> A "vector" is an unbounded array. You access an array component using an
> index,
> and that is also how to reference a component of an unbounded array. The
> index of a specific component will not change unless the user
> specifically changes it (by inserting a component with a smaller index,
> for example).

And the index is a Cursor type.

So, holding onto a cursor would be unsafe (i.e. no longer refer to the 
original object) after an "insert" operation, possibly earlier in the 
vector?

- Brian