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Date: Sat, 14 Nov 2015 09:24:04 -0800 (PST)
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Subject: Re: A few questions
From: Shark8 <onewingedshark@gmail.com>
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Xref: news.eternal-september.org comp.lang.ada:28365
Date: 2015-11-14T09:24:04-08:00
List-Id: <comp.lang.ada>

On Saturday, November 14, 2015 at 5:37:32 AM UTC-7, Simon Wright wrote:
> 
> It's a pity that Next takes the iterator object as an 'in'
> parameter. This means that, in general, the cursor needs to hold the
> state. It certainly needs some way of indicating end-of-iteration;
> perhaps a sentinel value.

Sentinel values, or exceptions?
C-style strings use ASCII.NUL as a sentinel value, and look at the trouble that causes. (Of course part of that is due to the anemic idea of arrays that C has.)