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Date: Tue, 25 Apr 2023 00:30:37 -0700 (PDT)
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Subject: Re: strange cursor in nested containers
From: Mario Blunk <mario.blunk.gplus@gmail.com>
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Xref: news.eternal-september.org comp.lang.ada:65136
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> > How could I solve the problem ? Not using "rename" ? Using an aliased access type as John Barnes suggests in Ada2005 on page 275 ?
> You have to avoid calling Element. Since you have a cursor, you can call 
> Query_Element, which should pass the actual element to the procedure you supply. 

Right, that solves the problem. For those interested please find a comparison here:

1. The demo with a dangling (dangerous) cursor:
https://github.com/Blunk-electronic/ada_training/blob/master/src/containers/demo/nested/nest_1.adb

And the demo with the issue solved properly:
https://github.com/Blunk-electronic/ada_training/blob/master/src/containers/demo/nested/nest_2.adb

Still the question remains, why such a dangling cursor is not detected at runtime.