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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Map iteration and modification
Date: Thu, 28 Dec 2023 17:06:20 +0100
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On 2023-12-28 14:59, DrPi wrote:
> Le 28/12/2023 à 14:53, DrPi a écrit :
>> Iterate the Map and temporarily store the key nodes to be deleted then 
>> delete the nodes from the key list ?
> 
> Not clear. Rephrasing it.
> Using 2 steps by iterating the Map and temporarily store the keys of 
> nodes to be deleted then delete the Map nodes using the key list ?

[Disclaimer. I am not talking about the standard library]

Provided a sane implementation of map.

1. It is safe to loop over the map items in the *reverse* order of, 
deleting whatever items.

2. It is safe to walk whatever set of map keys, deleting items of the map.

In both cases #1 positions, #2 keys are invariant to the operation of 
deletion.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de