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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Map iteration and modification
Date: Thu, 28 Dec 2023 21:08:47 -0600
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"DrPi" <314@drpi.fr> wrote in message 
news:umjuvc$9sp$2@rasp.pasdenom.info...
> 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 ?

If the keys are messy to save (as say with type String), it might be easier 
to save the cursor(s) of the nodes to delete. You would probably want to use 
a cursor iterator (that is, "in") to get the cursors. Code would be 
something like (declarations of the Map and List not shown, nor is the 
function Need_to_Delete which is obviously application specific, Save_List 
is a list of cursors for My_Map, everything else is standard, not checked 
for syntax errors):

    Save_List.Empty; -- Clear list of saved cursors.
    -- Find the nodes of My_Map that we don't need.
    for C in My_Map.Iterate loop
       if Need_to_Delete (My_Map.Element(C)) then
            Save_List.Append (C);
       -- else no need to do anything.
      end if;
   end loop;
   -- Delete the cursors of the nodes we don't want anymore.
   for C of Save_List loop
       My_Map.Delete(C);
   end loop;



                    Randy.