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From: "Dmitriy Anisimkov" <anisimkov@yahoo.com>
Newsgroups: comp.lang.ada
Subject: Re: GCC 4.0 Ada.Containers Cursor danger.
Date: 4 Jul 2005 21:27:35 -0700
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<<"A Cursor value is *invalid* if any of the following have occurred
since it was
created:
  ...
  * The node it designates has been deleted from the map." >>

Sure i understand that cursor become invalid. If the danger is written
in RM it is not become less danger.

<<Should access types not be in Ada?>>

Should be, because we could not make access to be invalid other then to
do *Unchecked_Deallocation* on it. Cursors could become invalid a much
more easier. I think access types in Ada safer than cursors in proposed
Ada.Containers.

<<Why are you using two different cursors (pointers),
then delete their element (set the pointee to null)>>

Because it is just example. Real code was different, and mistake was
made by the different person, i just found the error.
----------------------------
Table.Insert (Container, "two", 2222, Cursor, Success);

if not Success then
   Some_Package.Delete_From_Container (Key => "two");
end if;

Table.Replace_Element (Cursor, -22222); 
--------------------