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Date: Tue, 24 Sep 2019 02:05:44 -0700 (PDT)
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Subject: Implementing Rust's borrow checked pointers
From: Lucretia <laguest9000@googlemail.com>
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Xref: reader01.eternal-september.org comp.lang.ada:57177
Date: 2019-09-24T02:05:44-07:00
List-Id: <comp.lang.ada>

Hi,

Been talking to someone on Telegraph and he was saying Ada should implement this, just wondering whether Ada could? I posed a slight change to access type specification to do this, what do people think?

type P is restricted access X;

Restricted in this case would mean that once assigned it cannot be re-assigned into or out of with out some sort of move operation, which could be implemented as an attribute on the access type.

A : P := L'Access;
B : P := A'Move; --  A cannot no longer be used.

begin
   A.all ... ; -- raises exception.


I don't know enough about all this to put a complete proposal together, but I think I've got the basics understood.

Luke.