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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Community Input for the Maintenance and Revision of the Ada
 Programming Language
Date: Mon, 11 Sep 2017 21:33:08 +0200
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Date: 2017-09-11T21:33:08+02:00
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On 2017-09-11 20:49, Tarjei Jensen wrote:
> It is time to get counted strings into the standard.

There is no use for specifically reference-counted strings because 
strings are practically never assigned as a whole in properly written 
programs.

There are Unbounded_Strings to have dynamically-bound strings, which is 
not quite same as reference-counted ones, though I see no reason why an 
implementation of it cannot be reference-counted.

> The key to counted strings is that they need to be first class
> objects. The compiler must know how to handle them.

The use-case for reference-counted strings, if there is any then for 
concurrent access. This would require a lot of locking when handling the 
reference count and a lot of copying in order to clone concurrently 
written string body.

> I strongly believe that implementing it as a general Ada feature will be ineffective.

Any general purpose implementation of will be, see above.

For single task access existing string types are sufficient.

> I know that it will be tempting to do so, but RESIST!!!!!!

Why? It is quite trivial.

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