From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on
	ip-172-31-74-118.ec2.internal
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=3.0 tests=BAYES_00 autolearn=ham
	autolearn_force=no version=3.4.4
Path: eternal-september.org!reader01.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED.2uCIJahv+a4XEBqttj5Vkw.user.gioia.aioe.org!not-for-mail
From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: General circular buffer example not tied to any specific type
Date: Sat, 4 Jul 2020 19:25:22 +0200
Organization: Aioe.org NNTP Server
Message-ID: <rdqe1v$dts$1@gioia.aioe.org>
References: <6ca9747e-698f-4d60-8e23-b883da5d9f38o@googlegroups.com>
NNTP-Posting-Host: 2uCIJahv+a4XEBqttj5Vkw.user.gioia.aioe.org
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit
X-Complaints-To: abuse@aioe.org
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101
 Thunderbird/68.10.0
X-Notice: Filtered by postfilter v. 0.9.2
Content-Language: en-US
Xref: reader01.eternal-september.org comp.lang.ada:59338
List-Id: <comp.lang.ada>

On 04/07/2020 19:00, Daniel wrote:

> I'm looking for any example of ravenscar buffer able for using any type of data at the same time.
> 
> I suppose it will need to serialize all  data and manipulate it as a group of bytes.
> 
> Does any body knows any example of this written in Ada?

Ring buffer of indefinite elements would be OK. As an element you can 
use this:

    type Item (Size : Stream_Element_Count) is record
        Data : Stream_Element_Array (1..Size);
    end record;

Instantiate the generic buffer with this type. Use stream attributes to 
serialize/deserialize.

Alternatively you can do it with Storage_Element in the above and use a 
fake storage pool to store/restore objects. Or a combination "for 
X'Address use Y" with pragma Import (Ada, X);

If the type set is somewhat statically known you can use a variant 
record as an element too.

In some cases you can have a ring buffer of type tags and a set of ring 
buffers. For each type tag you would keep values in a separate ring buffer.

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