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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: AI12-0218: What is the portable representation clause for
 processing IETF packets on little-endian machines?
Date: Fri, 11 May 2018 18:11:59 +0200
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Date: 2018-05-11T18:11:59+02:00
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On 05/11/2018 03:49 PM, Simon Wright wrote:
> Lucretia <laguest9000@googlemail.com> writes:
> 
>> On Friday, 11 May 2018 08:55:28 UTC+1, Simon Wright  wrote:
>>> In the body,
>>>
>>>     Big_Endian : constant Boolean
>>>       := System."=" (System.Default_Bit_Order, System.High_Order_First);
>>>
>>
>> Is it not possible to use derived types with different rep clauses to
>> implement byte swapping on assignment, like the pack/unpack trick can?
> 
> Maybe nowadays; not when that code was written.

You can, and have been able to since Ada 83.

-- 
Jeff Carter
"C++: The power, elegance and simplicity of a hand grenade."
Ole-Hjalmar Kristensen
90