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From: Simon Wright <simon@pushface.org>
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Subject: Re: Stream_Element_Array
Date: Wed, 14 Sep 2011 11:53:13 +0100
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> P.S. Do not use representation clauses or unchecked conversion, I *do*
> mean it:

I would of course agree if the data type didn't occupy the full width of
the buffer it was being converted into. I suppose that can happen quite
frequently? (I took OP's "Unsigned_16" to mean a 16-bit wide type).

Shouldn't be a similar problem with endianness conversions, though.

> P.P.S. Stream element might be not the best choice if you are
> communicating with the external world. You could also consider taking
> Unsigned_8 and an array built upon it, because in most cases the
> hardware talks in octets.  That does not change the pattern, of
> course.

I know the RM doesn't specify this, and goes out of its way to allow
9-bit bytes and 36-bit storage units. But how many real-life situations
are there where Stream_Element'Size isn't 8?

Of course, if your hardware registers are 16 or 32 bits wide, that's a
different ballgame.