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Re: 64-bit bytes

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On 12/01/2015 18:11, Dmitry A. Kazakov wrote:
> On Mon, 12 Jan 2015 17:42:42 +0000, BartC wrote:

>> println int.bytes
>> println byte.bytes
>> println bit.bytes
>>
>> I get: 4, 1 and 1. But if I write:
>>
>> println int.bitwidth
>> println byte.bitwidth
>> println bit.bitwidth
>>
>> Then I get 32, 8 and 1.
>
> Which is evidently inconsistent with your definition of byte = 8 * bits.

Not with the last lot of bit-widths.

>> If you created a function in Ada to return the size of a type in terms
>> of 8-bit bytes, and the result had to be an integer, then you will get
>> similar problems.
>
> That would be Float (T'Size)/8.0 without rounding and (T'Size+7)/8 with
> rounding. Except that usefulness of such functions is questionable.
>
> When you write a custom storage pool in Ada, the compiler passes the
> required number of storage elements (note, not bits nor bytes) to your
> implementation of Allocate.
>
> 8 bits
> 1 byte
> 1 Storage_Element
>
> are potentially all different.

So? I can write this:

a := new(array, bit, -41..75)

This yields bounds of (-41,75), and a length of 117 /bits/. It is 
possible to work with bits, bit-fields and bit-arrays without worrying 
about bytes (although the byte size of that array if I was interested 
would be 15 bytes rather than 14.625).

So it's possible work with bits within software even though the 
underlying machine is byte-oriented, as most are. It's just not 
necessary to work exclusively with bits as you are suggesting.

And the same byte-oriented approach is used with memory and storage 
devices, even though the underlying hardware /is/ bit-oriented!

-- 
Bartc

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64-bit bytes fir <profesor.fir@gmail.com> - 2015-01-05 01:38 -0800
  Re: 64-bit bytes robin.vowels@gmail.com - 2015-01-08 00:46 -0800
    Re: 64-bit bytes fir <profesor.fir@gmail.com> - 2015-01-08 00:53 -0800
      Re: 64-bit bytes robin.vowels@gmail.com - 2015-01-11 15:46 -0800
        Re: 64-bit bytes Richard Heathfield <invalid@see.sig.invalid> - 2015-01-12 00:32 +0000
          Re: 64-bit bytes BartC <bc@freeuk.com> - 2015-01-12 01:35 +0000
            Re: 64-bit bytes Richard Heathfield <invalid@see.sig.invalid> - 2015-01-12 09:07 +0000
              Re: 64-bit bytes BartC <bc@freeuk.com> - 2015-01-12 11:43 +0000
                Re: 64-bit bytes Richard Heathfield <invalid@see.sig.invalid> - 2015-01-12 11:59 +0000
                Re: 64-bit bytes BartC <bc@freeuk.com> - 2015-01-12 12:21 +0000
                Re: 64-bit bytes Mark Carroll <mtbc@bcs.org> - 2015-01-12 12:36 +0000
                Re: 64-bit bytes Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-01-12 14:15 +0000
                Re: 64-bit bytes BartC <bc@freeuk.com> - 2015-01-12 14:34 +0000
                Re: 64-bit bytes "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-01-12 16:35 +0100
                Re: 64-bit bytes BartC <bc@freeuk.com> - 2015-01-12 17:42 +0000
                Re: 64-bit bytes "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-01-12 19:11 +0100
                Re: 64-bit bytes BartC <bc@freeuk.com> - 2015-01-12 19:18 +0000
                Re: 64-bit bytes "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-01-12 21:34 +0100
                Re: 64-bit bytes BartC <bc@freeuk.com> - 2015-01-12 22:01 +0000
                Re: 64-bit bytes Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-01-13 00:51 +0000
                Re: 64-bit bytes Richard Heathfield <invalid@see.sig.invalid> - 2015-01-12 13:18 +0000
                Re: 64-bit bytes BartC <bc@freeuk.com> - 2015-01-12 14:16 +0000
                Re: 64-bit bytes Richard Heathfield <invalid@see.sig.invalid> - 2015-01-12 14:48 +0000
                Re: 64-bit bytes BartC <bc@freeuk.com> - 2015-01-12 15:05 +0000
                Re: 64-bit bytes Robert Wessel <robertwessel2@yahoo.com> - 2015-01-12 15:43 -0600
              Re: 64-bit bytes Kaz Kylheku <kaz@kylheku.com> - 2015-01-12 21:05 +0000
                Re: 64-bit bytes Richard Heathfield <invalid@see.sig.invalid> - 2015-01-12 22:12 +0000
            Re: 64-bit bytes "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-01-12 10:12 +0100
          Re: 64-bit bytes robin.vowels@gmail.com - 2015-01-11 20:56 -0800
            Re: 64-bit bytes Richard Heathfield <invalid@see.sig.invalid> - 2015-01-12 09:19 +0000
              Re: 64-bit bytes robin.vowels@gmail.com - 2015-01-12 06:22 -0800
                Re: 64-bit bytes Richard Heathfield <invalid@see.sig.invalid> - 2015-01-12 14:51 +0000
                Re: 64-bit bytes robin.vowels@gmail.com - 2015-01-12 15:46 -0800
                Re: 64-bit bytes Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-01-13 01:16 +0000
                Re: 64-bit bytes Richard Heathfield <invalid@see.sig.invalid> - 2015-01-13 01:53 +0000
                Re: 64-bit bytes Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-01-13 13:28 +0000
                Re: 64-bit bytes Richard Heathfield <invalid@see.sig.invalid> - 2015-01-13 13:57 +0000
                Re: 64-bit bytes "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-01-13 15:32 +0100
                Re: 64-bit bytes fir <profesor.fir@gmail.com> - 2015-01-13 06:33 -0800
                Re: 64-bit bytes BartC <bc@freeuk.com> - 2015-01-13 16:41 +0000
                Re: 64-bit bytes fir <profesor.fir@gmail.com> - 2015-01-13 15:25 -0800
                Re: 64-bit bytes BartC <bc@freeuk.com> - 2015-01-13 23:49 +0000
                Re: 64-bit bytes fir <profesor.fir@gmail.com> - 2015-01-13 23:57 -0800

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