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Restricted unsigned integer range would have been better?

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  Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-23 01:32 -0600
    Re: Restricted unsigned integer range would have been better? "christian.bau" <christian.bau@cbau.wanadoo.co.uk> - 2012-07-23 01:45 -0700
      Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-24 00:19 -0600
        Re: Restricted unsigned integer range would have been better? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-07-24 11:25 +0100
          Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-24 16:22 -0600
            Re: Restricted unsigned integer range would have been better? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-07-25 01:53 +0100
              Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-24 21:43 -0600
        Re: Restricted unsigned integer range would have been better? "christian.bau" <christian.bau@cbau.wanadoo.co.uk> - 2012-07-24 16:29 -0700
          Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-24 21:53 -0600
            Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-07-24 23:24 -0700
              Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-25 01:12 -0600
    Re: Restricted unsigned integer range would have been better? Nobody <nobody@nowhere.com> - 2012-07-23 10:37 +0100
      Re: Restricted unsigned integer range would have been better? Andre <lodwig@pathme.de> - 2012-07-23 11:46 +0200
    Re: Restricted unsigned integer range would have been better? "BartC" <bc@freeuk.com> - 2012-07-23 11:33 +0100
      Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-23 23:48 -0600
        Re: Restricted unsigned integer range would have been better? "BartC" <bc@freeuk.com> - 2012-07-24 10:43 +0100
          Re: Restricted unsigned integer range would have been better? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-07-24 02:58 -0700
            Re: Restricted unsigned integer range would have been better? "BartC" <bc@freeuk.com> - 2012-07-24 12:04 +0100
              Re: Restricted unsigned integer range would have been better? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-07-24 05:32 -0700
                Re: Restricted unsigned integer range would have been better? "BartC" <bc@freeuk.com> - 2012-07-24 14:20 +0100
                  Re: Restricted unsigned integer range would have been better? "BartC" <bc@freeuk.com> - 2012-07-24 18:41 +0100
                  Re: Restricted unsigned integer range would have been better? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-07-24 12:37 -0700
              Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-24 16:15 -0600
          Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-24 16:05 -0600
            Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-07-24 23:28 -0700
              Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-25 01:13 -0600
                Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-07-25 01:26 -0700
                  Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-25 05:43 -0600
        Re: Restricted unsigned integer range would have been better? David Brown <david@westcontrol.removethisbit.com> - 2012-07-24 15:10 +0200
          Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-24 16:23 -0600
            Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-07-24 23:40 -0700
              Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-25 01:32 -0600
                Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-07-25 01:29 -0700
                  Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-25 05:45 -0600
                    Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-07-25 12:35 -0700
                      Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-26 00:12 -0600
                        Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-07-26 01:42 -0700
            Re: Restricted unsigned integer range would have been better? David Brown <david@westcontrol.removethisbit.com> - 2012-07-25 09:31 +0200
              Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-25 06:28 -0600
                Re: Restricted unsigned integer range would have been better? David Brown <david@westcontrol.removethisbit.com> - 2012-07-25 16:28 +0200
                  Re: Restricted unsigned integer range would have been better? "BartC" <bc@freeuk.com> - 2012-07-25 17:17 +0100
                    Re: Restricted unsigned integer range would have been better? David Brown <david@westcontrol.removethisbit.com> - 2012-07-26 12:07 +0200
                      Re: Restricted unsigned integer range would have been better? "BartC" <bc@freeuk.com> - 2012-07-26 14:06 +0100
                        Re: Restricted unsigned integer range would have been better? James Kuyper <jameskuyper@verizon.net> - 2012-07-26 09:45 -0400
                        Re: Restricted unsigned integer range would have been better? David Brown <david@westcontrol.removethisbit.com> - 2012-07-30 09:01 +0200
                  Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-26 00:09 -0600
                    Re: Restricted unsigned integer range would have been better? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-07-26 00:52 -0700
    Re: Restricted unsigned integer range would have been better? pete <pfiland@mindspring.com> - 2012-07-26 20:35 -0400
      Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-26 22:35 -0600
        Re: Restricted unsigned integer range would have been better? pete <pfiland@mindspring.com> - 2012-07-27 09:19 -0400
          Re: Restricted unsigned integer range would have been better? Les Cargill <lcargill99@comcast.com> - 2012-07-27 12:51 -0500
            Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-07-27 16:19 -0700
              Re: Restricted unsigned integer range would have been better? Les Cargill <lcargill99@comcast.com> - 2012-07-27 18:47 -0500
                Re: Restricted unsigned integer range would have been better? David Brown <david@westcontrol.removethisbit.com> - 2012-07-30 09:10 +0200
                  Re: Restricted unsigned integer range would have been better? Philip Lantz <prl@canterey.us> - 2012-07-31 17:26 -1000
                    Re: Restricted unsigned integer range would have been better? pete <pfiland@mindspring.com> - 2012-08-01 00:18 -0400
                      Re: Restricted unsigned integer range would have been better? "io_x" <a@b.c.invalid> - 2012-08-01 10:19 +0200
                      Re: Restricted unsigned integer range would have been better? David Brown <david@westcontrol.removethisbit.com> - 2012-08-01 10:09 +0200
                        Re: Restricted unsigned integer range would have been better? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-01 12:51 +0100
                          Re: Restricted unsigned integer range would have been better? pete <pfiland@mindspring.com> - 2012-08-01 08:18 -0400
                            Re: Restricted unsigned integer range would have been better? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-01 14:22 +0100
                              Re: Restricted unsigned integer range would have been better? pete <pfiland@mindspring.com> - 2012-08-01 09:57 -0400
                                Re: Restricted unsigned integer range would have been better? pete <pfiland@mindspring.com> - 2012-08-01 11:35 -0400
                      Re: Restricted unsigned integer range would have been better? Tim Rentsch <txr@alumni.caltech.edu> - 2012-09-07 11:43 -0700
                        Re: Restricted unsigned integer range would have been better? pete <pfiland@mindspring.com> - 2012-09-08 10:13 -0400
                          Re: Restricted unsigned integer range would have been better? Philip Lantz <prl@canterey.us> - 2012-09-22 23:39 -0700
                            Re: Restricted unsigned integer range would have been better? Philip Lantz <prl@canterey.us> - 2012-09-22 23:45 -0700
                              Re: Restricted unsigned integer range would have been better? Tim Rentsch <txr@alumni.caltech.edu> - 2012-12-17 13:52 -0800
                            Re: Restricted unsigned integer range would have been better? Tim Rentsch <txr@alumni.caltech.edu> - 2012-12-17 13:45 -0800
                              Re: Restricted unsigned integer range would have been better? pete <pfiland@mindspring.com> - 2012-12-17 19:51 -0500
                              Re: Restricted unsigned integer range would have been better? Philip Lantz <prl@canterey.us> - 2012-12-28 11:11 -0800
                                Re: Restricted unsigned integer range would have been better? Tim Rentsch <txr@alumni.caltech.edu> - 2012-12-29 11:31 -0800
                                  Re: Restricted unsigned integer range would have been better? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2012-12-29 23:59 +0000
                                    Re: Restricted unsigned integer range would have been better? Tim Rentsch <txr@alumni.caltech.edu> - 2013-01-02 10:01 -0800
                                      Re: Restricted unsigned integer range would have been better? Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-01-05 12:00 +0200
                                  Re: Restricted unsigned integer range would have been better? Philip Lantz <prl@canterey.us> - 2013-01-02 13:07 -0800
                                    Re: Restricted unsigned integer range would have been better? Tim Rentsch <txr@alumni.caltech.edu> - 2013-01-03 12:10 -0800
                                    Re: Restricted unsigned integer range would have been better? James Kuyper <jameskuyper@verizon.net> - 2013-01-05 12:26 -0500
                        Re: Restricted unsigned integer range would have been better? Philip Lantz <prl@canterey.us> - 2012-09-22 23:35 -0700
                          Re: Restricted unsigned integer range would have been better? Tim Rentsch <txr@alumni.caltech.edu> - 2012-12-17 14:02 -0800
                    Re: Restricted unsigned integer range would have been better? David Brown <david@westcontrol.removethisbit.com> - 2012-08-01 10:06 +0200
                      Re: Restricted unsigned integer range would have been better? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-01 12:46 +0100
                        Re: Restricted unsigned integer range would have been better? Philip Lantz <prl@canterey.us> - 2012-08-02 08:19 -1000
                      Re: Restricted unsigned integer range would have been better? Philip Lantz <prl@canterey.us> - 2012-08-02 08:17 -1000
                        Re: Restricted unsigned integer range would have been better? David Brown <david@westcontrol.removethisbit.com> - 2012-08-03 08:04 +0200
                      Re: Restricted unsigned integer range would have been better? "io_x" <a@b.c.invalid> - 2012-08-03 09:40 +0200
              Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-27 22:27 -0600
                Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-07-28 01:31 -0700
                Re: Restricted unsigned integer range would have been better? "BartC" <bc@freeuk.com> - 2012-07-28 10:52 +0100
              Re: Restricted unsigned integer range would have been better? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-07-28 03:31 -0700
            Re: Restricted unsigned integer range would have been better? pete <pfiland@mindspring.com> - 2012-07-28 00:05 -0400
              Re: Restricted unsigned integer range would have been better? Les Cargill <lcargill99@comcast.com> - 2012-07-27 23:22 -0500
              Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-07-27 22:35 -0600
                Re: Restricted unsigned integer range would have been better? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-08-04 08:43 -0700
                  Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-08-04 16:40 -0700
                    Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-08-04 22:58 -0600
                      Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-08-04 23:10 -0700
                        Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-08-05 01:16 -0600
                          Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-08-05 02:25 -0700
                            Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-08-05 03:35 -0600
                              Re: Restricted unsigned integer range would have been better? Keith Thompson <kst-u@mib.org> - 2012-08-05 12:16 -0700
                                Re: Restricted unsigned integer range would have been better? gazelle@shell.xmission.com (Kenny McCormack) - 2012-08-05 19:56 +0000
                                  Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-08-06 01:12 -0600
                                Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-08-06 01:07 -0600
                        Re: Restricted unsigned integer range would have been better? gazelle@shell.xmission.com (Kenny McCormack) - 2012-08-05 13:33 +0000
                          Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-08-06 01:13 -0600
                  Re: Restricted unsigned integer range would have been better? "Ansel" <tinker454@trytospammenowloser.com> - 2012-08-04 22:54 -0600

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#23604 — Restricted unsigned integer range would have been better?

If C's unsigned integer types were designed so that their maximum value was
the same as the absolute value of the same width signed integer type's
minimum value, wouldn't that automagically elimintate a bunch of erroneous
code and simplify programming in C?

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#23605

On Jul 23, 8:32 am, "Ansel" <tinker...@trytospammenowloser.com> wrote:
> If C's unsigned integer types were designed so that their maximum value was
> the same as the absolute value of the same width signed integer type's
> minimum value, wouldn't that automagically elimintate a bunch of erroneous
> code and simplify programming in C?

I'm curious to see an example, which you surely will post.

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#23652

>"christian.bau" <christian.bau@cbau.wanadoo.co.uk> wrote in message 
>news:2d5917c0-6c09-4c23-8672-d9aed340d1ea@l5g2000vbo.googlegroups.com...
>On Jul 23, 8:32 am, "Ansel" <tinker...@trytospammenowloser.com> wrote:
>> If C's unsigned integer types were designed so that their maximum value 
>> was
>> the same as the absolute value of the same width signed integer type's
>> minimum value, wouldn't that automagically elimintate a bunch of 
>> erroneous
>> code and simplify programming in C?
>
>I'm curious to see an example, which you surely will post.

Well the obvious one is that you could assign the negative of any unsigned 
int to an int without a care. It just seems conceptually simpler: less 
thinking about trivial details in the solution domain required. Maybe not 
overall though -- I'd have to think about it some more. I'd bet no one even 
ever considered that way back when. Rather, they probably just thought, 
"there are 8-bits, so we *must* utilize them". Conceptual simplicity 
probably never entered anyone's mind. The hardware drove the design. Or so I 
wonder.

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#23663

"Ansel" <tinker454@trytospammenowloser.com> writes:

>>"christian.bau" <christian.bau@cbau.wanadoo.co.uk> wrote in message 
>>news:2d5917c0-6c09-4c23-8672-d9aed340d1ea@l5g2000vbo.googlegroups.com...
>>On Jul 23, 8:32 am, "Ansel" <tinker...@trytospammenowloser.com> wrote:
>>> If C's unsigned integer types were designed so that their maximum value 
>>> was
>>> the same as the absolute value of the same width signed integer type's
>>> minimum value, wouldn't that automagically elimintate a bunch of 
>>> erroneous
>>> code and simplify programming in C?
>>
>>I'm curious to see an example, which you surely will post.
>
> Well the obvious one is that you could assign the negative of any unsigned 
> int to an int without a care. It just seems conceptually simpler: less 
> thinking about trivial details in the solution domain required. Maybe not 
> overall though -- I'd have to think about it some more.

I'm curious to see an example.

<snip>
-- 
Ben.

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#23696

"Ben Bacarisse" <ben.usenet@bsb.me.uk> wrote in message 
news:0.9437614bb6d82b2295aa.20120724112513BST.87vchdtq0m.fsf@bsb.me.uk...
> "Ansel" <tinker454@trytospammenowloser.com> writes:
>
>>>"christian.bau" <christian.bau@cbau.wanadoo.co.uk> wrote in message
>>>news:2d5917c0-6c09-4c23-8672-d9aed340d1ea@l5g2000vbo.googlegroups.com...
>>>On Jul 23, 8:32 am, "Ansel" <tinker...@trytospammenowloser.com> wrote:
>>>> If C's unsigned integer types were designed so that their maximum value
>>>> was
>>>> the same as the absolute value of the same width signed integer type's
>>>> minimum value, wouldn't that automagically elimintate a bunch of
>>>> erroneous
>>>> code and simplify programming in C?
>>>
>>>I'm curious to see an example, which you surely will post.
>>
>> Well the obvious one is that you could assign the negative of any 
>> unsigned
>> int to an int without a care. It just seems conceptually simpler: less
>> thinking about trivial details in the solution domain required. Maybe not
>> overall though -- I'd have to think about it some more.
>
> I'm curious to see an example.
>

I was wondering. If you say "it ain't so", I will not "just believe you", 
because I actually want to *know* "it ain't so". I am seeking an 
analyis/discussion. 

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#23701

"Ansel" <tinker454@trytospammenowloser.com> writes:

> "Ben Bacarisse" <ben.usenet@bsb.me.uk> wrote in message 
> news:0.9437614bb6d82b2295aa.20120724112513BST.87vchdtq0m.fsf@bsb.me.uk...
<snip>
>>>>On Jul 23, 8:32 am, "Ansel" <tinker...@trytospammenowloser.com> wrote:
>>>>> If C's unsigned integer types were designed so that their maximum value
>>>>> was
>>>>> the same as the absolute value of the same width signed integer type's
>>>>> minimum value, wouldn't that automagically elimintate a bunch of
>>>>> erroneous
>>>>> code and simplify programming in C?
<snip>
>> I'm curious to see an example.
>
> I was wondering. If you say "it ain't so", I will not "just believe you", 
> because I actually want to *know* "it ain't so". I am seeking an 
> analyis/discussion. 

I thought that maybe you'd concluded that your suggestion would
"simplify programming in C" because you'd worked through some examples,
examples you could then share.  If not, no worries.  I just like to know
what lies behind such posts because it helps me know how seriously to
take them.

-- 
Ben.

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#23704

"Ben Bacarisse" <ben.usenet@bsb.me.uk> wrote in message 
news:0.455195f780fde9316baf.20120725015336BST.87obn4r78v.fsf@bsb.me.uk...
> "Ansel" <tinker454@trytospammenowloser.com> writes:
>
>> "Ben Bacarisse" <ben.usenet@bsb.me.uk> wrote in message
>> news:0.9437614bb6d82b2295aa.20120724112513BST.87vchdtq0m.fsf@bsb.me.uk...
> <snip>
>>>>>On Jul 23, 8:32 am, "Ansel" <tinker...@trytospammenowloser.com> wrote:
>>>>>> If C's unsigned integer types were designed so that their maximum 
>>>>>> value
>>>>>> was
>>>>>> the same as the absolute value of the same width signed integer 
>>>>>> type's
>>>>>> minimum value, wouldn't that automagically elimintate a bunch of
>>>>>> erroneous
>>>>>> code and simplify programming in C?
> <snip>
>>> I'm curious to see an example.
>>
>> I was wondering. If you say "it ain't so", I will not "just believe you",
>> because I actually want to *know* "it ain't so". I am seeking an
>> analyis/discussion.
>
> I thought that maybe you'd concluded that your suggestion would
> "simplify programming in C" because you'd worked through some examples,
> examples you could then share.  If not, no worries.  I just like to know
> what lies behind such posts because it helps me know how seriously to
> take them.
>

Oh, no -- I was just "throwing it out there" for the gurus, so as to not 
waste anymore time on it than necessary. It was more like, "hey, did anyone 
ever/even consider this?", because I assert that just having the hardware 
there could have block some trains of thought on the possibilities. I really 
don't know, so I "threw it out there". I'm really not the one to the 
potential use cases, and it's probably a team-thing anyway -- a la, this 
newsgroup (!).

So far, we *know* full-range unsigneds are "very-nice-to-haves" (for 
character types and such), but java seems to do alright without them. In the 
cases where someone wants a full-range unsigned, like character types, are 
those kinds of things always non-arithmetic types? If so, maybe then the 
"half-range" arithmetic unsigned integer idea becomes plausible. Umm... I 
seem to be moving toward nixing the unsigned arithmetic integer types 
altogether, like java did, huh! 

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#23698

On Jul 24, 7:19 am, "Ansel" <tinker...@trytospammenowloser.com> wrote:
> >"christian.bau" <christian....@cbau.wanadoo.co.uk> wrote in message

> >I'm curious to see an example, which you surely will post.
>
> Well the obvious one is that you could assign the negative of any unsigned
> int to an int without a care.

Wow. What a big advantage.
Now what about assigning the positive value of any unsigned int to an
int? Because that doesn't work.

But actually, you f***ed it up completely.
Operations with unsigned int are performed modulo (UINT_MAX + 1).

If you have an unsigned int

    unsigned int u = 1;

then the negative (-u) or -1u is _always_ UINT_MAX, which is equal to
the numerical value of -INT_MIN which is usually one greater than
INT_MAX. Surprise, surprise.

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#23705

"christian.bau" <christian.bau@cbau.wanadoo.co.uk> wrote in message 
news:31ad2cd9-c1b9-4b92-b7bd-5ff84b03fa0a@x21g2000vbc.googlegroups.com...
On Jul 24, 7:19 am, "Ansel" <tinker...@trytospammenowloser.com> wrote:
> > >"christian.bau" <christian....@cbau.wanadoo.co.uk> wrote in message

> > >I'm curious to see an example, which you surely will post.
> >
> > Well the obvious one is that you could assign the negative of any 
> > unsigned
> > int to an int without a care.

Talking-back to myself: But you shouldn't be doing that anyway probably.

>
> Wow. What a big advantage.

It seems to be a "hack-thing" (in a bad way) to be doing anyway.

> Now what about assigning the positive value of any unsigned int to an
> int? Because that doesn't work.

Why wouldn't it?

>
> But actually, you f***ed it up completely.
> Operations with unsigned int are performed modulo (UINT_MAX + 1).

That is *one* type of integer, yes. Maybe "my" idea cannot be evaluated or 
had in isolation, but rather must be analyzed in the context of type system 
as a whole. I have a feeling that the whole discussion is about to become 
moot -- in favor of nixing arithmetic unsigneds altogether.

>
> If you have an unsigned int
>
>     unsigned int u = 1;
>
> then the negative (-u) or -1u is _always_ UINT_MAX, which is equal to
> the numerical value of -INT_MIN which is usually one greater than
> INT_MAX. Surprise, surprise. 

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#23709

"Ansel" <tinker454@trytospammenowloser.com> writes:
> "christian.bau" <christian.bau@cbau.wanadoo.co.uk> wrote in message 
> news:31ad2cd9-c1b9-4b92-b7bd-5ff84b03fa0a@x21g2000vbc.googlegroups.com...
> On Jul 24, 7:19 am, "Ansel" <tinker...@trytospammenowloser.com> wrote:
>> > >"christian.bau" <christian....@cbau.wanadoo.co.uk> wrote in message
>> > >I'm curious to see an example, which you surely will post.
>> >
>> > Well the obvious one is that you could assign the negative of any 
>> > unsigned
>> > int to an int without a care.
>
> Talking-back to myself: But you shouldn't be doing that anyway probably.
>>
>> Wow. What a big advantage.
>
> It seems to be a "hack-thing" (in a bad way) to be doing anyway.
>
>> Now what about assigning the positive value of any unsigned int to an
>> int? Because that doesn't work.
>
> Why wouldn't it?

Under your proposal, you'd might have signed int with a range of
-32768 to +32767, and unsigned int with a range of 0 to +32768.
You wouldn't be able to assign an unsigned int value of +32768
to a signed int object without changing the mathematical value.
(Adjust values for 32-bit ints.)

I'm skeptical that your proposal, or anything similar to it, would
be an improvement over what we have now.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
    Will write code for food.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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#23712

"Keith Thompson" <kst-u@mib.org> wrote in message 
news:lnhasw8ik4.fsf@nuthaus.mib.org...
> "Ansel" <tinker454@trytospammenowloser.com> writes:
>> "christian.bau" <christian.bau@cbau.wanadoo.co.uk> wrote in message
>> news:31ad2cd9-c1b9-4b92-b7bd-5ff84b03fa0a@x21g2000vbc.googlegroups.com...
>> On Jul 24, 7:19 am, "Ansel" <tinker...@trytospammenowloser.com> wrote:
>>> > >"christian.bau" <christian....@cbau.wanadoo.co.uk> wrote in message
>>> > >I'm curious to see an example, which you surely will post.
>>> >
>>> > Well the obvious one is that you could assign the negative of any
>>> > unsigned
>>> > int to an int without a care.
>>
>> Talking-back to myself: But you shouldn't be doing that anyway probably.
>>>
>>> Wow. What a big advantage.
>>
>> It seems to be a "hack-thing" (in a bad way) to be doing anyway.
>>
>>> Now what about assigning the positive value of any unsigned int to an
>>> int? Because that doesn't work.
>>
>> Why wouldn't it?
>
> Under your proposal, you'd might have signed int with a range of
> -32768 to +32767, and unsigned int with a range of 0 to +32768.

-32767 to +32767

> You wouldn't be able to assign an unsigned int value of +32768
> to a signed int object without changing the mathematical value.
> (Adjust values for 32-bit ints.)
>
> I'm skeptical that your proposal, or anything similar to it, would
> be an improvement over what we have now.
>

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#23606

On Mon, 23 Jul 2012 01:32:59 -0600, Ansel wrote:

> If C's unsigned integer types were designed so that their maximum value
> was the same as the absolute value of the same width signed integer type's
> minimum value, wouldn't that automagically elimintate a bunch of erroneous
> code

Maybe, although it would probably introduce at least as much erroneous
code as it eliminated.

> and simplify programming in C?

No.

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#23607

On 23.07.2012 11:37, Nobody wrote:
> On Mon, 23 Jul 2012 01:32:59 -0600, Ansel wrote:
>
>> If C's unsigned integer types were designed so that their maximum value
>> was the same as the absolute value of the same width signed integer type's
>> minimum value, wouldn't that automagically elimintate a bunch of erroneous
>> code
>
> Maybe, although it would probably introduce at least as much erroneous
> code as it eliminated.

At least in 2038...
http://en.wikipedia.org/wiki/Year_2038_problem

>
>> and simplify programming in C?
>
> No.
>

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#23608

"Ansel" <tinker454@trytospammenowloser.com> wrote in message
news:juiuqb$rau$1@speranza.aioe.org...
> If C's unsigned integer types were designed so that their maximum value
> was
> the same as the absolute value of the same width signed integer type's
> minimum value, wouldn't that automagically elimintate a bunch of erroneous
> code and simplify programming in C?

Assuming an 8-bit int type, the normal signed/unsigned ranges might be -128
to +127, and 0 to 255.

You're suggesting the unsigned range ought to be 0 to 128?

That sounds very difficult to implement; what happens if  you have 128
unsigned, and add one? Every arithmetic operation would need extra code to
detect the overflow, and convert numbers such as +129 to 0. With a few
special cases such as 128+128.

You would also be wasting most of the top bit (only used when representing
128). Then there are the illegal values 129 to 255, which uninitialised data
is likely to have.

And then, with the char type, you would also be limited to a maximum of
+128, cutting out most of the extra ANSI characters.

In fact, every piece of coding relying on a byte having a range of 0 to 255
(as used in much of the internet for example), would need rewriting to use a 
wider int to cover that range.

And what happens when, for example, reading a file of 8-bit characters which
have been created when the range allowed +130 to 255 (eg. much of the
world's stored data); you would now have a block of illegal values instead.

So I can see a few snags with the idea.

-- 
Bartc
 

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#23651

"BartC" <bc@freeuk.com> wrote in message news:juj9b4$25k$1@dont-email.me...
>
>
> "Ansel" <tinker454@trytospammenowloser.com> wrote in message
> news:juiuqb$rau$1@speranza.aioe.org...
>> If C's unsigned integer types were designed so that their maximum value
>> was
>> the same as the absolute value of the same width signed integer type's
>> minimum value, wouldn't that automagically elimintate a bunch of 
>> erroneous
>> code and simplify programming in C?
>
> Assuming an 8-bit int type,

I was actually thinking about every width *except* 8-bits when I posted.

> the normal signed/unsigned ranges might be -128
> to +127, and 0 to 255.
>
> You're suggesting the unsigned range ought to be 0 to 128?

That would be the scene with *your* 8-bit int type, yes. And I wasn't 
"suggesting", I was wondering.

>
> That sounds very difficult to implement;

It's quite simple actually.

> what happens if  you have 128
> unsigned, and add one?

That depends on the type of integer: saturating or modular or 
except-on-overflow. Note that my OP was basically referring to a "ranged", 
or "range-restricted", integer.

> Every arithmetic operation would need extra code

Indeed it would, but it is minor and in most cases not detriental and it 
wouldn't preclude having another integer type called "fast-and-less-safe 
integer" or something. I.e., should the concept pan out to be worthwhile. 
And again, I wasn't *suggesting* with my OP, rather just throwing a thought 
on the table for discussion.

>detect the overflow, and convert numbers such as +129 to 0. With a few
> special cases such as 128+128.
>
> You would also be wasting most of the top bit (only used when representing
> 128). Then there are the illegal values 129 to 255, which uninitialised 
> data
> is likely to have.
>
> And then, with the char type, you would also be limited to a maximum of
> +128, cutting out most of the extra ANSI characters.
>
> In fact, every piece of coding relying on a byte having a range of 0 to 
> 255
> (as used in much of the internet for example), would need rewriting to use 
> a wider int to cover that range.

Noted above. For 'char' and 'byte' types allow the full unsigned range. 
Probably, for all unsigned ints that are not arithmetic types.

>
> And what happens when, for example, reading a file of 8-bit characters 
> which
> have been created when the range allowed +130 to 255 (eg. much of the
> world's stored data); you would now have a block of illegal values 
> instead.

1. My scenario was if it had been that way from the start, would we be 
better off.
2. Non-arithmetic types could use the full range that 8-bits allow.

>
> So I can see a few snags with the idea.
>

Name one. ;) 

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#23661

"Ansel" <tinker454@trytospammenowloser.com> wrote in message
news:juld2l$gsb$1@speranza.aioe.org...
>
> "BartC" <bc@freeuk.com> wrote in message
> news:juj9b4$25k$1@dont-email.me...
>>
>>
>> "Ansel" <tinker454@trytospammenowloser.com> wrote in message
>> news:juiuqb$rau$1@speranza.aioe.org...
>>> If C's unsigned integer types were designed so that their maximum value
>>> was
>>> the same as the absolute value of the same width signed integer type's
>>> minimum value, wouldn't that automagically elimintate a bunch of
>>> erroneous
>>> code and simplify programming in C?
>>
>> Assuming an 8-bit int type,
>
> I was actually thinking about every width *except* 8-bits when I posted.

I chose 8-bits to simplify the examples. But, what's special about 8-bits
that they ought to be allowed a conventional unsigned range; perhaps it's
easier to think of examples where things would stop working..?

>> the normal signed/unsigned ranges might be -128
>> to +127, and 0 to 255.
>>
>> You're suggesting the unsigned range ought to be 0 to 128?
>
> That would be the scene with *your* 8-bit int type, yes. And I wasn't
> "suggesting", I was wondering.

OK, choosing a 16-bit type, you were wondering whether the unsigned range
ought to be 0 to 32768 instead of 0 to 65535.

I think it would be simpler to restrict it to 0 to 32767, ie just the
positive values of a signed int type. (That means you can't
represent -(-32768), but you can't do that as a signed value anyway.) Then
you just have to mask the top bit in every operation.

But then, that would be little different from not having unsigned at all,
and and only using the top half of each signed int range.

>
>>
>> That sounds very difficult to implement;
>
> It's quite simple actually.
>
>> what happens if  you have 128
>> unsigned, and add one?
>
> That depends on the type of integer: saturating or modular or
> except-on-overflow. Note that my OP was basically referring to a "ranged",
> or "range-restricted", integer.

There is some merit to ranged-integer types, but the range would need to be
enforced (not popular in C) and the type system becomes massively more
complicated (what's the result of adding a 100..200 type to a 150..250
type?).

Also, a range is usually a subset of the allowed int range; yours would be a
superset! Because the top value will be one more than the normal range of a
signed int.

It *might* work as a range of the full unsigned int type, but that requires
the normal, unconstrained unsigned type to be still available.

Otherwise there are just two many problems, if any arbitrary value of 16, 32
or 64 bits you might encounter, can only ever be represented as signed, so
will be negative half the time. You can't even convert -1 to unsigned, and
back again, as C can now; you can't represent -1 as unsigned at all.

-- 
Bartc 

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#23662

בתאריך יום שלישי, 24 ביולי 2012 10:43:52 UTC+1, מאת Bart:
> 
> I chose 8-bits to simplify the examples. But, what's special about 8-bits
> that they ought to be allowed a conventional unsigned range; perhaps it's
> easier to think of examples where things would stop working..?
> 
You commonly use 8 bit unsigneds to pull out bit strings from an input channel.

Also, as ranges get smaller, you're more likely to use the upper half of the range. Plenty of people use the range 0-255 to represent a colour channel intensity value, or to index into a table of glyphs. However there's not going to be much difference visually between 32 thousand or 64 thousand greyscale values if you go to 16 bit colour channels. Similarly it's unlikely that you have a need for between 32,000 and 64,000 glyphs.

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#23665

"Malcolm McLean" <malcolm.mclean5@btinternet.com> wrote in message
news:ca08c533-bbd7-45b4-b9c4-391770c358cd@googlegroups.com...
> בתאריך יום שלישי, 24 ביולי 2012 10:43:52 UTC+1, מאת Bart:
>>
>> But, what's special about 8-bits
>> that they ought to be allowed a conventional unsigned range

> Also, as ranges get smaller, you're more likely to use the upper half of
> the range.

>Similarly it's unlikely that you have a need for between 32,000 and 64,000
>glyphs.

Unicode seems to think it needs that many (more in fact).

But, any time you want to treat two 8-bit bytes as a single 16-bit unit, or
four as 32-bit, it would be crazy not to have a suitable type to represent 
that, without having to treat half the possible values as negative numbers.
How would you right-shift the result for example?

-- 
Bartc 

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#23673

בתאריך יום שלישי, 24 ביולי 2012 12:04:42 UTC+1, מאת Bart:
> Malcolm McLean;malcolm.mclean5@btinternet.com> wrote in message
>
> Unicode seems to think it needs that many (more in fact).
>
Unicode has 110,000 characters at last count. So 16 bit unsigneds aren't really helpful. You might want a subset of Unicode that has more than 256 characters, but the number of sitations where you want a subset with more than 32,000, less than 64,000, and you don't want to just go to 32 bits in case of future extensions is limited.

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#23675

"Malcolm McLean" <malcolm.mclean5@btinternet.com> wrote in message 
news:d5cf3732-97c3-4dc9-8b6c-505559a28bdb@googlegroups.com...
> בתאריך יום שלישי, 24 ביולי 2012 12:04:42 UTC+1, מאת Bart:
>> Malcolm McLean;malcolm.mclean5@btinternet.com&gt; wrote in message
>>
>> Unicode seems to think it needs that many (more in fact).
>>
> Unicode has 110,000 characters at last count. So 16 bit unsigneds aren't 
> really helpful. You might want a subset of Unicode that has more than 256 
> characters, but the number of sitations where you want a subset with more 
> than 32,000, less than 64,000, and you don't want to just go to 32 bits in 
> case of future extensions is limited.

What you're saying is that you could live with a set of numeric types where 
these ranges:

16-bit: 32768 to 65535 (32769 to 65535 in OP's scheme)
32-bit: 2 billion to 4 billion approx
64-bit: 9 to 18 trillion approx

simply don't exist? At least, without representing them with a bit-pattern 
normally used for negative values, or having to use the next wider type.

That seems too restrictive at this level of language, where you don't have 
recourse to anything lower level without going into machine code.

-- 
Bartc 

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