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Re: Restricted unsigned integer range would have been better?

From	"BartC" <bc@freeuk.com>
Newsgroups	comp.lang.c
Subject	Re: Restricted unsigned integer range would have been better?
Date	2012-07-23 11:33 +0100
Organization	A noiseless patient Spider
Message-ID	<juj9b4$25k$1@dont-email.me> (permalink)
References	<juiuqb$rau$1@speranza.aioe.org>

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"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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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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