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Re: unsigned int

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Les Cargill <lcargill99@comcast.com> writes:
> David Brown wrote:
[...]

> So I'm calling that a swing and a miss. A char is an int that is
> constrained to be less bits.

The name "int" refers to one of several integer types.  `char` is one
integer type, `int` is another.

>                              All chars have exactly the same semantics
> as ints.

No.  All character types have the same semantics as integer types in
general.  Obviously the semantics of signed and unsigned integer types
differ; plain `char` can be either.  And the character types have some
semantics that the other integer types do not (aliasing, requirements
for no padding bits).

>          Default char in 'C' is always unsigned unless you use compiler
> options to make it otherwise, or unless the compiler defaults it for you.

It would be equally accurate to say that `char` is always signed unless
it isn't.

Plain `char` is *either* signed *or* unsigned.  There is no general
sense in which unsigned is the default and signed is not.

[...]

> The problem is that there's a great and powerful simplifying assumption
> in play - 'a' is exactly equivalent to the integer 0xa1. I find this
> quite comforting; it's a simple rule.

Where did you get the value 0xa1?  'a' is 0x61 in ASCII, 0x81 in EBCDIC.

>> I would like a type "byte" which
>> represents raw data in memory - "byte *" would be used instead of "void
>> *" in C, and also in many cases where "char *" is used.
>
> I rather like "void *" because void is the identity un-type - it is a
> type with zero semantic information about it. A void * is a pointer for
> the sake of a pointer, used only as an r-value in order to assign or
> cast to a richer type.

void* is a pointer to arbitrary data.  The suggested "byte" type (or
unsigned char in current C) can *contain* arbitrary data.  Big
difference.

[...]

> Because warnings. With the right compiler options, C++ expects a char * 
> to be a char *, not some typedef equivalent to a char *.
>
> This happens with Mingw 3.4.5 with g++ -I . -Wall -c

Hmm?  In both C and C++, "typedef" creates a new name for an existing
type.  Do you have an example where g++ complains about mixing char*
with a type name that's a typedef for char*?

[...]

> #assert(CHAR_BIT==8) is easy enough.

But non-standard; there is no #assert directive (unless it's an
extension).

[...]

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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Re: unsigned int "Osmium" <r124c4u102@comcast.net> - 2016-07-31 12:40 -0500
  Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-01 11:01 +0200
    Re: unsigned int James Kuyper <jameskuyper@verizon.net> - 2016-08-01 10:15 -0400
    Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-01 09:59 -0500
      Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-01 17:21 +0200
        Re: unsigned int Keith Thompson <kst-u@mib.org> - 2016-08-01 09:55 -0700
          Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-01 22:42 +0200
            Re: unsigned int supercat@casperkitty.com - 2016-08-01 14:18 -0700
        Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-01 13:11 -0500
          Re: unsigned int Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-08-01 19:46 +0100
            Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-01 18:20 -0500
              Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-02 10:18 +0200
                Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-02 09:35 -0500
                Re: unsigned int Keith Thompson <kst-u@mib.org> - 2016-08-02 08:00 -0700
                Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-02 11:12 -0500
                Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-02 17:11 +0200
                Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-02 11:55 -0500
                Re: unsigned int supercat@casperkitty.com - 2016-08-02 10:16 -0700
                Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-03 14:02 +0200
                Re: unsigned int Keith Thompson <kst-u@mib.org> - 2016-08-03 08:58 -0700
                Re: unsigned int James Kuyper <jameskuyper@verizon.net> - 2016-08-02 13:57 -0400
                Re: unsigned int Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-08-02 19:30 +0100
                Re: unsigned int Keith Thompson <kst-u@mib.org> - 2016-08-02 11:38 -0700
                Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-03 14:12 +0200
                Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-03 13:45 +0200
          Re: unsigned int Keith Thompson <kst-u@mib.org> - 2016-08-01 12:02 -0700
            Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-01 23:01 +0200

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