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Re: Type interchange

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On 12/01/2011 10:55 AM, Ben Bacarisse wrote:
> James Kuyper <jameskuyper@verizon.net> writes:
> 
>> On 11/30/2011 10:09 PM, Ben Bacarisse wrote:
> <snip>
>>> Types are compatible or not as defined by the standard,
>>
>> Yes, and the standard leaves the compatibility of types A and B
>> unspecified for a very large number of possible pairs of A and B,
>> including A='int' and B='long'.
> 
> I don't think it does.  For your interpretation to be correct the
> standard must fail to say if int and long are the same type.  The rule
> is simple:
> 
>   "Two types have compatible type if their types are the
>   same. Additional rules for determining whether two types are
>   compatible..."

I never claimed that 'int' and 'long' could be compatible by reason of
being the same type. When I said that they could be compatible for a
particular implementation, I meant that this possibility exists despite
their being different types.

Some of the other rules referred to by 6.2.7p1 are worded in such a way
that any pair of types that they apply to which aren't identified as
compatible by that rule, must be incompatible. For instance, 6.7.3p9
says "For two qualified types to be compatible, both shall ..."; which
implies quite clearly that any pair of qualified types that don't match
the description following the "shall" are not compatible. However,
neither 'int' nor 'long' is a qualified type, so that doesn't apply.
Neither do any of the other rules referenced by 6.2.7p1.

6.2.7p1 itself contains no such wording. It could have been written as:
For two types to be compatible, they must either be the same type, or
covered by one of the additional rules in ...". It wasn't written that way.

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Thread

Type interchange Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2011-11-30 21:53 +0000
  Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-11-30 17:29 -0500
    Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-11-30 15:22 -0800
      Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-11-30 19:10 -0500
        Re: Type interchange Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-01 03:09 +0000
          Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 07:13 -0500
            Re: Type interchange Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-01 15:55 +0000
              Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 11:28 -0500
                Re: Type interchange Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-01 16:45 +0000
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 12:00 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 14:31 -0800
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 20:18 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 17:35 -0800
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-02 12:03 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-02 13:49 -0800
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-02 22:12 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-03 02:01 -0800
                Re: Type interchange Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-25 12:47 -0800
            Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-01 11:10 -0500
              Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 11:34 -0500
              Re: Type interchange Kaz Kylheku <kaz@kylheku.com> - 2011-12-01 17:48 +0000
              Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 14:17 -0800
                Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-01 17:43 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 15:00 -0800
                Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-01 19:29 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 16:59 -0800
                Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-02 08:35 -0500
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-02 08:46 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-02 13:32 -0800
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-02 13:30 -0800
                Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-02 18:45 -0500
        Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-11-30 19:17 -0800
          Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 06:50 -0500
            Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 07:15 -0800
              Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 10:36 -0500
                Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-01 11:04 -0500
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 11:37 -0500
                Re: Type interchange Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-25 13:02 -0800
            Re: Type interchange Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-25 13:01 -0800
    Re: Type interchange Quentin Pope <qp19433@hotmail.NOSPAM.com> - 2011-12-02 22:15 +0000
      Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-03 11:39 -0500

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