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Re: Determining the 'type' of a variable, if only its name is given

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On 06/16/12 02:37 AM, Jens Gustedt wrote:
> Am 15.06.2012 10:51, schrieb John Reye:
>> is it possible, to determine the 'type' of a variable, if only its
>> name is given.
>
> [snip things about oldish C99]
>
>> Is there any other way, to determine if a variable var is signed or
>> unsigned, if sizeof(var)<  sizeof(int) ???
>
> with C11's _Generic you may do that, provided your implementation
> hasn't extended integer types that are narrower than int,
>
> you can do something horrible like
>
<snip something horrible>
>
>
>   - the case for "char" works since "unsigned char" can't have padding
>     bits
>   - _Bool is unsigned per definition
>   - then for all cases you have to distinguish all qualified types. at
>     least as quickly I didn't come up with an idea that would force an
>     conversion to an rvalue such that it would drop all qualifiers, and
>     wouldn't promote to the rank of "int"

This could go in a header somewhere: it's similar to C++'s use of the 
numeric_limits template.

-- 
Ian Collins

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Determining the 'type' of a variable, if only its name is given John Reye <jononanon@googlemail.com> - 2012-06-15 01:47 -0700
  Re: Determining the 'type' of a variable, if only its name is given John Reye <jononanon@googlemail.com> - 2012-06-15 01:51 -0700
    Re: Determining the 'type' of a variable, if only its name is given James Kuyper <jameskuyper@verizon.net> - 2012-06-15 08:18 -0400
      Re: Determining the 'type' of a variable, if only its name is given "BartC" <bc@freeuk.com> - 2012-06-15 13:43 +0100
      Re: Determining the 'type' of a variable, if only its name is given Noob <root@127.0.0.1> - 2012-06-15 17:02 +0200
        Re: Determining the 'type' of a variable, if only its name is given Robert Miles <milesrf@Usenet-News.net> - 2012-07-23 23:20 -0500
    Re: Determining the 'type' of a variable, if only its name is given pete <pfiland@mindspring.com> - 2012-06-15 08:21 -0400
    Re: Determining the 'type' of a variable, if only its name is given Jens Gustedt <jens.gustedt@loria.fr> - 2012-06-15 16:37 +0200
      Re: Determining the 'type' of a variable, if only its name is given Ian Collins <ian-news@hotmail.com> - 2012-06-16 09:27 +1200
        Re: Determining the 'type' of a variable, if only its name is given Jens Gustedt <jens.gustedt@loria.fr> - 2012-06-16 09:38 +0200
      Re: Determining the 'type' of a variable, if only its name is given Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-22 20:42 -0700
        Re: Determining the 'type' of a variable, if only its name is given Jens Gustedt <jens.gustedt@loria.fr> - 2012-06-23 14:41 +0200
          Re: Determining the 'type' of a variable, if only its name is given Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-24 10:15 -0700
    Re: Determining the 'type' of a variable, if only its name is given Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-22 20:31 -0700

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