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Re: is there a way to ask a variable what it is?

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already5chosen@yahoo.com writes:

> On Tuesday, February 18, 2020 at 6:56:18 PM UTC+2, Tim Rentsch wrote:
>
>> Ben Bacarisse <ben.usenet@bsb.me.uk> writes:
>>
>>> [...] C is a statically typed language so all type information,
>>> and everything easily derived from type information, is known at
>>> compile time.
>>
>> I don't think that's right exactly.  For one example, some type
>> information may be known in one translation unit but not known
>> in another.  A declaration like
>>
>>     extern int special_values[];
>>
>> offers partial but not complete type information in this TU, and
>> so is not known at compile time.
>
> What is "a real type", if there is such thing, is unknown, but
> what compiler think about the type when it deals with this
> specific translation unit is know.
>
>> A second example is variable length arrays.  Here the type
>> information is not known until run time, and usually is not fixed
>> but varies with different invocations.
>
> Here we are at philosophical question of "what is considered a
> type?".

There are two meanings of "type" that come into play here.  One
meaning is the type of an identifier (or an expression).  The
second meaning is the type of an object, irrespective of the type
of an expression used to designate the object.  These two
meanings are sometimes called "static type" and "dynamic type",
respectively.  Most of what I was pointing out is that the two
need not be the same, even if in most situations they are.

By the way I am sure that Ben Bacarisse knows all this.  I see in
a later response that his earlier posting was simplified for the
benefit of who he was responding to, and I misunderstood the
intended context of his statement.  Sorry for the confusion.

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is there a way to ask a variable what it is? T <T@invalid.invalid> - 2020-01-28 19:19 -0800
  Re: is there a way to ask a variable what it is? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-29 03:47 +0000
    Re: is there a way to ask a variable what it is? T <T@invalid.invalid> - 2020-01-28 20:20 -0800
      Re: is there a way to ask a variable what it is? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-29 19:18 +0000
        Re: is there a way to ask a variable what it is? Bart <bc@freeuk.com> - 2020-01-29 20:58 +0000
          Re: is there a way to ask a variable what it is? nobody@example.org (Scott) - 2020-01-30 15:59 +0000
            Re: is there a way to ask a variable what it is? scott@slp53.sl.home (Scott Lurndal) - 2020-01-30 16:35 +0000
    Re: is there a way to ask a variable what it is? Siri Cruise <chine.bleu@yahoo.com> - 2020-01-28 21:55 -0800
      Re: is there a way to ask a variable what it is? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-30 00:24 +0000
        solved: Re: is there a way to ask a variable what it is? T <T@invalid.invalid> - 2020-01-29 21:51 -0800
          Re: solved: Re: is there a way to ask a variable what it is? fir <profesor.fir@gmail.com> - 2020-01-30 03:16 -0800
  Re: is there a way to ask a variable what it is? Ian Collins <ian-news@hotmail.com> - 2020-01-29 17:28 +1300
    Re: is there a way to ask a variable what it is? T <T@invalid.invalid> - 2020-01-28 20:55 -0800
      Re: is there a way to ask a variable what it is? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-01-29 06:49 +0000
      Re: is there a way to ask a variable what it is? Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-29 08:08 +0100
      Re: is there a way to ask a variable what it is? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-30 00:14 +0000
        solved: Re: is there a way to ask a variable what it is? T <T@invalid.invalid> - 2020-01-29 21:51 -0800
        Re: is there a way to ask a variable what it is? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-18 08:56 -0800
          Re: is there a way to ask a variable what it is? already5chosen@yahoo.com - 2020-02-19 01:19 -0800
            Re: is there a way to ask a variable what it is? chad <cdalten@gmail.com> - 2020-02-19 02:53 -0800
            Re: is there a way to ask a variable what it is? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-19 12:45 +0000
            Re: is there a way to ask a variable what it is? James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-19 07:55 -0500
            Re: is there a way to ask a variable what it is? Bart <bc@freeuk.com> - 2020-02-19 13:02 +0000
              Re: is there a way to ask a variable what it is? chad <cdalten@gmail.com> - 2020-02-19 07:27 -0800
            Re: is there a way to ask a variable what it is? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-22 09:42 -0800
  Re: is there a way to ask a variable what it is? Robert Wessel <robertwessel2@yahoo.com> - 2020-01-28 22:36 -0600
    Re: is there a way to ask a variable what it is? T <T@invalid.invalid> - 2020-01-28 20:55 -0800
      Re: is there a way to ask a variable what it is? Manfred <noname@add.invalid> - 2020-01-29 13:22 +0100
        Re: is there a way to ask a variable what it is? David Brown <david.brown@hesbynett.no> - 2020-01-29 13:57 +0100
          Re: is there a way to ask a variable what it is? Manfred <noname@add.invalid> - 2020-01-29 17:47 +0100
            Re: is there a way to ask a variable what it is? David Brown <david.brown@hesbynett.no> - 2020-01-30 12:06 +0100
    Re: is there a way to ask a variable what it is? scott@slp53.sl.home (Scott Lurndal) - 2020-01-29 15:10 +0000
      Re: is there a way to ask a variable what it is? Manfred <noname@add.invalid> - 2020-01-29 17:07 +0100
  Re: is there a way to ask a variable what it is? Siri Cruise <chine.bleu@yahoo.com> - 2020-01-28 21:52 -0800
  Re: is there a way to ask a variable what it is? Bart <bc@freeuk.com> - 2020-01-29 11:11 +0000
    Re: is there a way to ask a variable what it is? Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-29 13:30 +0100
      Re: is there a way to ask a variable what it is? Bart <bc@freeuk.com> - 2020-01-29 12:44 +0000
        Re: is there a way to ask a variable what it is? Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-29 14:03 +0100
          Re: is there a way to ask a variable what it is? gazelle@shell.xmission.com (Kenny McCormack) - 2020-01-29 14:03 +0000
          Re: is there a way to ask a variable what it is? Bart <bc@freeuk.com> - 2020-01-29 14:30 +0000
            Re: is there a way to ask a variable what it is? Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-29 15:45 +0100
              Re: is there a way to ask a variable what it is? Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-29 16:28 +0100
                Re: is there a way to ask a variable what it is? T <T@invalid.invalid> - 2020-01-29 08:35 -0800
                Re: is there a way to ask a variable what it is? Bart <bc@freeuk.com> - 2020-01-29 17:34 +0000
                Re: is there a way to ask a variable what it is? Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-29 18:48 +0100
    Re: is there a way to ask a variable what it is? Thiago Adams <thiago.adams@gmail.com> - 2020-01-29 04:43 -0800
      Re: is there a way to ask a variable what it is? David Brown <david.brown@hesbynett.no> - 2020-01-29 14:46 +0100
        Re: is there a way to ask a variable what it is? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-01-29 15:15 +0000
          Re: is there a way to ask a variable what it is? fir <profesor.fir@gmail.com> - 2020-01-29 08:11 -0800
          Re: is there a way to ask a variable what it is? T <T@invalid.invalid> - 2020-01-29 08:38 -0800
  Re: is there a way to ask a variable what it is? Bart <bc@freeuk.com> - 2020-01-29 11:23 +0000
  Re: is there a way to ask a variable what it is? John Bode <jfbode1029@gmail.com> - 2020-01-29 11:55 -0800
  Re: is there a way to ask a variable what it is? jacobnavia <jacob@jacob.remcomp.fr> - 2020-02-19 12:23 +0100
  Re: is there a way to ask a variable what it is? jacobnavia <jacob@jacob.remcomp.fr> - 2020-02-19 12:23 +0100

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