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Re: A question on variable scope, coming from a relative beginner

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On 11/12/2015 10:13 PM, Keith Thompson wrote:
> Jon Rossen <jonr17@comcast.net> writes:
>> On 11/12/2015 4:25 PM, Stefan Ram wrote:
>>> Jon Rossen <jonr17@comcast.net> writes:
>>>> extern int x; // This entire statement is not necessary to
>>>
>>>     It's not a statement, it's a declaration (a block-item).
>>>
>>>> omit the 'extern int x' statement completely,
>>>
>>>     »extern int ׫ is not a statement.
>>>
>>
>> Couldn't it be considered both?  In other words can't the term
>> 'statement' be considered a superset that includes smaller subsets such
>> as declarations?
>
> It *could* be, but it isn't.
>
> The C standard defines what a "declaration" is, and what a "statement"
> is, and they're disjoint sets.  There's no fundamental reason for that,
> it's just the way the standard defines the terms.
>
> (In C++, a declaration is considered a kind of statement.  That may have
> been influenced by the fact that C++ permitted mixed declarations and
> statements before C did; C added that feature in C99, but didn't change
> the meanings of "statement" and "declaration".)
>

Keith, much thanks for the further elaboration and the brief historical 
perspective.
-jonR

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A question on variable scope, coming from a relative beginner Jon Rossen <jonr17@comcast.net> - 2015-11-12 13:32 -0800
  Re: A question on variable scope, coming from a relative beginner John Gordon <gordon@panix.com> - 2015-11-12 21:57 +0000
    Re: A question on variable scope, coming from a relative beginner Jon Rossen <jonr17@comcast.net> - 2015-11-12 16:06 -0800
      Re: A question on variable scope, coming from a relative beginner James Kuyper <jameskuyper@verizon.net> - 2015-11-12 19:33 -0500
        Re: A question on variable scope, coming from a relative beginner Jon Rossen <jonr17@comcast.net> - 2015-11-12 20:22 -0800
          Re: A question on variable scope, coming from a relative beginner James Kuyper <jameskuyper@verizon.net> - 2015-11-13 08:08 -0500
  Re: A question on variable scope, coming from a relative beginner Richard Heathfield <rjh@cpax.org.uk> - 2015-11-12 21:57 +0000
    Re: A question on variable scope, coming from a relative beginner Jon Rossen <jonr17@comcast.net> - 2015-11-12 18:47 -0800
      Re: A question on variable scope, coming from a relative beginner James Kuyper <jameskuyper@verizon.net> - 2015-11-12 22:19 -0500
        Re: A question on variable scope, coming from a relative beginner Jon Rossen <jonr17@comcast.net> - 2015-11-12 22:05 -0800
          Re: A question on variable scope, coming from a relative beginner Richard Heathfield <rjh@cpax.org.uk> - 2015-11-13 07:10 +0000
          Re: A question on variable scope, coming from a relative beginner James Kuyper <jameskuyper@verizon.net> - 2015-11-13 08:33 -0500
            Re: A question on variable scope, coming from a relative beginner Tim Rentsch <txr@alumni.caltech.edu> - 2015-11-13 12:24 -0800
            Re: A question on variable scope, coming from a relative beginner Keith Thompson <kst-u@mib.org> - 2015-11-14 11:58 -0800
              Re: A question on variable scope, coming from a relative beginner James Kuyper <jameskuyper@verizon.net> - 2015-11-14 15:27 -0500
  Re: A question on variable scope, coming from a relative beginner Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-11-12 14:00 -0800
    Re: A question on variable scope, coming from a relative beginner Richard Heathfield <rjh@cpax.org.uk> - 2015-11-12 23:55 +0000
  Re: A question on variable scope, coming from a relative beginner Keith Thompson <kst-u@mib.org> - 2015-11-12 17:11 -0800
    Re: A question on variable scope, coming from a relative beginner Jon Rossen <jonr17@comcast.net> - 2015-11-12 20:39 -0800
  Re: A question on variable scope, coming from a relative beginner Jon Rossen <jonr17@comcast.net> - 2015-11-12 20:38 -0800
    Re: A question on variable scope, coming from a relative beginner Keith Thompson <kst-u@mib.org> - 2015-11-12 22:13 -0800
      Re: A question on variable scope, coming from a relative beginner Jon Rossen <jonr17@comcast.net> - 2015-11-15 21:17 -0800

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