Re: for-loop scopes

From	BartC <bc@freeuk.com>
Newsgroups	comp.lang.c
Subject	Re: for-loop scopes
Date	2017-03-23 13:45 +0000
Organization	A noiseless patient Spider
Message-ID	<ob0jcu$tuo$1@dont-email.me> (permalink)
References	<ob0drl$agb$1@dont-email.me> <ob0hhm$n9j$1@dont-email.me>

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On 23/03/2017 13:14, David Brown wrote:
> On 23/03/17 13:11, BartC wrote:

>>     double i;                 // scope 1
>>     for (int i=0; i<10; ++i)  // scope 2
>>         i;                    // scope 2
>>         i;                    // scope 1, deliberate misalignment

>> I'm just asking because I'm finding it hard to believe that those last
>> two final 'i' terms switch types with merely an intervening ';'.
>>
>
> You don't think it odd that the first "i" is a statement expression
> executed 10 times within the loop while the second "i" is executed
> outside the loop

That's a little bit less odd, but then you know that C loop bodies might 
not end with a specific delimiter such as '}'; it could be just ';'

  - but you /do/ find it odd that the first "i" is in a
> different scope from the second one?  That strikes me as a very strange
> opinion.

Yes; that the first 'i' in 'i;i;' is an int, and the second might be a 
struct, is /more/ odd! You get used to scopes being delimited with {...}.

It is possible to have a scope end half-way through a block, but that is 
signalled by a new declaration at that point.

I suppose it is just necessary to imagine the entire for-loop, complete 
with body, enclosed in {...}.

-- 
bartc

Thread

for-loop scopes BartC <bc@freeuk.com> - 2017-03-23 12:11 +0000
  Re: for-loop scopes David Brown <david.brown@hesbynett.no> - 2017-03-23 14:14 +0100
    Re: for-loop scopes BartC <bc@freeuk.com> - 2017-03-23 13:45 +0000
      Re: for-loop scopes David Brown <david.brown@hesbynett.no> - 2017-03-23 15:48 +0100
      Re: for-loop scopes Robert Wessel <robertwessel2@yahoo.com> - 2017-03-23 23:01 -0500
        Re: for-loop scopes BartC <bc@freeuk.com> - 2017-03-24 10:27 +0000
          Re: for-loop scopes jameskuyper@verizon.net - 2017-03-24 10:43 -0700
          Re: for-loop scopes Robert Wessel <robertwessel2@yahoo.com> - 2017-03-26 21:57 -0500
  Re: for-loop scopes Keith Thompson <kst-u@mib.org> - 2017-03-23 08:37 -0700
  Re: for-loop scopes Ike Naar <ike@iceland.freeshell.org> - 2017-03-23 16:31 +0000
  Re: for-loop scopes "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-03-23 10:23 -0700
    Re: for-loop scopes BartC <bc@freeuk.com> - 2017-03-23 18:07 +0000
      Re: for-loop scopes David Brown <david.brown@hesbynett.no> - 2017-03-23 20:05 +0100
      Re: for-loop scopes jameskuyper@verizon.net - 2017-03-23 12:33 -0700
      Re: for-loop scopes John Bode <jfbode1029@gmail.com> - 2017-03-24 11:35 -0700
  Re: for-loop scopes Noob <root@127.0.0.1> - 2017-03-23 21:06 +0100
  Re: for-loop scopes Andrey Tarasevich <andreytarasevich@hotmail.com> - 2017-03-28 19:15 -0700
    Re: for-loop scopes Andrey Tarasevich <andreytarasevich@hotmail.com> - 2017-03-28 19:19 -0700
    Re: for-loop scopes supercat@casperkitty.com - 2017-03-29 13:14 -0700

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