Re: for-loop scopes

From	Keith Thompson <kst-u@mib.org>
Newsgroups	comp.lang.c
Subject	Re: for-loop scopes
Date	2017-03-23 08:37 -0700
Organization	None to speak of
Message-ID	<ln1stoats8.fsf@kst-u.example.com> (permalink)
References	<ob0drl$agb$1@dont-email.me>

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BartC <bc@freeuk.com> writes:
> This line in the 'struct padding' thread:
>
>      for(long i = 0; i<N; i++)
>
> prompted me to do more tests:
>
>    {
>      double i;                 // scope 1
>      for (int i=0; i<10; ++i)  // scope 2
>          i;                    // scope 2
>          i;                    // scope 1, deliberate misalignment
>
> Is is correct that the 'int i' inside the for-loop header creates a new 
> scope for the following single statement, even without the existence of 
> a formal {...} block?

Did you try looking it up in the standard before posting?  Why not?

> 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 ';'.

If your code layout is deliberately misleading, it's going to lead to
surprises.  Not all scopes are delimited by curly braces.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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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