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Re: const or constant?

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James Kuyper <jameskuyper@verizon.net> writes:
> On 04/22/2014 05:26 PM, Jens Thoms Toerring wrote:
>> jacob navia <jacob@spamsink.net> wrote:
>>> After reading some of the contrbutions to the "constant strings" thread, 
>>> I think that what is needed is a clarification of the underlying issues.
>> 
>>> There are TWO "uses" of const:
>> 
>>> 1) Declaring that a function will not modify its arguments
>>> 2) Declaring that an object resides in ROM (read only memory)
>> 
>> There's no requirement that a constant of type 2) is in ROM.
>
> Correct. It would be more accurate to say that const-qualification of an
> object allows it to reside in ROM; it doesn't mandate it.

It doesn't always allow it:

    const time_t now = time(NULL);

Of course that can't appear at file scope.

-- 
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"

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Thread

const or constant? jacob navia <jacob@spamsink.net> - 2014-04-22 18:58 +0200
  Re: const or constant? "Bill Cunningham" <nospam@nspam.invalid> - 2014-04-22 14:13 -0400
    Re: const or constant? Barry Schwarz <schwarzb@dqel.com> - 2014-04-22 15:59 -0700
  Re: const or constant? jt@toerring.de (Jens Thoms Toerring) - 2014-04-22 21:26 +0000
    Re: const or constant? James Kuyper <jameskuyper@verizon.net> - 2014-04-22 17:56 -0400
      Re: const or constant? Keith Thompson <kst-u@mib.org> - 2014-04-22 15:32 -0700
        Re: const or constant? James Kuyper <jameskuyper@verizon.net> - 2014-04-23 08:57 -0400
          Re: const or constant? David Brown <david.brown@hesbynett.no> - 2014-04-23 15:27 +0200
            Re: const or constant? Keith Thompson <kst-u@mib.org> - 2014-04-23 08:34 -0700
              Re: const or constant? David Brown <david.brown@hesbynett.no> - 2014-04-24 08:50 +0200
                Re: const or constant? James Kuyper <jameskuyper@verizon.net> - 2014-04-24 07:58 -0400
                Re: const or constant? David Brown <david.brown@hesbynett.no> - 2014-04-24 14:19 +0200
                Re: const or constant? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-24 21:40 +0000
                Re: const or constant? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-25 01:05 -0700
          Re: const or constant? "BartC" <bc@freeuk.com> - 2014-04-23 21:38 +0100
      Re: const or constant? jacob navia <jacob@spamsink.net> - 2014-04-23 00:51 +0200
    Re: const or constant? jacob navia <jacob@spamsink.net> - 2014-04-23 00:47 +0200
  Re: const or constant? Walter Banks <walter@bytecraft.com> - 2014-04-22 18:00 -0400
  Re: const or constant? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-22 23:12 +0100
    Re: const or constant? jacob navia <jacob@spamsink.net> - 2014-04-23 01:00 +0200
      Re: const or constant? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-23 14:48 +0100
        Re: const or constant? Keith Thompson <kst-u@mib.org> - 2014-04-23 08:40 -0700
          Re: const or constant? jacob navia <jacob@spamsink.net> - 2014-04-23 21:49 +0200
            Re: const or constant? Kaz Kylheku <kaz@kylheku.com> - 2014-04-23 20:11 +0000
            [OT] Killfiles (was Re: const or constant?) Keith Thompson <kst-u@mib.org> - 2014-04-23 14:49 -0700
              Re: [OT] Killfiles (was Re: const or constant?) Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-23 22:22 -0700
    Re: const or constant? James Kuyper <jameskuyper@verizon.net> - 2014-04-23 09:09 -0400
  Re: const or constant? Ian Collins <ian-news@hotmail.com> - 2014-04-24 09:35 +1200
    Re: const or constant? Ian Collins <ian-news@hotmail.com> - 2014-04-24 10:06 +1200
      Re: const or constant? Ian Collins <ian-news@hotmail.com> - 2014-04-24 10:52 +1200

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