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Re: Array sizes and const

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"Ian Collins" <ian-news@hotmail.com> wrote in message
news:a327a6F5maU3@mid.individual.net...
> On 06/ 4/12 10:08 AM, Malcolm McLean wrote:

>> could reasonably sort x as a side-effect. Make it const, and you've
>> documented that this isn't the case. I'd say this is sufficiently
>> rare to make const non-useful as a documenting feature.
>
> But what isn't rare is something like
>
> const double dd[] = { 1.0, 2.0, 3.1 };
>
> mean(dd);
>
> Which will trigger an appropriate diagnostic.
>
> If a function doesn't modify a parameter, declare it const.  What's so
> hard about that?

Because nineteen times out of twenty, it won't modify it, so it means loads
of const attributes cluttering up code.

Of course some parameter types can be harmlessly modified (ints for 
example), and const isn't necessary, but then you have to start thinking 
about about every parameter and whether it will be modified in the caller or 
in the callee.

Maybe it would have been better for the modifiable parameters (where it
changes caller's data) to have an attribute instead, and everything else
assumed to be const.

-- 
Bartc 

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Array sizes and const Les Cargill <lcargill99@comcast.com> - 2012-06-02 15:43 -0500
  Re: Array sizes and const Ian Collins <ian-news@hotmail.com> - 2012-06-03 08:56 +1200
  Re: Array sizes and const Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-06-02 16:59 -0400
    Re: Array sizes and const Les Cargill <lcargill99@comcast.com> - 2012-06-02 16:35 -0500
      Re: Array sizes and const jgk@panix.com (Joe keane) - 2012-06-08 20:05 +0000
      Re: Array sizes and const jgk@panix.com (Joe keane) - 2012-06-09 21:36 +0000
    Re: Array sizes and const Les Cargill <lcargill99@comcast.com> - 2012-06-02 16:43 -0500
  Re: Array sizes and const Keith Thompson <kst-u@mib.org> - 2012-06-02 14:59 -0700
    Re: Array sizes and const Les Cargill <lcargill99@comcast.com> - 2012-06-02 17:12 -0500
      Re: Array sizes and const Keith Thompson <kst-u@mib.org> - 2012-06-02 18:27 -0700
        Re: Array sizes and const Les Cargill <lcargill99@comcast.com> - 2012-06-02 22:27 -0500
      Re: Array sizes and const "BartC" <bc@freeuk.com> - 2012-06-03 11:24 +0100
        Re: Array sizes and const Keith Thompson <kst-u@mib.org> - 2012-06-03 13:51 -0700
          Re: Array sizes and const "BartC" <bc@freeuk.com> - 2012-06-04 12:20 +0100
            Re: Array sizes and const Jens Gustedt <jens.gustedt@loria.fr> - 2012-06-04 13:54 +0200
            Re: Array sizes and const Keith Thompson <kst-u@mib.org> - 2012-06-04 14:32 -0700
  Re: Array sizes and const Nobody <nobody@nowhere.com> - 2012-06-02 23:50 +0100
    Re: Array sizes and const Ian Collins <ian-news@hotmail.com> - 2012-06-03 10:53 +1200
      Re: Array sizes and const Nobody <nobody@nowhere.com> - 2012-06-03 14:35 +0100
    Re: Array sizes and const James Kuyper <jameskuyper@verizon.net> - 2012-06-02 21:11 -0400
      Re: Array sizes and const Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-06-03 07:39 -0700
        Re: Array sizes and const James Kuyper <jameskuyper@verizon.net> - 2012-06-03 16:03 -0400
        Re: Array sizes and const Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-06-03 21:49 +0100
          Re: Array sizes and const Keith Thompson <kst-u@mib.org> - 2012-06-03 14:49 -0700
          Re: Array sizes and const Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-06-03 15:02 -0700
            Re: Array sizes and const Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-06-04 01:21 +0100
        Re: Array sizes and const Ian Collins <ian-news@hotmail.com> - 2012-06-04 09:08 +1200
          Re: Array sizes and const Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-06-03 15:08 -0700
            Re: Array sizes and const Ian Collins <ian-news@hotmail.com> - 2012-06-04 10:37 +1200
              Re: Array sizes and const "BartC" <bc@freeuk.com> - 2012-06-03 23:47 +0100
                Re: Array sizes and const Ian Collins <ian-news@hotmail.com> - 2012-06-04 10:55 +1200
                Re: Array sizes and const Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-06-03 16:04 -0700
                Re: Array sizes and const Ian Collins <ian-news@hotmail.com> - 2012-06-04 11:14 +1200
                Re: Array sizes and const "BartC" <bc@freeuk.com> - 2012-06-04 00:23 +0100
                Re: Array sizes and const Ian Collins <ian-news@hotmail.com> - 2012-06-04 11:30 +1200
                Re: Array sizes and const "BartC" <bc@freeuk.com> - 2012-06-04 00:52 +0100
                Re: Array sizes and const Ian Collins <ian-news@hotmail.com> - 2012-06-04 12:04 +1200
                Re: Array sizes and const Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-06-04 01:39 +0100
                Re: Array sizes and const Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-06-04 02:35 -0700
                Re: Array sizes and const Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-06-04 01:33 +0100
                Re: Array sizes and const Ian Collins <ian-news@hotmail.com> - 2012-06-04 12:35 +1200
                Re: Array sizes and const pacman@kosh.dhis.org (Alan Curry) - 2012-06-04 21:28 +0000
        Re: Array sizes and const James Kuyper <jameskuyper@verizon.net> - 2012-06-04 12:08 -0400
        Re: Array sizes and const jgk@panix.com (Joe keane) - 2012-06-04 22:49 +0000
    Re: Array sizes and const David Brown <david.brown@hesbynett.no> - 2012-06-03 15:46 -0500
  Re: Array sizes and const Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-08 02:08 -0700
    Re: Array sizes and const Les Cargill <lcargill99@comcast.com> - 2012-06-08 06:45 -0500
      Re: Array sizes and const Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-08 10:49 -0700
        Re: Array sizes and const Les Cargill <lcargill99@comcast.com> - 2012-06-08 18:05 -0500
    Re: Array sizes and const Keith Thompson <kst-u@mib.org> - 2012-06-08 13:31 -0700
      Re: Array sizes and const Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-08 20:30 -0700

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