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Re: Length of C++ arrays allocated by operator new[]

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In article <4e525f3f$0$2822$7b1e8fa0@news.nbl.fi>,
Juha Nieminen  <nospam@thanks.invalid> wrote:
>Marcel Müller <news.5.maazl@spamgourmet.com> wrote:
>> Use it for some dozen different types, not just int.
>> Use many functions of the STL containers not just the easiest ones.
>> 
>> Templates have to be instantiated for each unique parameter set. Even if 
>> 90% of the generated functions do not depend on all parameters or the 
>> dependency ends once the compiler has done the type checks, the compiler 
>> will generate distinct implementations. No programmer would repeat his 
>> self that much without the templates (well, hopefully).
>
>  And exactly how would it be different from using non-templated code for
>each used type? If you want an array of ints and an array of doubles,
>you'll have to write twice as much code to handle those arrays. The only
>difference with the templated version is that you will have to write the
>code only once (it's the compiler that does the duplication rather than
>yourself).
>
>  Your argument is as silly as saying "if I write two functions instead
>of one, the size of the binary will increase". Of course it increases.
>You are writing more code.

<Irony on>
Ah, but there are two fantastic alternatives to templates:

1- 
Actually type the code for each types that are being used manually
(well maybe using copy-paste too).  That way, you can line count your
source files in a much more reliable way.  

The fact that you have duplication in your code base.  That this is
harder to maintain and that you could even make an error in one of the
type-specific implementation is negligeable compared to the
incredible benefits of avoiding templates.

2-
Implement a generic container using void *.  That way, your code size
will be a few % points smaller.

The fact that you are loosing type safety (introducing a whole lots
of bug oppurtunities) is negligeable compared to the benefit of
avoiding templates and avoid your executable size to have *exploded* by
a couple of % points. 

<Irony off>

OK, more seriously:

for a trivial program that does nothing useful but only use some
templated container, you may very well be able to notice a significant
increase in size between:

#include <vector>
int main()
{
  std::vector<int> v;
}

and 

#include <vector>
int main()
{
  std::vector<int> v;
  std::vector<char> v;
  std::vector<double> v;
  std::vector<bool> v;
}

etc.

But for a real application that does real work and is composed of
thousands of lines of code, I really doubt that the template
instantiation would make such a significant difference in your
executable size.  This all sounds like premature optimisation to me.
especially with the use of the biased "explode" for executable size
without any figures to back it up. 


Yan

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Length of C++ arrays allocated by operator new[] Marcel Müller <news.5.maazl@spamgourmet.org> - 2011-08-20 15:01 +0200
  Re: Length of C++ arrays allocated by operator new[] Richard Damon <richard@damon-family.org> - 2011-08-20 11:39 -0400
    Re: Length of C++ arrays allocated by operator new[] Marcel Müller <news.5.maazl@spamgourmet.org> - 2011-08-21 22:15 +0200
      Re: Length of C++ arrays allocated by operator new[] Richard Damon <richard@damon-family.org> - 2011-08-22 12:56 -0400
        Re: Length of C++ arrays allocated by operator new[] Marcel Müller <news.5.maazl@spamgourmet.com> - 2011-08-22 22:41 +0200
  Re: Length of C++ arrays allocated by operator new[] Paul <pchristor@yahoo.co.uk> - 2011-08-20 09:20 -0700
    Re: Length of C++ arrays allocated by operator new[] Paul <pchristor@yahoo.co.uk> - 2011-08-20 10:38 -0700
      Re: Length of C++ arrays allocated by operator new[] ruben safir <ruben@mrbrklyn.com> - 2011-08-21 22:33 -0400
        Re: Length of C++ arrays allocated by operator new[] Paul <pchristor@yahoo.co.uk> - 2011-08-22 03:05 -0700
          Re: Length of C++ arrays allocated by operator new[] ruben safir <ruben@mrbrklyn.com> - 2011-08-22 20:05 -0400
            Re: Length of C++ arrays allocated by operator new[] Paul <pchristor@yahoo.co.uk> - 2011-08-22 17:20 -0700
            Re: Length of C++ arrays allocated by operator new[] Paul Brettschneider <paul.brettschneider@yahoo.fr> - 2011-08-23 08:18 +0200
            Re: Length of C++ arrays allocated by operator new[] James Kanze <james.kanze@gmail.com> - 2011-08-26 08:29 -0700
              Re: Length of C++ arrays allocated by operator new[] Noah Roberts <roberts.noah@gmail.com> - 2011-08-26 09:06 -0700
    Re: Length of C++ arrays allocated by operator new[] Juha Nieminen <nospam@thanks.invalid> - 2011-08-20 17:55 +0000
      Re: Length of C++ arrays allocated by operator new[] Paul <pchristor@yahoo.co.uk> - 2011-08-20 10:59 -0700
      Re: Length of C++ arrays allocated by operator new[] legalize+jeeves@mail.xmission.com (Richard) - 2011-08-21 03:07 +0000
  Re: Length of C++ arrays allocated by operator new[] "A" <a@a.a> - 2011-08-20 18:26 +0200
    Re: Length of C++ arrays allocated by operator new[] Leigh Johnston <leigh@i42.co.uk> - 2011-08-20 17:36 +0100
      Re: Length of C++ arrays allocated by operator new[] Marcel Müller <news.5.maazl@spamgourmet.org> - 2011-08-21 22:39 +0200
        Re: Length of C++ arrays allocated by operator new[] Ian Collins <ian-news@hotmail.com> - 2011-08-22 09:08 +1200
        Re: Length of C++ arrays allocated by operator new[] Leigh Johnston <leigh@i42.co.uk> - 2011-08-21 22:32 +0100
          Re: Length of C++ arrays allocated by operator new[] Marcel Müller <news.5.maazl@spamgourmet.org> - 2011-08-22 00:01 +0200
            Re: Length of C++ arrays allocated by operator new[] Leigh Johnston <leigh@i42.co.uk> - 2011-08-22 00:04 +0100
              Re: Length of C++ arrays allocated by operator new[] Ian Collins <ian-news@hotmail.com> - 2011-08-22 11:38 +1200
                Re: Length of C++ arrays allocated by operator new[] Leigh Johnston <leigh@i42.co.uk> - 2011-08-22 01:14 +0100
                Re: Length of C++ arrays allocated by operator new[] Ian Collins <ian-news@hotmail.com> - 2011-08-22 12:27 +1200
              Re: Length of C++ arrays allocated by operator new[] Paul <pchristor@yahoo.co.uk> - 2011-08-21 17:34 -0700
                Re: Length of C++ arrays allocated by operator new[] Leigh Johnston <leigh@i42.co.uk> - 2011-08-22 01:39 +0100
                Re: Length of C++ arrays allocated by operator new[] Paul <pchristor@yahoo.co.uk> - 2011-08-21 18:13 -0700
                Re: Length of C++ arrays allocated by operator new[] Leigh Johnston <leigh@i42.co.uk> - 2011-08-22 12:16 +0100
                Re: Length of C++ arrays allocated by operator new[] Paul <pchristor@yahoo.co.uk> - 2011-08-22 09:09 -0700
                Re: Length of C++ arrays allocated by operator new[] Leigh Johnston <leigh@i42.co.uk> - 2011-08-22 17:22 +0100
                Re: Length of C++ arrays allocated by operator new[] Oliver Jackson <chexmofo@hotmail.com> - 2011-08-22 22:50 -0700
              Re: Length of C++ arrays allocated by operator new[] Juha Nieminen <nospam@thanks.invalid> - 2011-08-22 06:10 +0000
                Re: Length of C++ arrays allocated by operator new[] Leigh Johnston <leigh@i42.co.uk> - 2011-08-22 12:20 +0100
                Re: Length of C++ arrays allocated by operator new[] Noah Roberts <roberts.noah@gmail.com> - 2011-08-26 09:03 -0700
                Re: Length of C++ arrays allocated by operator new[] Nobody <nobody@nowhere.com> - 2011-08-27 02:05 +0100
          Re: Length of C++ arrays allocated by operator new[] Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-08-22 02:06 -0700
        Re: Length of C++ arrays allocated by operator new[] Juha Nieminen <nospam@thanks.invalid> - 2011-08-22 06:06 +0000
          Re: Length of C++ arrays allocated by operator new[] Marcel Müller <news.5.maazl@spamgourmet.com> - 2011-08-22 09:19 +0200
            Re: Length of C++ arrays allocated by operator new[] Goran <goran.pusic@gmail.com> - 2011-08-22 04:50 -0700
            Re: Length of C++ arrays allocated by operator new[] Juha Nieminen <nospam@thanks.invalid> - 2011-08-22 13:53 +0000
              Re: Length of C++ arrays allocated by operator new[] yatremblay@bel1lin202.(none) (Yannick Tremblay) - 2011-08-23 09:40 +0000
                Re: Length of C++ arrays allocated by operator new[] Juha Nieminen <nospam@thanks.invalid> - 2011-08-23 10:03 +0000
        Re: Length of C++ arrays allocated by operator new[] yatremblay@bel1lin202.(none) (Yannick Tremblay) - 2011-08-22 11:26 +0000
          Re: Length of C++ arrays allocated by operator new[] Marcel Müller <news.5.maazl@spamgourmet.com> - 2011-08-22 22:32 +0200
      Re: Length of C++ arrays allocated by operator new[] Noah Roberts <roberts.noah@gmail.com> - 2011-08-27 13:30 -0700
        Re: Length of C++ arrays allocated by operator new[] Leigh Johnston <leigh@i42.co.uk> - 2011-08-27 22:23 +0100
  Re: Length of C++ arrays allocated by operator new[] Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-08-22 02:14 -0700
  Re: Length of C++ arrays allocated by operator new[] Gerald Breuer <Gerald.Breuer@Use-Author-Supplied-Address.invalid> - 2011-08-27 22:35 +0200
    Re: Length of C++ arrays allocated by operator new[] Noah Roberts <roberts.noah@gmail.com> - 2011-08-27 15:45 -0700
      Re: Length of C++ arrays allocated by operator new[] Paavo Helde <myfirstname@osa.pri.ee> - 2011-08-28 02:00 -0500
    Re: Length of C++ arrays allocated by operator new[] "Bo Persson" <bop@gmb.dk> - 2011-08-28 16:38 +0200
      Re: Length of C++ arrays allocated by operator new[] Gerald Breuer <Gerald.Breuer@Use-Author-Supplied-Address.invalid> - 2011-08-28 16:49 +0200
        Re: Length of C++ arrays allocated by operator new[] "Bo Persson" <bop@gmb.dk> - 2011-08-28 22:44 +0200
          Re: Length of C++ arrays allocated by operator new[] Gerald Breuer <Gerald.Breuer@Use-Author-Supplied-Address.invalid> - 2011-08-28 23:03 +0200
        Re: Length of C++ arrays allocated by operator new[] James Kanze <james.kanze@gmail.com> - 2011-08-29 04:05 -0700

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