Re: A preprocessor feature we should have had 40 years ago

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From	"Kenneth \"Bessarion\" Boyd" <zaimoni@zaimoni.com>
Newsgroups	comp.std.c++
Subject	Re: A preprocessor feature we should have had 40 years ago
Date	Sat, 25 May 2013 23:43:56 -0700 (PDT)
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On Saturday, May 25, 2013 4:24:09 AM UTC-5, Keith Thompson wrote:
> "Paul D. DeRocco" <pderocco@ix.netcom.com> writes:
>
> > This is going to the C and C++ lists because it is equally applicable to
>
> > both.
>
> >
>
> > I've occasionally needed to use the preprocessor to repeat a piece of
>
> > code some variable number of times. What would be so hard about
>
> > implementing this?
>
> >
>
> >      #repeat <identifier> <const-expression>
>
> >      ...
>
> >      #endrepeat
>
> >
>
> > The expression would be evaluated, and the contents of the block would
>
> > be repeated that number of times, with the preprocessor identifier
>
> > taking values 0 through n-1.

.....

> In my opinion, the need to have simply repeated lines of code like
>
> that is rare enough that it doesn't justify adding a new feature
>
> to the preprocessor and to the language standard.
>
>
>
> I wouldn't have *opposed* adding such a feature to the preprocessor
>
> from the beginning, but I think adding it now would cause more
>
> trouble than it's really worth, as new code that depends on it would
>
> fail to compile on pre-C20XY compilers.  (Which is admittedly an
>
> argument against adding *anything* to the language.)

Especially when this has already been implemented in the Boost
libraries, using a purely standard preprocessor.


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A preprocessor feature we should have had 40 years ago "Paul D. DeRocco" <pderocco@ix.netcom.com> - 2013-05-23 19:18 -0600
  Re: A preprocessor feature we should have had 40 years ago Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-05-24 15:19 -0700
  Re: A preprocessor feature we should have had 40 years ago jacob navia <jacob@spamsink.net> - 2013-05-25 02:23 -0700
  Re: A preprocessor feature we should have had 40 years ago Keith Thompson <kst-u@mib.org> - 2013-05-25 02:24 -0700
    Re: A preprocessor feature we should have had 40 years ago "Kenneth \"Bessarion\" Boyd" <zaimoni@zaimoni.com> - 2013-05-25 23:43 -0700
    Re: A preprocessor feature we should have had 40 years ago "Paul D. DeRocco" <pderocco@ix.netcom.com> - 2013-05-25 23:44 -0700
      Re: A preprocessor feature we should have had 40 years ago Francis Glassborow <francis.glassborow@btinternet.com> - 2013-05-26 08:52 -0600
  Re: A preprocessor feature we should have had 40 years ago Rui Maciel <rui.maciel@googlemail.com> - 2013-05-25 23:43 -0700
  Re: A preprocessor feature we should have had 40 years ago Peter <pcurran88@googlemail.com> - 2013-05-30 19:40 -0600
    Re: A preprocessor feature we should have had 40 years ago "Paul D. DeRocco" <pderocco@ix.netcom.com> - 2013-06-01 02:04 -0600
      Re: A preprocessor feature we should have had 40 years ago ootiib@hot.ee - 2013-06-01 14:53 -0600
      Re: A preprocessor feature we should have had 40 years ago James Kuyper <jameskuyper@verizon.net> - 2013-06-04 10:41 -0600
        Re: A preprocessor feature we should have had 40 years ago espie@lain.home (Marc Espie) - 2013-06-05 23:12 -0700
          Re: A preprocessor feature we should have had 40 years ago James Kuyper <jameskuyper@verizon.net> - 2013-06-06 09:20 -0700
  Re: A preprocessor feature we should have had 40 years ago Jens Schweikhardt <usenet@schweikhardt.net> - 2013-06-09 02:21 -0700

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