Re: Implementing static_assert

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From	Keith Thompson <kst-u@mib.org>
Newsgroups	comp.lang.c
Subject	Re: Implementing static_assert
Date	Thu, 07 May 2015 09:11:12 -0700
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David Brown <david.brown@hesbynett.no> writes:
> On 07/05/15 12:53, Philip Lantz wrote:
>> David Brown wrote:
>>> Conversely, I would consider turning an "old-fashioned" assert into a
>>> static assertion if the expression is compile-time constant.
>> 
>> No, you can't do that--even if the expression in an assert is a compile-
>> time constant, the program can't abort unless/until it is executed. 
[...]

> That's why I said I would /consider/ doing this - I realise there are
> cases where you might want to avoid a compile-time error here.

Yes -- and those cases are *all uses of assert()*.

> But certainly it is not something one could change easily without
> breaking existing code.

-- 
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

Implementing static_assert jacobnavia <jacob@jacob.remcomp.fr> - 2015-05-06 21:44 +0200
  Re: Implementing static_assert Keith Thompson <kst-u@mib.org> - 2015-05-06 13:28 -0700
    Re: Implementing static_assert jacobnavia <jacob@jacob.remcomp.fr> - 2015-05-06 22:55 +0200
      Re: Implementing static_assert Keith Thompson <kst-u@mib.org> - 2015-05-06 14:30 -0700
        Re: Implementing static_assert Martin Shobe <martin.shobe@yahoo.com> - 2015-05-06 18:07 -0500
          Re: Implementing static_assert Keith Thompson <kst-u@mib.org> - 2015-05-06 17:34 -0700
          Re: Implementing static_assert David Brown <david.brown@hesbynett.no> - 2015-05-07 09:44 +0200
      Re: Implementing static_assert Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-07 12:37 -0700
  Re: Implementing static_assert David Brown <david.brown@hesbynett.no> - 2015-05-07 10:11 +0200
    Re: Implementing static_assert Ian Collins <ian-news@hotmail.com> - 2015-05-07 22:13 +1200
      Re: Implementing static_assert jacobnavia <jacob@jacob.remcomp.fr> - 2015-05-07 12:24 +0200
        Re: Implementing static_assert Ian Collins <ian-news@hotmail.com> - 2015-05-07 22:33 +1200
          Re: Implementing static_assert David Brown <david.brown@hesbynett.no> - 2015-05-07 14:30 +0200
    Re: Implementing static_assert Philip Lantz <prl@canterey.us> - 2015-05-07 03:53 -0700
      Re: Implementing static_assert David Brown <david.brown@hesbynett.no> - 2015-05-07 14:21 +0200
        Re: Implementing static_assert Keith Thompson <kst-u@mib.org> - 2015-05-07 09:11 -0700
          Re: Implementing static_assert James Kuyper <jameskuyper@verizon.net> - 2015-05-07 12:30 -0400
            Re: Implementing static_assert James Kuyper <jameskuyper@verizon.net> - 2015-05-07 12:55 -0400
    Re: Implementing static_assert Keith Thompson <kst-u@mib.org> - 2015-05-07 09:06 -0700
  Re: Implementing static_assert jacobnavia <jacob@jacob.remcomp.fr> - 2015-05-07 19:43 +0200
    Re: Implementing static_assert Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-07 16:10 -0700

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