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Re: Making C more beautiful by not using macros with arguments

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David Kleinecke <dkleinecke@gmail.com> writes:
> In the world of C90 at least.
>  
> I think everybody knows that if I were defining a macro with
> arguments I must leave no spaces between the macro name and
> the following opening parenthesis. 

Right -- though it's important to note that this requirement doesn't
apply to invocations of function-like macros.

> I think everybody who has contemplated this fact will agree that is
> is the ugliest thing in C. 

I cit myself as one more counterexample of your claim.  I haven't taken
the time to decide what the ugliest thing in C is, but this isn't it.
Off the top of my head, I consider trigraphs, multi-character constants,
and the implementation-defined signedness of plain char to be uglier.
YMMV.

[...]

> This "improvement" - if it actually works - is easy to implement -
> just stop writing macros with arguments.

The standard assert() macro cannot be defined as a parameterless macro.
If it were, then

    assert(expr);

would always evalute expr whether NDEBUG is defined or not.

I routinely use function-like macros for logging.  The macro definitions
depend on compile-time flags, and expand to different code depending on
the logging level.  They could not be written correctly as parameterless
macros; the argument would always be evaluated.

Standard library functions are permitted to be additionally defined as
function-like macros.  Defining them as parameterless macros would not
permit bypassing any macro definition by enclosing the function name in
parentheses.  (That's in section 7 of the standard.)

I can write:

    #define MAX(x, y) ((x) > (y) ? (x) : (y))

How would you suggest writing that as a parameterless macro?

-- 
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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Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-05-29 10:36 -0700
  Re: Making C more beautiful by not using macros with arguments Bartc <bc@freeuk.com> - 2015-05-29 19:04 +0100
    Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-05-30 07:30 -0700
      Re: Making C more beautiful by not using macros with arguments Bartc <bc@freeuk.com> - 2015-05-30 15:51 +0100
  Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-05-29 19:26 +0100
    Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-05-30 07:38 -0700
      Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-05-30 21:44 +0100
        Re: Making C more beautiful by not using macros with arguments Bartc <bc@freeuk.com> - 2015-05-30 23:58 +0100
          Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-05-31 00:27 +0100
            Re: Making C more beautiful by not using macros with arguments Bartc <bc@freeuk.com> - 2015-05-31 10:21 +0100
              Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-05-31 11:00 +0100
                Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-05-31 09:45 -0700
                Re: Making C more beautiful by not using macros with arguments Bartc <bc@freeuk.com> - 2015-05-31 18:20 +0100
                Re: Making C more beautiful by not using macros with arguments Keith Thompson <kst-u@mib.org> - 2015-05-31 13:04 -0700
                Re: Making C more beautiful by not using macros with arguments Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2015-05-31 16:11 -0400
                Re: Making C more beautiful by not using macros with arguments Bartc <bc@freeuk.com> - 2015-05-31 21:48 +0100
                Re: Making C more beautiful by not using macros with arguments Keith Thompson <kst-u@mib.org> - 2015-05-31 14:22 -0700
                Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-06-01 11:33 -0700
                Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-05-31 20:37 +0100
                Re: Making C more beautiful by not using macros with arguments Keith Thompson <kst-u@mib.org> - 2015-05-31 14:18 -0700
                Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-05-31 22:44 +0100
                Re: Making C more beautiful by not using macros with arguments Bartc <bc@freeuk.com> - 2015-05-31 23:16 +0100
                Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-06-01 11:58 -0700
                Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-06-02 01:14 +0100
                Re: Making C more beautiful by not using macros with arguments Bartc <bc@freeuk.com> - 2015-06-02 10:31 +0100
                Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-06-02 11:06 +0100
                Re: Making C more beautiful by not using macros with arguments Bartc <bc@freeuk.com> - 2015-06-02 11:39 +0100
                Re: Making C more beautiful by not using macros with arguments "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-06-02 04:02 -0700
                Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-06-02 12:24 +0100
                Re: Making C more beautiful by not using macros with arguments Noob <root@127.0.0.1> - 2015-06-02 15:41 +0200
                Re: Making C more beautiful by not using macros with arguments Richard Heathfield <rjh@cpax.org.uk> - 2015-06-02 15:00 +0100
                Re: Trolls/Cranks/Kooks Noob <root@127.0.0.1> - 2015-06-02 16:41 +0200
                Re: Trolls/Cranks/Kooks Richard Heathfield <rjh@cpax.org.uk> - 2015-06-02 15:56 +0100
                Re: Trolls/Cranks/Kooks Noob <root@127.0.0.1> - 2015-06-02 17:09 +0200
                Re: Trolls/Cranks/Kooks Richard Heathfield <rjh@cpax.org.uk> - 2015-06-02 16:17 +0100
                Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-06-02 15:58 +0100
                Re: Making C more beautiful by not using macros with arguments Dr Nick <nospam-4@temporary-address.org.uk> - 2015-06-02 19:32 +0100
                Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-06-02 11:00 -0700
                Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-06-02 20:13 +0100
      Re: Making C more beautiful by not using macros with arguments Keith Thompson <kst-u@mib.org> - 2015-05-30 15:17 -0700
        Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-05-31 09:12 -0700
          Re: Making C more beautiful by not using macros with arguments Keith Thompson <kst-u@mib.org> - 2015-05-31 13:29 -0700
      Re: Making C more beautiful by not using macros with arguments David Brown <david.brown@hesbynett.no> - 2015-05-31 17:28 +0200
  Re: Making C more beautiful by not using macros with arguments Morris Dovey <mrdovey@iedu.com> - 2015-05-29 13:35 -0500
  Re: Making C more beautiful by not using macros with arguments "Chris M. Thomasson" <nospam@nospam.nospam> - 2015-05-29 13:19 -0700
    Re: Making C more beautiful by not using macros with arguments "Chris M. Thomasson" <nospam@nospam.nospam> - 2015-05-29 13:25 -0700
  Re: Making C more beautiful by not using macros with arguments Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2015-05-29 14:23 -0600
  Re: Making C more beautiful by not using macros with arguments Keith Thompson <kst-u@mib.org> - 2015-05-29 14:16 -0700
    Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-05-30 07:46 -0700
      Re: Making C more beautiful by not using macros with arguments Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2015-05-30 18:28 -0400
        Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-05-31 09:27 -0700
          Re: Making C more beautiful by not using macros with arguments Bartc <bc@freeuk.com> - 2015-05-31 17:59 +0100
            Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-06-01 11:24 -0700
              Re: Making C more beautiful by not using macros with arguments Keith Thompson <kst-u@mib.org> - 2015-06-01 12:15 -0700
                Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-06-01 12:21 -0700
                Re: Making C more beautiful by not using macros with arguments Keith Thompson <kst-u@mib.org> - 2015-06-01 12:53 -0700
          Re: Making C more beautiful by not using macros with arguments Keith Thompson <kst-u@mib.org> - 2015-05-31 13:36 -0700
          Re: Making C more beautiful by not using macros with arguments David Brown <david.brown@hesbynett.no> - 2015-05-31 23:26 +0200
            Re: Making C more beautiful by not using macros with arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-05-31 23:09 +0100
            Re: Making C more beautiful by not using macros with arguments luser droog <luser.droog@gmail.com> - 2015-05-31 15:51 -0700
              Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-06-01 12:08 -0700
        Re: Making C more beautiful by not using macros with arguments James Kuyper <jameskuyper@verizon.net> - 2015-06-01 12:38 -0400
          Re: Making C more beautiful by not using macros with arguments Dr Nick <nospam-4@temporary-address.org.uk> - 2015-06-01 19:20 +0100
          Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-06-01 12:18 -0700
      Re: Making C more beautiful by not using macros with arguments Keith Thompson <kst-u@mib.org> - 2015-05-30 15:43 -0700
        Re: Making C more beautiful by not using macros with arguments David Kleinecke <dkleinecke@gmail.com> - 2015-05-31 09:32 -0700
  Re: Making C more beautiful by not using macros with arguments Les Cargill <lcargill99@comcast.com> - 2015-05-29 22:07 -0500
  Making C more beautiful by not using macros with arguments rick.c.hodgin@gmail.com - 2015-05-30 09:22 -0700
    Re: Making C more beautiful by not using macros with arguments Morris Dovey <mrdovey@iedu.com> - 2015-05-30 14:22 -0500
      Re: Making C more beautiful by not using macros with arguments Bartc <bc@freeuk.com> - 2015-05-30 21:29 +0100
        Re: Making C more beautiful by not using macros with arguments Morris Dovey <mrdovey@iedu.com> - 2015-05-30 22:15 -0500
          Re: Making C more beautiful by not using macros with arguments Morris Dovey <mrdovey@iedu.com> - 2015-06-08 20:16 -0500
  Re: Making C more beautiful by not using macros with arguments David Brown <david.brown@hesbynett.no> - 2015-05-31 17:32 +0200
  Re: Making C more beautiful by not using macros with arguments Richard Heathfield <rjh@cpax.org.uk> - 2015-06-01 22:51 +0100

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