Re: macros, was Looking for volunteers for XL

From	Kaz Kylheku <kaz@kylheku.com>
Newsgroups	comp.compilers
Subject	Re: macros, was Looking for volunteers for XL
Date	2011-12-14 19:00 +0000
Organization	A noiseless patient Spider
Message-ID	<11-12-022@comp.compilers> (permalink)
References	(1 earlier) <11-11-061@comp.compilers> <11-11-064@comp.compilers> <11-12-002@comp.compilers> <11-12-017@comp.compilers> <11-12-018@comp.compilers>

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On 2011-12-13, Kaz Kylheku <kaz@kylheku.com> wrote:
> Real macros let you do that: make robust languages that make heavy, dense use
> of those macros, not only some syntactic sugar that is to be sprinkled very
> sparingly.
> [Seems to me that what you really want here is in-line functions.  Macros are
> useful for other stuff, too. -John]

Inline functions don't always fit the bill.

For instance, try this exercise:

Implement the operator or2(A, B) which does this:

1. A is evaluated. If A is nonzero, then the value of A is returned.
2. Otherwise, B is evaluated and its value is returned.

You cannot write this as an inline function or as a non-kludgy macro in C.

Yet this or2 is not some esoteric macro either: it's a simple operator that
is only a tiny semantic modification to C's  || and  ?:   operators.

Both arguments to the macro are expressions! It doesn't reinterpret their
syntax in any way; it just arranges for their evaluation.
[Yeah, you need inline functions with call by name and reference variables.
Yuck. -John]

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Thread

Looking for volunteers for XL Christophe de Dinechin <christophe@taodyne.com> - 2011-11-22 21:03 -0800
  Re: Looking for volunteers for XL Kaz Kylheku <kaz@kylheku.com> - 2011-11-26 05:43 +0000
  Re: Looking for volunteers for XL Christophe de Dinechin <christophe@taodyne.com> - 2011-11-26 12:38 -0800
    Re: Looking for volunteers for XL "BartC" <bc@freeuk.com> - 2011-11-26 23:19 +0000
      Re: Looking for volunteers for XL Christophe de Dinechin <christophe@taodyne.com> - 2011-11-27 12:34 -0800
        Re: Looking for volunteers for XL "BartC" <bc@freeuk.com> - 2011-11-27 22:24 +0000
          Re: Looking for volunteers for XL Christophe de Dinechin <christophe@taodyne.com> - 2011-11-28 14:12 -0800
            Re: Looking for volunteers for XL ardjussi <jussi.santti@ard.fi> - 2011-11-30 13:16 -0800
              Re: Looking for volunteers for XL Kaz Kylheku <kaz@kylheku.com> - 2011-12-01 05:44 +0000
                Re: overloading, was Looking for volunteers for XL glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-12-02 05:36 +0000
          Re: Looking for volunteers for XL tm <thomas.mertes@gmx.at> - 2012-01-03 09:28 -0800
      Re: Looking for volunteers for XL Kaz Kylheku <kaz@kylheku.com> - 2011-11-28 04:45 +0000
        Re: Looking for volunteers for XL Timothy Knox <tdk@thelbane.com> - 2011-11-27 22:50 -0800
          Re: Looking for volunteers for XL Alex McDonald <blog@rivadpm.com> - 2011-12-01 12:11 -0800
        Re: Looking for volunteers for XL "BartC" <bc@freeuk.com> - 2011-11-28 10:23 +0000
          Re: Looking for volunteers for XL glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-11-29 07:37 +0000
            Re: macros, Looking for volunteers for XL Gene Wirchenko <genew@ocis.net> - 2011-12-03 17:36 -0800
              Re: macros, Looking for volunteers for XL glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-12-05 04:24 +0000
          Re: Looking for volunteers for XL Kaz Kylheku <kaz@kylheku.com> - 2011-12-01 05:35 +0000
            Re: designing language extensions, was Looking for volunteers for XL Marco van de Voort <marcov@toad.stack.nl> - 2011-12-03 13:02 +0000
            Re: Looking for volunteers for XL jgk@panix.com (Joe keane) - 2011-12-13 00:08 +0000
              Re: macros, was Looking for volunteers for XL Kaz Kylheku <kaz@kylheku.com> - 2011-12-13 01:39 +0000
                Re: macros, was Looking for volunteers for XL Kaz Kylheku <kaz@kylheku.com> - 2011-12-14 19:00 +0000
                Re: macros, was Looking for volunteers for XL jgk@panix.com (Joe keane) - 2011-12-15 15:40 +0000
                Re: macros, was Looking for volunteers for XL Kaz Kylheku <kaz@kylheku.com> - 2011-12-16 17:48 +0000
        Re: Looking for volunteers for XL glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-11-28 10:26 +0000

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