[dtrace-discuss] dpp(1) - a modest proposal

[Rich Morin]

Peculiarly, in my rather extensive use of cpp with D, I hadn't
even _considered_ the issue of using it to import and process
*.h files.  Obviously, my needs are rather out of the mainstream!

The way I got into all of this was that Leopard's -C option failed
me, so I started running cpp(1) as a separate step.  Given that I
was doing some rather baroque things with macros, being able to see
the expanded form of the code was quite handy.

Then, however, I ran into the facts that (a) the Leopard cpp is not
by any means standard (and I had been relying on some non-standard
behavior :-/) and (b) Solaris can't be relied upon to have cpp or
even cc on its $PATH.  (Interested parties are welcome to peruse my
workaround code in DT_Logger-0.2.tgz, as mentioned previously.)

In retrospect, I'm not sure that cpp was necessarily the best choice
as a preprocessor for the sorts of things I'm doing.  I started out
using it because it was there (and because I needed some way to make
my code a bit shorter and cleaner).  I may also have thought that,
by choosing cpp, I was making my code easier for others to read.

In any case, I intend to give the issue some serious thought, as I
work further on DT_Logger.  Perhaps I need a "program generator" of
some sort; certainly that could make my code substantially shorter!


At 10:42 -0500 12/18/07, James Carlson wrote:
> Would you need that feature in dpp if D itself had string pasting?

If changes to D itself are under consideration, here are a couple of
wish list items:

  *  compile-time string concatenation

     "foo" + "bar" => "foobar"

     Although, to be honest, my main motivation for wanting this is
     the fact that adding a %s to my printf's for the variable name
     caused my programs to run out of kernel space.  If Leopard had
     a way to increase this space, I might not have cared.

  *  more flow-control constructs (if, case, ...)

     I'm not asking for looping, guys, just decent alternation...


At 10:42 -0500 12/18/07, James Carlson wrote:
> What other preprocessor features are specific to D rather than C?

I'm not sure, but I'll give it some thought.

-r
-- 
http://www.cfcl.com/rdm            Rich Morin
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