On Mon, Apr 10, 2006 at 08:38:22PM -0500, Charles K. Clarkson wrote:
> Randal L. Schwartz wrote:
>
> : my $meat;
> : $meat = sub {
> : $meat = sub { real body of loop here } if $. >= 9;
> : };
> :
> : $meat->() while <>;
> :
> : There. Happy?
>
> Smiling? Yes. Happy? No.
>
>
> : No more tests. And now you'll complain about the
> : subroutine call. :)
>
> Are you kidding? I barely understand it.
>
> I'm sure it will work, but I hope I don't have to
> maintain it.
The $meat = sub { . . . } bit creates an anonymous subroutine, and
assigns a reference to it to the $meat variable. This allows you to
effectively pass around code within a variable, to be dereferenced when
you need it. That sort of behavior, particularly within closures and
the like, starts to get into what some call "metaprogramming", where
your programs can sorta "write themselves" on the fly.
That should give you sort of a beginning on understanding what was just
done by Mr. Schwartz. For more, check out the alpaca book (an excellent
read, by the way).
--
Chad Perrin [ CCD CopyWrite | http://ccd.apotheon.org ]
"The measure on a man's real character is what he would do
if he knew he would never be found out." - Thomas McCauley
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