Note: I answer my own question at the bottom of this post, so maybe this shouldn't be on SOPW. If posting this kind of thing is annoying, sorry... I would have deleted my message except there's no function for doing this that I can see :)

Fletch, thanks for the tip (below)!

I have only been programming perl 6 months or so and am just getting my sea legs, so maybe I shouldn't be asking an xs question. But I'm just curious, and I'm not sure what I should be feeding into the search engines to get an answer to this, and perhaps there are others like me... so here goes. I was browsing cpan

http://search.cpan.org/src/JDUNCAN/Regexp-Copy-0.06/lib/Regexp/Copy.pm
[download]

for module "regexp::copy" where we have

package Regexp::Copy;

use strict;
use vars qw($VERSION @ISA @EXPORT @EXPORT_OK);

use Regexp::Storable;

require Carp;
require Exporter;
require DynaLoader;
require AutoLoader;

@ISA = qw(Exporter DynaLoader);

@EXPORT = qw( );
@EXPORT_OK = qw(re_copy);
$VERSION = '0.06';


bootstrap Regexp::Copy $VERSION;

sub re_copy {
  for (@_) {
    if (uc(ref($_)) eq ref($_) && !$_->isa('Regexp')) {
      Carp::croak "parameters to re_copy must be blessed and isa(Regex
+p)";
    }
  }
  re_copy_xs(@_);
}


1;

__END__
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My question concerns the line

re_copy_xs(@_);
[download]

What is this? From my (admittedly pretty nebulous) understanding of xs, I am guessing that this function is somehow autogenerated... maybe autogenerated in c. Is that correct? Or barking up the wrong tree? Where can I learn more about modules that end in

some_function_xs
[download]

(If this is something one sees commonly that is!) Thanks for your wisdom! thomas.

UPDATE: On second thought, I just noticed we have

use Regexp::Storable;
[download]

I'm guessing the answer to my question lies in this module, and not in some cryptic xs thing. Never mind!

UPDATE 2: Anyway, for what it's worth, whatever re_copy_xs is doing, the source is here:

http://search.cpan.org/src/JDUNCAN/Regexp-Copy-0.06/Copy.xs

I will now stop mucking with things I don't understand :)