Windows never ceases to astonish me.

You think that's astonishing? Brace yourself.

The Windows CLI wants redirection operator characters (e.g.,  > < |) in a double-quoted string to be escaped with a  ^ (hat) character if they are preceded by an odd number of backslash-escaped double-quote characters in the string! (Don't even ask what happens if the backslash escapes are themselves backslash-escaped.)

Consider (this just illustrates redirection-character escaping; the scalar/list context problem with the regex is not addressed):

C:\@Work\Perl\junque>dir
 Volume in drive C has no label.
 Volume Serial Number is EC11-ED1D

 Directory of C:\@Work\Perl\junque

07/07/2009  11:42 AM    <DIR>          .
07/07/2009  11:42 AM    <DIR>          ..
07/07/2009  11:41 AM    <DIR>          16
07/07/2009  11:41 AM    <DIR>          17 foo bar
07/07/2009  11:42 AM    <DIR>          18- baz quux
               0 File(s)              0 bytes
               5 Dir(s)  10,227,699,712 bytes free

C:\@Work\Perl\junque>perl -e
"for (<*>) {
   my ($id) = /(\d+)$/ || /^(\d+)/;
   print qq{$_ => \"id=^>$id\" => x \n};
   }
"
16 => "id=>1" => x
17 foo bar => "id=>17" => x
18- baz quux => "id=>18" => x

C:\@Work\Perl\junque>perl -e
"for (<*>) {
   my ($id) = /(\d+)$/ || /^(\d+)/;
   print qq{$_ => \"id=>$id\" => x \n};
   }
"
The system cannot find the path specified.

C:\@Work\Perl\junque>perl -e
"print qq{ (\") \n};
 for (^<*^>) {
   my ($id) = /(\d+)$/ ^|^| /^^(\d+)/;
   print qq{$_ =^> \"id=>$id\" =^> x \n};
   }
"
 (")
16 => "id=>1" => x
17 foo bar => "id=>17" => x
18- baz quux => "id=>18" => x
x => "id=>" => x
[download]

Enjoy!