fix compilation

Author: coke

doc/Type/IO/Path.pod6

@@ -563,6 +563,7 @@ C<'/path/to/file'.IO ~~ :r>
 You can, of course, use an already opened filehandle. Here, using the filehandle
 C<$fh>, is an example, using the method syntax for the file test:
 
+=for code :preamble<my $fh>
     $fh.r
 
 File tests include