> less testme.pl
#!/usr/bin/perl -w
use strict;
package _Debug;{ 
  our $Filename2Fields  = 1;
  our $HaltOnError      = 2;
  our $DEBUG_OPS        = 3;
  our @EXPORT=qw( Debug $DEBUG_OPS $Filename2Fields $Halt_on_Error);
  use parent 'Exporter';
  sub Debug($$) { my ($what,  $str)=@_;
    if ($what & $DEBUG_OPS) { print STDERR $str; } } }

package Transcode_plug;{
  import _Debug; 
  sub get_fieldAR_from_filename($) {
    my $file=$_[0];
    Debug($Filename2Fields,"get_fieldAR_from_filename($file)\n");
  }
}

Transcode_plug::get_fieldAR_from_filename('dummy');
# vim: ts=2 sw=2
Ishtar:/Audio/scripts> testme.pl
Global symbol "$Filename2Fields" requires explicit package name at ./testme.pl line 16.
Execution of ./testme.pl aborted due to compilation errors.