package MyLogger;
require Exporter;

our @ISA = qw[ Exporter ];
our @EXPORT  = qw[ logMessage ];

sub logMessage {
    print STDERR caller() . '::' . shift();
}


##</code><code>##

#! perl -slw
use strict;

package MyScript;
use MyLogger;

logMessage( 'hello' );

package main;
use MyLogger;

logMessage( 'hello' );

##</code><code>##

c:\test>MyScript.pl
MyScript::hello
main::hello