# test code
my $a = 
'use filtertest;
BEGIN { print "eval test\n"; }
sub {
    print "Hello word\n";
}->();
END { print "eval over\n" }';
eval $a;

##</code><code>##

# module: filtertest
package filtertest;
use Filter::Util::Call;
sub import {
    my($type, @arguments) = @_;
    filter_add(
        sub {
            my($status);
            $status = filter_read();
            s/word/world/g if ($status > 0);
            $status
        } 
    )
}
1;

##</code><code>##

use filtertest; 
print "Hello word\n";