Thx for the answer. Actually I used a standard header for the script (see below). No idea why it executed despite of the nonsense. 
#!/usr/bin/perl -w
use File::Basename ;
use Fcntl qw (:flock :seek) ;
use warnings ;
use strict ;

use Data::Dumper qw(Dumper);

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In reply to Re^2: How to code a complex AoH? by iatros
in thread How to code a complex AoH? by iatros

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