use strict; 
use warnings;

use 5.018;

my %dispatch = (
    lach => \&Booh::laugh,
    foo   => \&main::bar,
    bar   => \&baz,
    yipp  =>\&jjj::YYY,
);

require "jjj.pl";

package Booh;

sub laugh {
    my $lach = shift // 'hahahahahahah';
    say $lach;
}

1; 

package main;

sub bar {
    my $knete = shift // 'is nich'; 
   say "Bar $knete aus der Kasse";
}

sub baz {
    say 'Bar und Baaaatz';
}

##########

my $coderef = Booh->can('laugh'); $coderef->('hihia'); # Boo::laugh(....)

$dispatch{lach}->('Gacker!!!!!!!!!!!!!!!'); # auch Boo::laugh(....)

$coderef = main->can('bar'); $coderef->(); $coderef->('100 EURO');

$coderef = jjj->can('YYY'); $coderef->(); $coderef->('Yippi');

$dispatch{'yipp'}->('hollaaaaaa');

1;