#!/usr/bin/perl

use v5.10;

use strict;
use warnings;

use constant {
   BEFORE => 'BEFORE',
};

my $self = {
   HOOK => {
      hello => {
         BEFORE => 'welt',
         123    => 'eine zahl',
      }
   }
};

my $method = 'hello';

say $self->{HOOK}->{$method}->{BEFORE};