#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;
use Devel::Symdump;
use Sub::Installer;

my $PackageName = 'mysub';
my $sub = \&greater;

$PackageName->reinstall_sub({$sub => \&greater});

my $s = Devel::Symdump->new();
print Dumper($s->functions());

sub greater {
  my ($arg1, $arg2) = @_;
  print $arg1 > $arg2 ? $arg1 : $arg2;
}