#!/usr/bin/perl 
use 5.012003;   # Perl version requirement
#===========================================================
# Percentage CLASS (script below)
#===========================================================
package Percentage;
use Any::Moose; 
use namespace::autoclean; 

has 'int' => (
    is => 'ro',
    isa => 'Int',
);

around BUILDARGS => sub {
    my $orig = shift;
    my $class = shift;
    print "build\n";
    return $class->$orig(int => @_);
};

use overload 
    q{""} => \&to_string,
    '0+'  => \&to_num,
    '+'   => \&add;

sub to_string {
    my $self = shift;
    print "to_string()\n";
    return $self->int();
}

sub to_num {
    my $self = shift;
    print "to_num()\n";
    return $self->int();
}

sub add {
    my ($left, $right) = @_;
    print "add()\n";
    my $result = new Percentage( $left->int() + $right->int() );
    return $result;
}
__PACKAGE__->meta->make_immutable;
1;

#===========================================================
# SCRIPT
#===========================================================
package Example::Script;
use 5.012003;   # Perl version requirement
use strict;
use warnings;
                           # printed in output :
my $a = new Percentage(2); # build
print "$a\n";              # Percentage=Hash(0x11cfe8c)
my $a_num = $a->int();     #
my $a_str = "$a";          #
print "$a_str, $a_num\n";  # Percentage=Hash(0x11cfe8c), 2

my $b = new Percentage(3); # build
my $c = $b + $a;           #
print "$b, $c\n";          # Percentage=Hash(0x116912c), 3693356