basic perl app

test8.pl

package myint;
    use strict;
    use warnings;
    sub import {
        $^H{"myint/in_effect"} = 1;
    }
    sub unimport {
        $^H{"myint/in_effect"} = 0;
    }
    sub in_effect {
        my $level = shift // 0;
        my $hinthash = (caller($level))[10];
        return $hinthash->{"myint/in_effect"};
    }

package MyMaths;
use warnings;
use strict;
use overload '+' => sub {
    my ( $l, $r ) = @_;

    # Pass 1 to check up one call level from here
    if ( myint::in_effect(1) ) {
        int($$l) + int($$r);
    }
    else {
        $$l + $$r;
    }
};

sub new {
    my ( $class, $value ) = @_;
    bless \$value, $class;
}


package main;
use Data::Dumper::Concise;
my $o1 = MyMaths->new(1) ;
my $o2 = MyMaths->new(2) ;

print $o1 + $o2;
print "\n";
print Dumper $o1;
print Dumper $o2;