Hi Monks,

I've written a class Lat for latency objects, having min and max values. To sum them I overload '+', pointing to \&add_latency. The overloaded addition fails, due to an extra undefined argument getting into add_latency()'s @_.

Thank you kindly for your attention!

Synopsis

my $lat1 = Lat->new(4,8);
my $lat2 = Lat->new(16,20);
my $okay_sum = $lat1->add_latency($lat2); # this works
my $failed_sum  = $lat1 + $lat2  # overloaded op, gets extra arg

[download]

Below is a test case. I'd like help finding where the third argument comes from. Thanks for your attention.

Any other critique of my code is welcome.

Test code

package Lat;
use Modern::Perl;
our @ISA;
use Data::Dumper::Concise;
use overload '+' => \&add_latency,
             "\"\"" => sub { join ' ',$_[0]->min, $_[0]->max };

sub new {
    my $class = shift;
    my ($min, $max) = @_;
    die "Lat object has Min ($min) greater than Max ($max)" if $min > 
+$max;
    my $self = bless [$min, $max], $class;
    $self;
}
sub add_latency {
    my (@latencies) = @_;
    say "found ",scalar @latencies, " latency objects";
    my $i;
    map{say "Addend ",++$i, "\n", Dumper $_} @latencies;
    my ($min, $max) = (0,0);
    map{ $min += $_->min; $max += $_->max } @latencies;
    Lat->new($min, $max);
}
sub min {$_[0]->[0] }
sub max {$_[0]->[1] }

1;
package main;

use Test::More qw(no_plan);
use strict;
use Data::Dumper::Concise;

#use Lat;

my $lat = Lat->new(4,8);
my $lat2 = Lat->new(16,32);

is(ref $lat, 'Lat', "Latency object instantiation");
is("$lat","4 8","Stringify object");
is($lat->min, 4, "Min latency accessor");
is_deeply( $lat->add_latency($lat2), Lat->new(20,40), "Latency additio
+n");

is_deeply( Lat->new(20,40), ($lat + $lat2), "Latency addition, overloa
+ding '+' operator");

1;
__END__
ok 1 - Latency object instantiation
ok 2 - Stringify object
ok 3 - Min latency accessor
found 2 latency objects
Addend 1
bless( [
  4,
  8
], 'Lat' )

Addend 2
bless( [
  16,
  32
], 'Lat' )

ok 4 - Latency addition
found 3 latency objects
Addend 1
bless( [
  4,
  8
], 'Lat' )

Addend 2
bless( [
  16,
  32
], 'Lat' )

Addend 3
""

Can't call method "min" without a package or object reference at test-
+over2 line 21.
1..4
# Looks like your test exited with 2 just after 4.

[download]

In reply to Overloaded operator ends up with three arguments - SOLVED by gnosti

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