use strict;
use warnings;

package Foo;

sub new {
    my $class = shift;
    my $self = { testarray => [] };
    bless $self, $class;
    return $self;
}

sub testfunc {
    my $self = shift;
    my $var  = shift;

    push( @{$self->{testarray}}, $var );
    return 1;
}

sub list {
    my $self = shift;
    return @{$self->{testarray}};
}

package main;

my $foo = new Foo;

$foo->testfunc("a");
$foo->testfunc("b");
print $foo->list, "\n";