...
our @ISA = qw(Person);    # inherits from Person

my $firstName = $object->getFirstName();
print "This is the first name: " . $firstName . "\n";
[download]

Can you explain in English what this code is supposed to do and when it is supposed to be executed?

The code is not in a subroutine so it will run at use time.

Hello Corion,

This is actually the key point of my question. I want to find a way to pass/ inherit the value to my $firstName when the module will be called.

My intention is to use warnings on my script instead of die functions and store the error on a directory.

Sample of pseudo code Employee.pm:

So my question is how to pass the $fileDirectory into %WARNS so I can use it to print the error on correct location. I can pass it as a parameter through main.pl.

Sample of new main.pl:

#!/usr/bin/perl
use Person;
use strict;
use warnings;
use Employee;

my $dirToBePassed = "/path/Dir";

my $object = new Person( "Thanos", "Test", 123456);
my $firstName = $object->getFirstName();
print "This is the first name: $firstName\n";

my $secondObject = new Employee( "refToBeUsed" );
my $solution = $secondObject->somethingCalledFromMain();
print "This is the solution : $solution\n";
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Sample of new Employee.pm

#!/usr/bin/perl
use strict;
use warnings;

package Employee;

sub new
{
    my $class = shift;
    my $self = {
        refFromMain => shift,
    };
    bless $self, $class;
    return $self;
}

sub somethingCalledFromMain
{
    my( $self ) = @_;
=comment
    do something here;
    warn "I was not able to complete the process!\n";
=cut
    return $self->{refFromMain};
}

my %WARNS;
local $SIG{__WARN__} = sub {
    my $message = shift;
    return if $WARNS{$message}++;
    logger('warning', $message);
};

sub logger {
    my ($level, $msg) = @_;
    if (open my $out, '>>', 'log.txt') {
        chomp $msg;
        print $out "$level - $msg\n";
    close $out;
    }
}

1;
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Sample of working output:

This is the first name: Thanos
This is the solution : refToBeUsed
[download]

It is really easy to pass the my $dirToBePassed = "/path/Dir"; to Employee.pm as somethingCalledFromMain($dirToBePassed); with minor code modifications. The problem is how to pass this parameter to %WARNS. So I can print the warnings on the correct directory.

Thank you for your time and effort reading and replying to my question.

Seeking for Perl wisdom...on the process of learning...not there...yet!

Your problem does not show anything related to inheritance - the code shows no relation between Person and Employee.

If you want to do a global capturing of all warnings raised by code in the Employee class, you will need to store the "current" Employee instance in a global variable and then reuse that variable in your %SIG handler for warnings. The easiest approach is to set the "current" employee in the main program:

local $Employee::current= $secondObject;
$secondObject->doSomethingThatRaisesWarnings();
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Note that your statement of

local $SIG{__WARN__} = sub {
...
}
[download]

loses its effect as soon as Employee.pm has been compiled. This may or may not be what you want.

Personally, I would recommend to avoid capturing warnings in such a global way. I think it's better to have your Employee (or Person) class implement a ->logMessage() or ->warn() method that will store the warning with the employee.

Its simple :P use Log::Log4perl / Log::Log4perl::FAQ

Does this make sense ?

Employee::logger_outfile( "/path/Dir" );
...
##Employee.pm
my $outfile ; sub Employee::logger_outfile {
    my $path = shift;
    croak "This is not a method" if ref $path or int@_;
    $outfile = $path;
}
sub Employee::logger {
   open ... $outfile ...
}
[download]

But there are no methods in Employee.pm: all of that codes runs at use time, called from main.pl.

For purposes of demonstration, you probably want to wrap the print in Employee.pm as a printme method, and call it from main, such as $object->printme().

Update:

Don't forget to change $object to the $self idiom.

Hello QM

I read again and again your answer but it is not so clear to me. Is it possible to provide a short sample code of the solution that you propose.

Thanks in advance.

Seeking for Perl wisdom...on the process of learning...not there...yet!

Yes, that error is occurring because you did not declare a variable. But there is a bigger issue: you are trying to execute some code that should be in your client inside your object. Do this instead:

Moose and alternatives can simplify the learning curve:

package Person;
use Moose;
use MooseX::FollowPBP;

has firstName => ( is => 'rw', isa => 'Str', required => 1 );
has lastName  => ( is => 'rw', isa => 'Str', required => 1 );
has ssn       => ( is => 'ro', isa => 'Str' );

sub get_Name { join ' ', $_[0]->get_firstName, $_[0]->get_lastName }


package Employee;
use Moose;
extends 'Person';


package main;
use strict;
use warnings;

my @objects = (
    Person->new( firstName => "Thanos", lastName => "Test", ssn => 123
+456),
    Employee->new( firstName => "Janus", lastName => "Employee", ssn =
+> 998877),
);

print $_->get_Name, $/ for @objects;
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Finally, i can't vouch for that tutorial you linked to. Try perlbootut instead?

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

... http://www.tutorialspoint.com/perl/perl_oo_perl.htm ...

I suggest you start over, while the articles don't include publish date, its very old tutorial, it includes diy hand rolled CGI parameter parsing ... bad practice since 1993

Start with Modern Perl a loose description of how experienced and effective Perl 5 programmers work....You can learn this too.

Or perloop

The error that I am getting when I execute the code: Global symbol "$object" requires explicit package name at Employee.pm

I suggest you forget about OOP until you learn about variables and subroutines

Coping with Scoping and Modern Perl give a good introduction

For more quality up to date tutorials see Perl Tutorial Hub

Hello Anonymous Monk,

I assumed that this is an old tutorial, it looks like it but for a beginner on OO programming it was like a good start.

I have some experience on the areas that you mentioned but I am having difficulty to understand how to overcome my problem.

Thanks again for your time and effort, reading and replying to my question.

Seeking for Perl wisdom...on the process of learning...not there...yet!