Hi Monks.

I am currently learning how to design object oriented programs in Perl and, being very familiar with Java, I began to wonder how the former differs from the latter in this particular aspect. For example: 

public class Example
{
    private String name;
    private int score;

    public Example(String myName, int myScore)
    {
        name = myName;
        score = myScore;
    }

    public String getName()
    {
        return name;
    }
}

[download]


In the above Java class, both 'name' and 'score' are instance variables with a scope (visibility) that extends to both the constructor and the getName method even though the getName method was not constructed with a parameter (the parentheses are empty). Is Perl constructed in a similar manner? In other words, can 'instance variables' be defined outside a constructor? If so, are they visible within every subroutine (method)? 

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

package Example;

# Can variables be defined here? With package level 
# visibility?

sub new {
    my $class = shift;

    my $self = {
        _name => shift,
        _score => shift,
    };

    bless $self, $class;
    return $self;
}

sub getName {
    my ($self) = @_;
    return $self->{_name} || 'No name has been defined!';
}

sub getScore {
    my ($self) = @_;
    return $self->{_score} || 'No score has been entered!';
}

1;

[download]


Is passing variables between methods a common practice in Perl? Can you define a class method in Perl?

Thanks for the help monks.

An inquisitive monkette

In reply to Object oriented Perl and Java: A brief examination of design. by Anonymous Monk

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