Perl Tutorials - Herong's Tutorial Examples - Version 5.32, by Dr. Herong Yang
Basic Concepts of Classes and Objects
This section describes what is a class and what is an object. Perl uses packages to simulate classes and references to simulate objects.
Class - A user defined complex data type with attributes and operations.
Object - A data instance of the data type defined by a class.
Class variable - An attribute that is shared by all objects of a class. A class variable is also called a static variable.
Object variable - An attribute that is associated with each individual object of a class. An object variable is also called an instance variable.
Class method - An operation that requires a class to be implicitly associated with. A class method is also called static method.
Object method - An operation that requires an object to be implicitly associated with. An object method is also called an instance method.
In order to use classes and objects, other languages have special syntaxes to define classes, declare objects, access attributes, and invoke operations. But Perl tries to extend the package concept to simulate class and extend the reference concept to simulate object.
Table of Contents
Data Types: Values and Variables
Expressions, Operations and Simple Statements
Name Spaces and Perl Module Files
Hard References - Addresses of Memory Objects
►Objects (or References) and Classes (or Packages)
►Basic Concepts of Classes and Objects
Invoking Package Subroutines as Class Methods
bless() - Converting References to Objects
Invoking Package Subroutines as Object Methods
Class Variables and Object Variables
new() Method - Creating Objects by the Class
CalendarClass.pm - A Perl Class Example
Typeglob and Importing Identifiers from Other Packages
String Built-in Functions and Performance
File Handles and Data Input/Output
Open Directories and Read File Names
File System Functions and Operations
Converting Perl Script to Executable Binary
Socket Communication Over the Internet
XML::Simple Module - XML Parser and Generator
SOAP::Lite - SOAP Server-Client Communication Module
Perl Programs as IIS Server CGI Scripts
CGI (Common Gateway Interface)
XML-RPC - Remote Procedure Call with XML and HTTP
RPC::XML - Perl Implementation of XML-RPC
Integrating Perl with Apache Web Server
CGI.pm Module for Building Web Pages