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Perl & CGI tutorials
 ::   Intro to Perl/CGI and HTML Forms
 ::   Intro to Windows Perl
 ::   Intro to Perl 5
 ::   Intro to Perl
 ::   Intro to Perl Taint mode
 ::   Sherlock Holmes and the Case of the Broken CGI Script
 ::   Writing COM Components in Perl

Java tutorials
 ::   Intro to Java
 ::   Cross Browser Java

Misc technical tutorials
 ::   Intro to The Web Application Development Environment
 ::   Introduction to XML
 ::   Intro to Web Design
 ::   Intro to Web Security
 ::   Databases for Web Developers
 ::   UNIX for Web Developers
 ::   Intro to Adobe Photoshop
 ::   Web Programming 101
 ::   Introduction to Microsoft DNA

Misc non-technical tutorials
 ::   Misc Technopreneurship Docs
 ::   What is a Webmaster?
 ::   What is the open source business model?
 ::   Technical writing
 ::   Small and mid-sized businesses on the Web

Offsite tutorials
 ::   ISAPI Perl Primer
 ::   Serving up web server basics
 ::   Introduction to Java (Parts 1 and 2) in Slovak

 

introduction to web programming
Inheritance in Perl  
Inheritance in Perl 5 is very simple. To do so, you simply declare a class array called @ISA. This array will be used to store the name and parent class(es) of the new species. Whenever the new class is used, it will have this reference to its lineage and be able to check there against method calls and properties.

For example, to define a subclass of Cat, you could use

     package NorthAmericanCat;
     @NorthAmericanCat::ISA = ("Cat");
     sub new {
             [. . . Code goes here . . .]
             }

Notice that in perl 5, package references are handled using the "::" notation. Finally, note that instantiation of an inherited class will work just the same as it did without inheritance.

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