Development

Perl is a family of high-level, general-purpose, interpreted, dynamic programming languages. Perl borrows features from other programming languages including C, shell scripting (sh), AWK, and sed. The language provides powerful text processing facilities without the arbitrary data-length limits of many contemporary Unix tools, facilitating easy manipulation of text files.

This provides tutorial examples and notes about Perl module files and name spaces. Topics include using require() and do() functions to include other script files, using 'package' statement to declare new name spaces; creating new Perl modules in *.pm files.

Based on the Darwinian principle of survival of the fittest, genetic programming uses mutation and replication to produce algorithms for creating ever-improving computer programs. In this column, you'll get to know the genetic algorithm in simple terms. This article provides Perl implementations for some specific tasks, which you can adapt for generic use. To demonstrate the genetic algorithm, the author breeds numbers for fitness to a formula, and letters to form English words.

A mainstay of the Perl culture, JAPH is a short script that produces the output "Just another Perl hacker." Although written for the beginner or intermediate Perl programmer, this article examines a few simple examples of the JAPH genre that will surprise and engage even the most seasoned devotee.

The author writes "CGI::Application builds upon the bedrock of CGI, adding a structure for writing truly reusable Web-applications. CGI::Application takes what works about CGI and simply provides a structure to negate some of the more onerous programming techniques that have cast an unfavorable light upon it. CGI::Application code is so universal and non-proprietary that it works exceedingly well on any operating system and Web server that supports Perl and CGI. The CGI::Application structure makes it possible for authors to distribute, for the first time, fully functional and sophisticated Web-applications via CPAN.

In this Part 21 of "The Perl You Need To Know" series, it covers the Benchmark module � the handy Perl stopwatch that allows you to time, optimize, and slim down on code.

Tired of writing Perl code to parse form data? Take a leaf from the book of the experts and let CGI.pm do all the work for you. This article introduces you to CGI.pm's powerful page construction and form parsing capabilities, with simple examples of how you can use it to simplify your Perl development.

In this Part 10 of "The Perl You Need to Know" series, you will be shown how to work with Perl's list and hash data structures.

This is a comprehensive tutorial on object-oriented programming in Perl. Some of main topics include: Creating a Class, Class Data, Aggregation, Metaclassical Tools, and more.

This Part 5 of the Perl 101 series introduces you to subroutines and teaches you how to structure your code for maximum reusability. Also included: return values, my() and local() constructs, and a marriage proposal.

This is a list of common mistakes that people make when writing Perl scripts and suggestions on how to fix them. Included are general help tips on how to debug - very important particularly for beginners at programming. This list is based on the author's personal experience and complaints found on newsgroups/message boards.

Find out what those server response codes like 401, 404, 500 mean. It can help you troubleshoot minor problems - knowing these are a must if you'll be working on programs that run on a server.

These are a few guidelines to help you solving problems with your CGI Script. Topics include: Short overview of the CGI calling process, Server Errors - The server fails to execute the CGI, Logical Errors (Errors in the program flow), and more.

This tutorial tackles one of the most common newbie questions, how to install your regular joe CGI Script.

This note describes how to get information about a remote user from within a CGI-bin script, and lists the information available.

Hints and tips on debugging Perl CGI scripts and identifying some possible causes of server errors.

One of the methods that the web server uses to pass information to a cgi script is through environmental variables. These are created and assigned appropriate values within the environment that the server spawns for the cgi script. This page highlights some of the most commonly used ones, along with a brief description and notes on possible uses for them.

This article provides a short CGI program that can print every environment variable it knows.

An introduction to sorting, and how to write your own sorting functions easily with perl. Includes some very common examples of sorts.