Advanced Perl Programming

What Must I Know?

To use Perl effectively in an application, you must be conversant with three aspects:

• The language syntax and idioms afforded by the language.

• The Perl interpreter, for writing C extensions for your Perl scripts or embedding the Perl interpreter in your C/C++ applications.

• Technology issues such as networking, user interfaces, the Web, and persistence.

Figure P.1 shows a map of the topics dealt with in this book. Each major aspect listed above is further classified. The rest of this section presents a small blurb about each topic and the corresponding chapter where the subject is detailed. The discussion is arranged by topic rather than by the sequence in which the chapters appear.

Figure 1. Classification of topics covered in this book

Language Syntax

Pointers or references bring an enormous sophistication to the type of data structures you can create with a language. Perl’s support for references and its ability to let you code without having to specify every single step makes it an especially powerful language. For example, you can create something as elaborate as an array of hashes of arrays^[4] all in a single line. Chapter 1, introduces you to references and what Perl does internally for memory management. Chapter 2, exercises the syntax introduced in the earlier chapter with a few practical examples.

Perl supports references to subroutines and a powerful construct ...