Book Image

Perl 6 Deep Dive

By : Andrew Shitov
Book Image

Perl 6 Deep Dive

By: Andrew Shitov

Overview of this book

Perl is a family of high-level, general-purpose, interpreted, dynamic programming languages consisting of Perl 5 and Perl 6. Perl 6 helps developers write concise and declarative code that is easy to maintain. This book is an end-to-end guide that will help non-Perl developers get to grips with the language and use it to solve real-world problems. Beginning with a brief introduction to Perl 6, the first module in the book will teach you how to write and execute basic programs. The second module delves into language constructs, where you will learn about the built-in data types, variables, operators, modules, subroutines, and so on available in Perl 6. Here the book also delves deeply into data manipulation (for example, strings and text files) and you will learn how to create safe and correct Perl 6 modules. You will learn to create software in Perl by following the Object Oriented Paradigm. The final module explains in detail the incredible concurrency support provided by Perl 6. Here you will also learn about regexes, functional programming, and reactive programming in Perl 6. By the end of the book, with the help of a number of examples that you can follow and immediately run, modify, and use in practice, you will be fully conversant with the benefits of Perl 6.
Table of Contents (15 chapters)

Working with attributes

In the previous section, we created the House class, which did not contain anything. Real houses do have some parameters, such as address, area in square meters, number of rooms, height, and so on. All that can be expressed using Perl 6.

Let us start adding the details to the class. We start with the most simple element, the number of rooms. This parameter can be described by an integer value that is attached to the object of the House type. In Perl 6, such data elements are called attributes and are declared with the has keyword, as shown in the following example:

class House {
has $.rooms;
}

What has been done here? The House class got an attribute $.rooms. This is a scalar value that belongs to the class object. Notice the dot after the dollar sigil. It is a twigil that describes the access level to the attribute; we will talk about it later in this...