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)

Positioning regexes with anchors

In many cases, a regex has to be applied to the string in such a way that its beginning coincides with the beginning of the string. For example, if a phone number contains the + character, it can only appear in the first position.

Perl 6 regexes have so-called anchors—special characters, that anchor a regex to either the beginning or the end of the string or a logical line.

Matching at the start and at the end of lines or strings

Let us modify the phone number regex so that it forces the regex to match with the whole string containing a potential phone number:

/ ^ \+? <[\d\s\-]>+ $ /;

Here, ^ is the anchor that matches at the beginning of the string and does not consume any...