Book Image

Mastering PHP 7

By : Branko Ajzele
Book Image

Mastering PHP 7

By: Branko Ajzele

Overview of this book

PHP is a server-side scripting language that is widely used for web development. With this book, you will get a deep understanding of the advanced programming concepts in PHP and how to apply it practically The book starts by unveiling the new features of PHP 7 and walks you through several important standards set by PHP Framework Interop Group (PHP-FIG). You’ll see, in detail, the working of all magic methods, and the importance of effective PHP OOP concepts, which will enable you to write effective PHP code. You will find out how to implement design patterns and resolve dependencies to make your code base more elegant and readable. You will also build web services alongside microservices architecture, interact with databases, and work around third-party packages to enrich applications. This book delves into the details of PHP performance optimization. You will learn about serverless architecture and the reactive programming paradigm that found its way in the PHP ecosystem. The book also explores the best ways of testing your code, debugging, tracing, profiling, and deploying your PHP application. By the end of the book, you will be able to create readable, reliable, and robust applications in PHP to meet modern day requirements in the software industry.
Table of Contents (24 chapters)
Title Page
Credits
About the Author
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface
16
Debugging, Tracing, and Profiling

Constant arrays


There are two types of constants in PHP, the constants and the class constants. The constants can be defined pretty much anywhere using the define construct, while the class constants are defined within the individual class or interface using the const keyword.

While we cannot say that one type of constant is more important than the other, PHP 5.6 made the difference between the two by allowing class constants with the array data type. Aside from that difference, both types of constants supported scalar values (integer, float, string, Boolean, or null).

The PHP 7 release addressed this inequality by adding the array data type to constants as well, making the following into valid expressions:

// The class constant - using 'const' keyword
class Rift {
  const APP = [
    'name' => 'Rift',
    'edition' => 'Community',
    'version' => '2.1.2',
    'licence' => 'OSL'
  ];
}

// The class constant - using 'const' keyword
interface IRift {
  const APP = [
    'name' => 'Rift',
    'edition' => 'Community',
    'version' => '2.1.2',
    'licence' => 'OSL'
  ];
}

// The constant - using 'define' construct
define('APP', [
  'name' => 'Rift',
  'edition' => 'Community',
  'version' => '2.1.2',
  'licence' => 'OSL'
]);

echo Rift::APP['version'];
echo IRift::APP['version'];
echo APP['version'];

Though having constants with the array data type might not be an exciting type of feature, it adds a certain flavor to the overall constant use.