Book Image

Learning PHP 7 High Performance

Book Image

Learning PHP 7 High Performance

Overview of this book

PHP is a great language for building web applications. It is essentially a server-side scripting language that is also used for general-purpose programming. PHP 7 is the latest version, providing major backward-compatibility breaks and focusing on high performance and speed. This fast-paced introduction to PHP 7 will improve your productivity and coding skills. The concepts covered will allow you, as a PHP programmer, to improve the performance standards of your applications. We will introduce you to the new features in PHP 7 and then will run through the concepts of object-oriented programming (OOP) in PHP 7. Next, we will shed some light on how to improve your PHP 7 applications' performance and database performance. Through this book, you will be able to improve the performance of your programs using the various benchmarking tools discussed. At the end, the book discusses some best practices in PHP programming to help you improve the quality of your code.
Table of Contents (17 chapters)
Learning PHP 7 High Performance
Credits
About the Author
Acknowledgement
About the Reviewer
www.PacktPub.com
Preface
Index

Uniform variable syntax


Most of the time, we may face a situation in which the method, variable, or classes names are stored in other variables. Take a look at the following example:

$objects['class']->name;

In the preceding code, first, $objects['class'] will be interpreted, and after this, the property name will be interpreted. As shown in the preceding example, variables are normally evaluated from left to right.

Now, consider the following scenario:

$first = ['name' => 'second'];
$second = 'Howdy';

echo $$first['name'];

In PHP 5.x, this code would be executed, and the output would be Howdy. However, this is not inconsistent with the left-to-right expression evaluation. This is because $$first should be evaluated first and then the index name, but in the preceding case, it is evaluated as ${$first['name']}. It is clear that the variable syntax is not consistent and may create confusion. To avoid this inconsistency, PHP 7 introduced a new syntax called uniform variable syntax. Without...