Book Image

PHP 7 Programming Cookbook

By : Doug Bierer
Book Image

PHP 7 Programming Cookbook

By: Doug Bierer

Overview of this book

PHP 7 comes with a myriad of new features and great tools to optimize your code and make your code perform faster than in previous versions. Most importantly, it allows you to maintain high traffic on your websites with low-cost hardware and servers through a multithreading web server. This book demonstrates intermediate to advanced PHP techniques with a focus on PHP 7. Each recipe is designed to solve practical, real-world problems faced by PHP developers like yourself every day. We also cover new ways of writing PHP code made possible only in version 7. In addition, we discuss backward-compatibility breaks and give you plenty of guidance on when and where PHP 5 code needs to be changed to produce the correct results when running under PHP 7. This book also incorporates the latest PHP 7.x features. By the end of the book, you will be equipped with the tools and skills required to deliver efficient applications for your websites and enterprises.
Table of Contents (22 chapters)
PHP 7 Programming Cookbook
Credits
Foreword
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Understanding the abstract syntax tree


As a developer, it might be of interest for you to be free from certain syntax restrictions imposed in PHP 5 and earlier. Aside from the uniformity of the syntax mentioned previously, where you'll see the most improvement in syntax is the ability to call any return value, which is callable by simply appending an extra set of parentheses. Also, you'll be able to directly access any array element when the return value is an array.

How to do it...

  1. Any function or method that returns a callback can be immediately executed by simply appending parentheses () (with or without parameters). An element can be immediately dereferenced from any function or method that returns an array by simply indicating the element using square brackets [];. In the short (but trivial) example shown next, the function test() returns an array. The array contains six anonymous functions. $a has a value of $t. $$a is interpreted as $test:

    function test()
    {
        return [
            1 =&gt...