Quick Check Points for Upgrading to PHP 7

The usage statistics posted on various websites depict that PHP is currently more popular than other server-side programming languages. The web developers now have option to upgrade to PHP 7 to avail a number of new features along with enhanced performance and reduced resource consumption. The development team has completely revamped phpng to enhance the speed of the latest version of PHP significantly. According to a number of studies, PHP 7 is about two times faster than PHP 5.6.

At the same time, the developers have also optimized the internal data structure of phpng to reduce memory consumption significantly. The current version of PHP is also designed to perform Facebook HHVM. The development team has increased the PHP code execution speed significantly by using a just in time (JIT) engine to compile the programs written in PHP into machine instructions. Also, PHP 7 enables users to avail several new functions, engine exceptions, and language features. But it does not support a number of features supported by its predecessors. Hence, it becomes essential for web developers to understand the new and deprecated features to upgrade to PHP 7 more efficiently.

Overview of New Features of PHP 7

Option to Declare Types: Many programmers considered PHP to be weakly-typed programming language as it sets types of variables automatically. But the current version of PHP supports type declaration. The feature enables developers to specify the expected data types of variables passed into a function as variables. Hence, the developers can perform various operations accurately by specifying data type of each variable. Also, they can add scalar type hints to the variables and enable strict mode on a file by file basis.

Abstract Syntax Tree: PHP 7.0.0 uses abstract syntax tree as an intermediary structure in the compilation process. So it no longer requires the parser to emit opcodes directly at the time of compilation. The decoupling of parser and complier will make it easier for developers to implement PHP applications. They can further generate quality and maintainable code, while ignoring the technical restrictions imposed by the single-pass compiler used by earlier versions of PHP.

Anonymous Class: Like other popular object-oriented programming languages, PHP 7 too enables programmers to use anonymous class. As the name indicates, an anonymous class has no name. But it can be instantiated through an object with the functionality of object of a named class. The programmers can further create the anonymous class by using the syntax for conventional PHP code. The developers can enhance both coding and execution time by using anonymous classes that is executed only once during execution.

Engine Exceptions: PHP 7.0.0 makes it easier for programmers to handle errors in an application through engine exceptions. It replaces fatal errors and recoverable fatal errors with exceptions. The exception will simplify the process of identifying errors in an application, and taking the most appropriate error. The programmers can simply catch the exception to show appropriate error messages, perform the recovery procedure, or include the errors in log files. However, the developers must keep in mind the working of the engine exceptions while migrating from an earlier version to PHP 7.0.0.

New Functions: PHP 7.0.0 enables programmers to avail several new functions related to math, resources, closure and error-handling. Also, it modifies several functions like exec(), dirname(), mkttime(), substr(), exec() and preg_replace(). The developers can use Closure::call() to bind and call the closure function inside the code. Also, they can use intdiv() can be used to divide two integer variables in a more efficient way. Likewise, they can get the list of resources created by type with the get_resources(), and clear the last error using error_clear_last().

New Operators: In addition to enhanced performance, PHP 7.0.0 also comes with several new language features. It allows developers to use two new operators, i.e., spaceship and null coalesce. The spaceship operator can be used for comparing values more efficiently, while the null coalesce operator can be used for checking it the value is set and not null while performing inline comparisons.

Scalar Type Hints: PHP 7 enables web developers to use scalar type hints to use strings, integers, floats and Boolean as type hints for both methods and functions. They can further define the return type of a function or method. Hence, the programmers can enhance the quality of code by declaring type of function parameters and type of return value. They can further take advantage of scalar type hints to avoid common programming mistakes.

Overview of Deprecated Features of PHP 7

PHP 4 Style Constructors: The latest version of PHP no longer supports PHP 4 style constructors. So the programmers will lack the option to declare functions having the same name as classes. If the constructor is used to define a method inside the class, the browser will display an elaborate error message.

Static Calls to Non-Static Methods: While writing code in PHP 7.0.0, the programmers will lack the option to make static calls to non-static methods. If a programmer tries to make static calls to a non-static method, the browser will indicate the deprecated feature by displaying a detailed error message.

Password_hash() Function: PHP 7.0 no longer supports the passoword_hash() function for generating custom salts. The function made it easier for programmers to create custom but unsecured salts cryptographically when no salt is provided. But the latest version of PHP does not require developers to use custom salts.

Capture_session_meta SSL Context Option: The latest version of PHP does not support capture_session_meta SSL context option. It requires developers to SSL metadata using a new function - stream_get_meta_data().

Deprecated Extensions and SAPIs: The PHP developers also need to know some of the extensions and SAPIs that PHP 7.0.0 does not support. The updated version of PHP no longer supports extensions like mssql, mysql, sybase_ct and ereg. Likewise, it does not support SAPIs like apache and aolserver.

In addition to keeping in mind the new and deprecated features of PHP 7, the web developers also need to check the frameworks and development tools that support the latest version of the server-side programming language. They must remember that many popular PHP frameworks still do not support PHP 7. Hence, they have to pick the right framework to build modern web applications in PHP 7 without putting extra time and effort.