symfony/polyfill-php54 v1.20.0

The symfony/polyfill-php54 is designed to provide backwards compatibility to scripts written in PHP 5.4 or above, allowing them to run on lower versions of PHP. It does this by implementing functions that do not exist in releases prior to PHP 5.4, like trait_exists, class_uses, hex2bin, and session_register_shutdown.

You can use symfony/polyfill-php54 by including it in your PHP project. Firstly, you will need to add it to your project using composer. You can do that by running the following command in the console:

composer require symfony/polyfill-php54

Now you can use the functions trait_exists, class_uses, hex2bin, and session_register_shutdown in your code, and your project will be compatible with PHP versions lower than 5.4. Here are examples of how you can use each function:

// Check if a trait exists
if(!trait_exists('MyTrait')) {
    echo 'Trait does not exist';
}

// Return all traits used by a class
$traits = class_uses('MyClass');

// Decode a hexadecimally encoded binary string
$binary = hex2bin('6578616d706c65206865782064617461');

// Register 'shutdown' to be called when the script ends
session_register_shutdown('shutdown');

The documentation for symfony/polyfill-php54 is located in the main README of the symfony/polyfill GitHub project, which you can access here. The documentation provides further information about the functionality of the package, as well as details about the license under which it is released.