What are the best practices for ensuring that the necessary PHP extensions are properly compiled and included for specific functionalities like XSLT processing?

To ensure that the necessary PHP extensions are properly compiled and included for specific functionalities like XSLT processing, you can use the `extension_loaded()` function to check if the required extension is enabled. If it's not enabled, you can enable it in your PHP configuration file or install it using a package manager like PECL.

if (!extension_loaded('xsl')) {
    // Enable XSL extension
    // For example, in php.ini: extension=xsl.so
    // Or install using PECL: pecl install xsl
}