Are there alternative approaches to constructing and accessing variables in PHP that are more efficient or secure?

When constructing and accessing variables in PHP, it is important to consider efficiency and security. One alternative approach is to use PHP's filter_var function to sanitize user input and prevent vulnerabilities such as SQL injection or cross-site scripting attacks. Additionally, using PHP's ternary operator can provide a more concise and efficient way to assign values to variables based on conditions.

// Example of using filter_var to sanitize user input
$email = filter_var($_POST['email'], FILTER_SANITIZE_EMAIL);

// Example of using ternary operator for assigning values based on conditions
$isAdmin = ($_SESSION['role'] == 'admin') ? true : false;