What are some common pitfalls to avoid when using eval() function in PHP scripts for template rendering?

One common pitfall to avoid when using the eval() function in PHP scripts for template rendering is the potential security risks associated with executing user-inputted code. To prevent this, it is recommended to sanitize and validate any user input before using eval(). Additionally, using eval() can make the code harder to read and maintain, so it is advisable to explore alternative methods for template rendering such as using PHP's built-in templating engines like Twig or Blade.

// Example of how to sanitize and validate user input before using eval() for template rendering
$user_input = $_POST['template_code'];

// Sanitize and validate user input
$clean_input = filter_var($user_input, FILTER_SANITIZE_STRING);

// Check if input is safe to use with eval()
if ($clean_input === $user_input) {
    eval($clean_input);
} else {
    echo "Input is not safe to use with eval()";
}