In the context of using PHP on Windows, what are some common issues or challenges that may arise when defining functions, and how can they be addressed?

Issue: One common challenge when defining functions in PHP on Windows is ensuring that the file paths are correctly formatted to work on the Windows operating system. To address this, you can use the `DIRECTORY_SEPARATOR` constant to dynamically generate file paths that are compatible with Windows.

// Define a function with a file path using DIRECTORY_SEPARATOR
function myFunction() {
    $filePath = 'C:' . DIRECTORY_SEPARATOR . 'xampp' . DIRECTORY_SEPARATOR . 'htdocs' . DIRECTORY_SEPARATOR . 'myfile.php';
    // Rest of the function code
}