What are the potential pitfalls of including functions within functions in PHP?

Including functions within functions in PHP can lead to code that is difficult to read, maintain, and debug. It can also cause issues with variable scope and make the code less reusable. To solve this problem, it is better to define functions separately outside of each other and then call them as needed within the main function.

// Define separate functions outside of each other
function innerFunction() {
    // Function logic here
}

function mainFunction() {
    // Call innerFunction within the main function
    innerFunction();
}

// Call the main function
mainFunction();