What are some alternative methods to calling functions in PHP scripts for better performance and readability?

When calling functions in PHP scripts, using alternative methods like anonymous functions or closures can improve performance and readability. Anonymous functions allow you to define a function inline without giving it a name, which can be useful for short, one-off functions. Closures are similar to anonymous functions but can capture variables from the surrounding scope, making them more versatile.

// Using anonymous functions
$sum = function($a, $b) {
    return $a + $b;
};

echo $sum(2, 3); // Output: 5

// Using closures
$factor = 10;
$multiplier = function($num) use ($factor) {
    return $num * $factor;
};

echo $multiplier(5); // Output: 50