Closures & Arrow Functions in PHP

// Closure (anonymous function)
$greet = function($name) {
    return "Hello, $name";
};

// Closure with use
$message = 'Hello';
$say = function($name) use ($message) {
    return "$message, $name";
};

// Arrow function (PHP 7.4+)
$add = fn($a, $b) => $a + $b;

// Array operations with arrow functions
$numbers = [1, 2, 3];
$doubled = array_map(fn($n) => $n * 2, $numbers);