如何使用PHP7的匿名函数和闭包实现更加灵活和可扩展的业务逻辑处理？

$users = [
    'admin' => 'password123',
    'user' => '123456',
];

function login($username, $password, $callback) {
    global $users;
    
    if (isset($users[$username]) && $users[$username] == $password) {
        $callback(true);
    } else {
        $callback(false);
    }
}

$loginCallback = function($success) {
    if ($success) {
        echo '登录成功！';
    } else {
        echo '登录失败！';
    }
};

login('admin', 'password123', $loginCallback);

function processArray($array, $filterFunc, $mapFunc) {
    $result = array_filter($array, function($value) use ($filterFunc) {
        return $filterFunc($value);
    });

    $result = array_map(function($value) use ($mapFunc) {
        return $mapFunc($value);
    }, $result);

    return $result;
}

$data = [1, 2, 3, 4, 5];

$filterFunc = function($value) {
    return $value % 2 == 0;
};

$mapFunc = function($value) {
    return $value * 2;
};

$result = processArray($data, $filterFunc, $mapFunc);

print_r($result);