$numbers * @param (Closure(T): numeric) $numeric_function * * @return T|null */ function max_by(iterable $numbers, Closure $numeric_function): mixed { $max = null; $max_num = null; foreach ($numbers as $value) { $value_num = $numeric_function($value); if (null === $max_num || $value_num >= $max_num) { $max = $value; $max_num = $value_num; } } return $max; }