0 is executed later * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $hook argument is not a string. * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $callback argument is not callable. * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $priority argument is not an integer. */ public function register($hook, $callback, $priority = 0) { if (is_string($hook) === false) { throw InvalidArgument::create(1, '$hook', 'string', gettype($hook)); } if (is_callable($callback) === false) { throw InvalidArgument::create(2, '$callback', 'callable', gettype($callback)); } if (InputValidator::is_numeric_array_key($priority) === false) { throw InvalidArgument::create(3, '$priority', 'integer', gettype($priority)); } if (!isset($this->hooks[$hook])) { $this->hooks[$hook] = [ $priority => [], ]; } elseif (!isset($this->hooks[$hook][$priority]))