private function addCustomVariables(Model $model, $numberOfVarsToAdd, OutputInterface $output) { for ($index = 0; $index < $numberOfVarsToAdd; $index++) { $indexAdded = $model->addCustomVariable(); $this->progress->advance(); $output->writeln(' <info>Added a variable in scope "' . $model->getScopeName() . '" having the index ' . $indexAdded . '</info>'); } }