protected function configure()
    {
        $this->setDefinition(array(
            new InputArgument(self::ARGUMENT_PACKAGE, InputArgument::REQUIRED, 'Package to inspect'),
            new InputArgument(self::ARGUMENT_CONSTRAINT, InputArgument::OPTIONAL, 'Optional version constraint', '*'),
            new InputOption(self::OPTION_RECURSIVE, 'r', InputOption::VALUE_NONE, 'Recursively resolves up to the root package'),
            new InputOption(self::OPTION_TREE, 't', InputOption::VALUE_NONE, 'Prints the results as a nested tree'),
        ));
    }