Gets the first value for the argument with the given name.
Gets all values for the argument with the given name.
Checks whether the given flag name is present.
Checks whether the given flag is present.
Checks whether an argument with the given name is present.
Checks whether the given argument is present.
Checks whether an option with the given name is present.
Checks whether the given option is present.
Gets the first value for the option with the given name.
Gets all values for the option with the given name.
Gets all values for the given option.
Represents parsed command-line arguments for a command.