CalledCmd returns the actual command called by the user inferred from the arguments.

InstallConfigFlag adds the -c and --config option to select a configuration file and returns the reference to it.

InstallSocketFlag adds the -s and --sockets options and returns the reference to it.

InstallVerboseFlag adds the -v and -vv options and returns the reference to it.

NoCmd is a no-op command to just make it valid.

NoValidArgs prevents any completion, including files.

RegisterAlias will register a given alias of a command.

SubcommandsRequiredWithSuggestions will ensure we have a subcommand provided by the user and augments it with suggestion for commands, alias and help on root command.

ZeroOrNArgs returns an error if there are not 0 or exactly N arguments for the given command.