the help text for the command
the subcommand path of the command
the subcommand path of the command
the arguments passed to the command
flag name spec ~doc specifies a command that, among other things, takes a flag
named name on its command line. doc indicates the meaning of the flag.
All flags must have a dash at the beginning of the name. If name is not prefixed
by "-", it will be normalized to "-" ^ name.
Unless full_flag_required is used, one doesn't have to pass name exactly on the
command line, but only an unambiguous prefix of name (i.e., a prefix which is not
a prefix of any other flag's name).
NOTE: the doc for a flag which takes an argument should be of the form
arg_name ^ " " ^ description where arg_name describes the argument and
description describes the meaning of the flag.
NOTE: flag names (including aliases) containing underscores will be rejected. Use dashes instead.
NOTE: "-" by itself is an invalid flag name and will be rejected.