+ naval_fate ship new <name>...
+ naval_fate ship <name> move <x> <y> [--speed=<kn>]
+ naval_fate ship shoot <x> <y>
+ naval_fate mine (set|remove) <x> <y> [--moored|--drifting]
+ -h --help Show this screen.
+ --version Show version.
+ --speed=<kn> Speed in knots [default: 10].
+ --moored Moored (anchored) mine.
+ --drifting Drifting mine.
+ Usage: my_program <host> <port>
+Words starting with ``<``, ending with ``>`` or upper-case words are interpreted
+as positional arguments.
+Words starting with one or two dashes (with exception of ``-``, ``--`` by
+themselves) are interpreted as short (one-letter) or long options,
+All other words that do not follow the above conventions of ``--options`` or
+``<arguments>`` are interpreted as (sub)commands.