addCommand method
Defines a command.
A command is a named argument which may in turn define its own options and
subcommands using the given parser. If parser
is omitted, implicitly
creates a new one. Returns the parser for the command.
Note that adding commands this way will not impact the usage string. To
add commands which are included in the usage string see CommandRunner
.
Implementation
ArgParser addCommand(String name, [ArgParser? parser]) {
// Make sure the name isn't in use.
if (_commands.containsKey(name)) {
throw ArgumentError('Duplicate command "$name".');
}
parser ??= ArgParser();
_commands[name] = parser;
return parser;
}