code: Rule Minor() {
  		return Sequence(IgnoreCase("m"),
  			Optional(Sequence(IgnoreCase("in"),
  				Optional(Sequence(IgnoreCase("o"),
  					Optional(IgnoreCase("r"))
  				))
  			))
  		).label(Minor).suppressSubnodes();
  	}
docs: m, min, mino, minor - all modes are case insensitive
  
  minor ::= "m" ["in" ["o" ["r"]]]