Commands are organized into groups by function. Command lines consist of the name of a command followed by one or more arguments, followed by a semicolon. Arguments are of three kinds: string arguments must be enclosed in double quotes; integer arguments follow ML syntax for integers (negative integers begin with a tilde); the unit argument, written (), is used with those commands that don't actually have an argument. In the noml interface, the unit argument is optional: one can write right; as well as right();.