Initializer Methods

  If a class defines a method named init, that method will be invoked
  automatically when new objects of that class are created. The init
  method is referred to as an initializer method. Its purpose is to
  initialize a new object to a valid initial state, usually based on
  arguments supplied to the constructor.

  When writing the code for an initializer, if the class has a superclass,
  it is usually necessary to invoke the superclass' constructor to
  initialize the part of the object defined by the superclass. Class(y)
  provides an automatic mechanism for doing this. The METHOD definition
  command has an extended form which allows a second parameter list to be
  included. Including this second parameter list causes the corresponding
  superclass method to be invoked first, with the specified parameters. The
  syntax for this is as follows:

    METHOD <name>(<params,...>), [<superName>](<superParm,...>)]

  where:

  <name>    is the name of the initializer method.

  <params>  the parameters which the method expects to receive.

  <superName>    is the name of the superclass' initializer. This can and
            should be omitted when the superclass method being invoked has
            the same name as the method being defined. In particular, when
            defining an init method it is not necessary to specify the
            name of the superclass method unless it is other than init.

  <superParm>    are the parameters expected by the superclass' constructor.
            These would typically be a subset of the first parameter list.

  Sometimes a subclass may not need to perform any work to initialize itself
  (perhaps because it has no instance variables). In such cases, it is not
  necessary to define an initializer for that class. If a superclass defines
  an initializer, it will be inherited by the subclass and used during
  initialization.