[ruby-talk:03537] Re: Ruby classes and inheritance

Hi,

In message "[ruby-talk:03531] Ruby classes and inheritance"
    on 00/06/19, [e-mail] <[e-mail]> writes:

|In C++, there is the concept of an "abstract
|class" that has "pure virtual" functions (methods).
|That is, the methods are specifically and purposely
|NOT defined in the parent, and as a result: 1. They
|MUST be defined in the child, and 2. the class can
|be used only for inheritance, not instantiated.
|
|There does not seem to be any parallel concept in
|Ruby. On the other hand, maybe I don't need it.

Since Ruby is a dynamic typed language, you don't NEED pure virtual
member functions.  But if you want to describe the need for
redefinition of a method implicitly by a program, you can, for
example:

  def must_be_redefined()
     raise NotImplementError, "should be redefined"
  end

							matz.