(goops.info.gz) Class hierarchy and inheritance of slots

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(goops.info.gz) Inheritance

(goops.info.gz) Inheritance

(goops.info.gz) Instance creation and slot access

 
 Class hierarchy and inheritance of slots
 ----------------------------------------
 
 Inheritance is specified upon class definition. As said in the
 introduction, GOOPS supports multiple inheritance.  Here are some class
 definitions:
 
      (define-class A () a)
      (define-class B () b)
      (define-class C () c)
      (define-class D (A B) d a)
      (define-class E (A C) e c)
      (define-class F (D E) f)
 
 `A', `B', `C' have a null list of super classes. In this case, the
 system will replace it by the list which only contains `<object>', the
 root of all the classes defined by `define-class'. `D', `E', `F' use
 multiple inheritance: each class inherits from two previously defined
 classes.  Those class definitions define a hierarchy which is shown in
 Figure 1.  In this figure, the class `<top>' is also shown; this class
 is the super class of all Scheme objects. In particular, `<top>' is the
 super class of all standard Scheme types.
 
      [image src=hierarchy.png text="          <top>
                / \\\\\\_____________________
               /   \\\\___________          \\
              /     \\           \\          \\
          <object>  <pair>  <procedure>  <number>
          /  |  \\                           |
         /   |   \\                          |
        A    B    C                      <complex>
        |\\__/__   |                         |
         \\ /   \\ /                          |
          D     E                         <real>
           \\   /                            |
             F                              |
                                         <integer>
      "]
                            _Fig 1: A class hierarchy_
 
 The set of slots of a given class is calculated by taking the union of
 the slots of all its super class. For instance, each instance of the
 class D, defined before will have three slots (`a', `b' and `d'). The
 slots of a class can be obtained by the `class-slots' primitive.  For
 instance,
 
      (class-slots A) => ((a))
      (class-slots E) => ((a) (e) (c))
      (class-slots F) => ((e) (c) (b) (d) (a) (f))
 
 _Note: _ The order of slots is not significant.
 

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(goops.info.gz) Inheritance

(goops.info.gz) Inheritance

(goops.info.gz) Instance creation and slot access