CLASS


    CLASS className [INHERITS className]
        [DIM attribute {, attribute}]
        subroutineDefinition
        functionDefintition
    END CLASS

Creates a new user-defined class. Single inheritance is supported. Class attributes are defined in the Dim section.
New instances of a class object are created by calling a constructor method with the same name of the class. For example:


    ' create a Point class
CLASS Point
        DIM x, y
    END CLASS

    ' create a point
    p = Point()
    p.x = 10
    p.y = 20

Objects are automatically destroyed when there are no references to the object. If you want an object to be permanent, create it with the New keyword:

    ' create a Point class
    CLASS Point
        DIM x, y
    END CLASS

    ' create a temporary point and assign some values
    p1 = Point()
    p1.x, p1.y = 10, 20

    ' create a permanent point and assign some values
    p2 = NEW Point()
    p2.x, p2.y = 40, 80

    ' destroy the temporary point
    p1 = NOTHING

    ' This does not destroy the permanent point
    p2 = NOTHING

To destroy an object created with New, use the Dispose command:


    ' Destroy the point
    DISPOSE p2

You can define an initializer for a class by including a NEW method in the class:


' create a Point class
CLASS Point
    DIM x, y

    SUB NEW ( useX, useY )
        x, y = useX, useY
    END SUB
    END CLASS

    ' create a Point
    p1 = Point( 10, 20 )

When an object is destroyed, the FINALIZE routine for it is run:


' create a Point class
CLASS Point
    DIM x, y

    SUB NEW ( useX, useY )
        x, y = useX, useY
        PRINT "Created Point {"; x; ", "; y; ")"
    END SUB

    SUB FINALIZE()
        PRINT "Destroyed the point {"; x; ", "; y; ")"
    END SUB
    END CLASS