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    MakeClass -- Create and initialize a boopsi class. (V36)

    iclass = MakeClass( ClassID, SuperClassID, SuperClassPtr,
    D0                  A0       A1            A2
            InstanceSize, Flags )
            D0            D1

    struct IClass *MakeClass( UBYTE *, UBYTE *, struct IClass *,
            UWORD, ULONG );

    For class implementors only.

    This function creates a new public or private boopsi class.
    The superclass should be defined to be another boopsi class:
    all classes are descendants of the class "rootclass".

    Superclasses can be public or private.  You provide a name/ID
    for your class if it is to be a public class (but you must
    have registered your class name and your attribute ID's with
    Commodore before you do this!).  For a public class, you would
    also call AddClass() to make it available after you have
    finished your initialization.

    Returns pointer to an IClass data structure for your
    class.  You then initialize the Hook cl_Dispatcher for
    your class methods code.  You can also set up special data
    shared by all objects in your class, and point cl_UserData at it.
    The last step for public classes is to call AddClass().

    You dispose of a class created by this function by calling

    ClassID = NULL for private classes, the name/ID string for public
    SuperClassID = name/ID of your new class's superclass.  NULL if
            superclass is a private class
    SuperClassPtr = pointer to private superclass.  Only used if
            SuperClassID is NULL.  You are required never to provide
            a NULL superclass.
    InstanceSize = the size of the instance data that your class's
            objects will require, beyond that data defined for
            your superclass's objects.
    Flags = for future enhancement, including possible additional
            parameters.  Provide zero for now.

    Pointer to the resulting class, or NULL if not possible:
    - no memory for class data structure
    - public superclass not found
    - public class of same name/ID as this one already exists


    Creating a private subclass of a public class:

/* per-object instance data defined by my class     */
struct MyInstanceData {
    ULONG   mid_SomeData;

/* some useful table I'll share use for all objects */
UWORD myTable[] = {
    5, 4, 3, 2, 1, 0

struct IClass       *
    ULONG __saveds  myDispatcher();
    ULONG   hookEntry();    /* asm-to-C interface glue       */
    struct IClass   *cl;
    struct IClass   *MakeClass();

    if ( cl =  MakeClass( NULL,
                SUPERCLASSID, NULL,  /* superclass is public */
                sizeof (struct MyInstanceData),
                0 ))
        /* initialize the cl_Dispatcher Hook       */
        cl->cl_Dispatcher.h_Entry = hookEntry;
        cl->cl_Dispatcher.h_SubEntry = myDispatcher;
        cl->cl_Dispatcher.h_Data = (VOID *) 0xFACE; /* unused */

        cl-cl_UserData = (ULONG) myTable;
    return ( cl );

    The typedef 'Class' isn't consistently used.  Class pointers
    used blindly should be APTR, or struct IClass for class implementors.

    FreeClass(), AddClass(), RemoveClass(), NewObject(),
    Document "Basic Object-Oriented Programming System for Intuition"
    and the "boopsi Class Reference" document.

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