Documentation of the DATA module
================================

Usage:

       class Sub
       {
               virtual ~Sub();
       };

       class Type
               :  public Sub
       { 
           ... 
       };

       Type *p= Data_Alloc(Type [, args ] );

       if (p == NULL)
       {
             ...
       }

       ... 

       Sub *q= p;

       ...

       Data_Free(q);

   Data_Alloc() creates an object of type Type, constructed with ARGS.
   Return NULL if there is not enough memory.  Objects are freed with
   Data_Free().  p can be NULL when calling Data_Free().  


