anchor.diff:    (let ((etype (element-type c-array)))
       (if (keywordp etype)        
           (mem-ref (pointer c-array) etype
  -                 (calc-gl-index c-array subscripts))
  -        
  +                 (calc-gl-index c-array subscripts))        
           (autowrap:wrap-pointer 
            (let ((ptr (pointer c-array)))
              (inc-pointer ptr (calc-gl-index c-array subscripts)))         
  
positive.code:                        (calc-gl-index c-array subscripts))
                value)
          (let ((obj (autowrap:wrap-pointer 
                      (mem-aptr (pointer c-array) etype
                                (calc-gl-index c-array subscripts))
                      etype)))
            (populate obj value)))))
  
  (defun %aref-c (c-array subscripts)    
    (let ((etype (element-type c-array)))
      (if (keywordp etype)
          (mem-ref (pointer c-array) etype
                   (calc-gl-index c-array subscripts))
          (mem-aptr (pointer c-array) etype
                    (calc-gl-index c-array subscripts)))))
  
  (defun (setf %aref-c) (value c-array subscripts)  
    (let ((etype (element-type c-array)))
  
negative.code:                        (calc-gl-index c-array subscripts))
                value)
          (let ((obj (autowrap:wrap-pointer 
                      (let ((ptr (pointer c-array)))
                        (inc-pointer ptr (calc-gl-index c-array subscripts)))
                      etype)))
            (populate obj value)))))
  
  