anchor.diff:  ;; TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
   ;; SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   
  -;; $Id: gtktree.lisp,v 1.17 2006-02-28 16:33:39 espen Exp $
  +;; $Id: gtktree.lisp,v 1.18 2006-03-03 19:00:12 espen Exp $
   
   
   (in-package "GTK")
  
positive.code: 			 (funcall setter value iter))
  		 row setters)))))))
  
  (defun (setf tree-model-value) (value model row column)
    (let ((iter (etypecase row
  		(tree-iter row)
  		(tree-path (multiple-value-bind (valid iter)
  
negative.code:   (column int)
    (gvalue gvalue))
  
  (defgeneric tree-model-value (model row column))
  
  (defmethod tree-model-value ((model tree-model) row column)
    (let ((index (column-index model column))
  	(iter (etypecase row
  		(tree-iter row)
  