anchor.diff:  
   (defbinding tree-selection-set-select-function (selection function) nil
     (selection tree-selection)
  -  ((callback %tree-selection-func) pointer)
  +  (%tree-selection-func callback)
     ((register-callback-function function) unsigned-int)
  -  ((callback user-data-destroy-func) pointer))
  +  (user-data-destroy-func callback))
   
   (defbinding tree-selection-get-selected 
       (selection &optional (iter (make-instance 'tree-iter))) boolean
  
positive.code:   (column int)
    (gvalue gvalue))
  
  (defun tree-model-column-value (model iter column)
    (let ((index (column-index model column)))
      (with-gvalue (gvalue)
        (%tree-model-get-value model iter index gvalue))))
  
  
negative.code: ;; and many more functions which we'll add later
  
  
  ;;;; Icon View
  
  #+gtk2.6
  (progn
    (defbinding icon-view-get-path-at-pos () tree-path
      (icon-view icon-view)
      (x int) (y int))
  
    (def-callback-marshal %icon-view-foreach-func 
      (nil icon-view (path (copy-of tree-path))))
  
    (defbinding %icon-view-selected-foreach () tree-path
      (icon-view icon-view)
      ((progn %icon-view-foreach-func) callback)
      (callback-id unsigned-int))
    
    (defun icon-view-foreach (icon-view function)
      (with-callback-function (id function)
        (%icon-view-selected-foreach icon-view id)))
  
    (defbinding icon-view-select-path () nil
      (icon-view icon-view)
      (path tree-path))
  
    (defbinding icon-view-unselect-path () nil
      (icon-view icon-view)
      (path tree-path))
  
    (defbinding icon-view-path-is-selected-p () boolean
      (icon-view icon-view)
      (path tree-path))
  
    (defbinding icon-view-get-selected-items () (glist tree-path)
      (icon-view icon-view))
  
    (defbinding icon-view-select-all () nil
      (icon-view icon-view))
  
    (defbinding icon-view-unselect-all () nil
      (icon-view icon-view))
    
    (defbinding icon-view-item-activated () nil
      (icon-view icon-view)
      (path tree-path))
  
    (defbinding %icon-view-set-text-column (column icon-view) nil
      (icon-view icon-view)
      ((if (integerp column) 
  	 column 
         (column-index (icon-view-model icon-view) column)) int))
  
    (defbinding %icon-view-set-markup-column (column icon-view) nil
      (icon-view icon-view)
      ((if (integerp column) 
  	 column 
         (column-index (icon-view-model icon-view) column)) int))
  
    (defbinding %icon-view-set-pixbuf-column (column icon-view) nil
      (icon-view icon-view)
      ((if (integerp column) 
  	 column 
         (column-index (icon-view-model icon-view) column)) int)))
  