anchor.diff:              (funcall (callback-error-function callback) c))
             (setf callbacks (delete callback callbacks)))))))
   
  -(defun webkit-web-view-can-execute-editing-command* (web-view command &optional call-back error-call-back)
  +(defun webkit-web-view-can-execute-editing-command (web-view command &optional call-back error-call-back)
     "Execute the editing command in the WEB-VIEW calling CALL-BACK upon completion and ERROR-CALL-BACK on error."
     (incf callback-counter)
     (push (make-callback :id callback-counter :web-view web-view
                          :function call-back
                          :error-function error-call-back)
           callbacks)
  -  (webkit-web-view-can-execute-editing-command
  +  (%webkit-web-view-can-execute-editing-command
      web-view command
      (cffi:null-pointer)
      (cffi:callback can-execute-command-checked)
      (cffi:make-pointer callback-counter)))
  -(export 'webkit-web-view-can-execute-editing-command*)
  +(export 'webkit-web-view-can-execute-editing-command)
   
   (defcfun "webkit_web_view_get_javascript_global_context" js-global-context-ref
     (web-view (g-object webkit-web-view)))
  
positive.code:             (funcall (callback-error-function callback) c))
            (setf callbacks (delete callback callbacks)))))))
  
  (defun webkit-web-view-send-message-to-page* (web-view message &optional call-back error-call-back)
    "Send MESSAGE to the WEB-VIEW corresponding page calling CALL-BACK upon completion and ERROR-CALL-BACK on error."
    (incf callback-counter)
    (push (make-callback :id callback-counter :web-view web-view
                         :function call-back
                         :error-function error-call-back)
          callbacks)
    (webkit-web-view-send-message-to-page
     web-view message
     (cffi:null-pointer)
     (cffi:callback message-replied-to)
     (cffi:make-pointer callback-counter)))
  (export 'webkit-web-view-send-message-to-page*)
  
negative.code:   (js-result webkit-javascript-result))
  (export 'webkit-javascript-result-get-js-value)
  
  (defcfun ("webkit_web_view_send_message_to_page" %webkit-web-view-send-message-to-page) :void
    (view (g-object webkit-web-view))
    (message (g-object webkit-user-message))
    (cancellable :pointer)
    (callback g-async-ready-callback)
    (user-data :pointer))
  
  (defcfun ("webkit_web_view_send_message_to_page_finish" %webkit-web-view-send-message-to-page-finish)
      (g-object webkit-user-message)
  