change_node

# File ext/json/lib/json/editor.rb, line 265
      def change_node(item)
        if current = selection.selected
          parent = current.parent
          old_type, old_content = current.type, current.content
          if ALL_TYPES.include?(old_type)
            @clipboard_data = Editor.model2data(current)
            type, content = ask_for_element(parent, current.type,
              current.content)
            if type
              current.type, current.content = type, content
              current.remove_subtree(model)
              toplevel.display_status("Changed a node in tree.")
              window.change
            end
          else
            toplevel.display_status(
              "Cannot change node of type #{old_type} in tree!")
          end
        end
      end