def bit_file

      #Determine ISE's working directory.
      working_directory = get_property(WorkingDirectoryProperty)

      #Find an absolute path at which the most recently generated bit file should reside.
      name = get_property(OutputNameProperty)
      name = File.expand_path("#{working_directory}/#{name}.bit", @base_path)

      #If it exists, return it.
      File::exists?(name) ? name : nil

    end
def bit_file

      #Determine ISE's working directory.
      working_directory = get_property(WorkingDirectoryProperty)

      #Find an absolute path at which the most recently generated bit file should reside.
      name = get_property(OutputNameProperty)
      name = File.expand_path("#{working_directory}/#{name}.bit", @base_path)

      #If it exists, return it.
      File::exists?(name) ? name : nil

    end
Returns the best-guess path to the most recently generated bit file,
 or nil if we weren't able to find one.